CULTURAL RESOURCE MANAGEMENT
CRM VOLUME 22 NO. 6 1999
Conserving Earthen Architecture
Conservando la Arquitectura de Tierra
U.S. DEPARTMENT OF THE INTERIOR National Park Service Cultural Resources PUBLISHED BY THE ^SS.~%±£±r%l.—i VOLUME 22 NO. 6 1999 NATIONAL PARK SERVICE Information for parks, federal agencies, OOniCntS ISSN 1068-4999 Indian tribes, states, local governments, and the private sector that promotes and Conserving Earthen Architecture maintains high standards for preserving and managing cultural resources Conservando la Arquitectura PUBLICADO POR NATIONAL PARK SERVICE Información para los parques, enti de Tierra dades federales, tribus indígenas, estados, goviernos locales, y el sector A Rich Building Tradition/ Una Rica Tradición de Construcción 3 privado, buscando promover y man Jake Barrow and Michael RomeroTaylor tener los más altos estándares para la Adobe Today 5 preservación y la gestión de los recur sos culturales. Paul G. McHenry Training in the Conservation of Earthen Architectural Heritage/Formación en DIRECTOR el Campo de la Conservación del Patrimonio Arquitectónico de Tierra 7 Robert Stanton Marina Trappeniers ASSOCIATE DIRECTOR Building Institutional Alliances—Project Terra/Establecimiento de Alianzas CULTURAL RESOURCE STEWARDSHIP AND PARTNERSHIPS Institucionales—Proyecto Terra 14 Katherine H. Stevenson Erica Avrami
EDITOR Earthen Architecture Traditions in New Mexico/ Tradiciones de Arquitectura de Tierra Ronald M. Greenberg en Nuevo México 21 Michael Romero Taylor ASSOCIATE EDITOR Janice C. McCoy Earthen Architecture and Incentives at Acoma Pueblo 27 Ed Crocker GUEST EDITORS Jake Barrow Earthen Architecture in the Northern United States—European Traditions in Michael RomeroTaylor Earthen Construction 30 Richard Pieper ASSISTANT Denise M. Mayo California's Historic Earthen Architecture/Arquitectura Histórica de Tierra en California 34 An electronic version of this Edna E. Kimbro issue of CRM can be accessed Earthquakes and Adobes—Effects and Systems for Intervention/ Terremotos through the CRM homepage at y Adobes—Efectos y Sistemas de Intervención 39
2 CRM No 6—1999 Jake Barrow and Michael Romero Taylor A Rich Building Tradition Una Rica Tradición de Construcción
his issue of CRM is dedicated to sta publicación de CRM está the conservation and preserva dedicada a la conservación y tion of earthen architecture and preservación de la arquitectura its building traditions. It is a de tierra y de sus tradiciones bilinguaTl issue, with several entries translated into constructivasE. Es una publicación bilingüe que Spanish.The Southwest of the United States contiene diversos artículos traducidos al shares a rich traditional commonality with Latin español. El sudoeste de los Estados Unidos y America. International training and meetings in Latinoamérica comparten una gran riqueza de Peru and Mexico occurring in 1999 will offer tradiciones. Durante 1999 se llevarán a cabo en challenging opportunities for professionals to Perú y México encuentros y cursos de capac share and engage on many of the themes set itación de carácter internacional, los cuales forth. ofrecen grandes oportunidades y desafíos para One of the main objectives of this issue is to que los profesionales puedan compartir e José Padilla and make the reader aware of the fact that somewhere involucrase en los temas propuestos. Napoleon Duran between one third and one half of the world's Esta publicación tiene entre sus princi repair windows at population lives in some type earthen structure. pales objetivos demostrar al lector que la mitad Ft. Union National Here in the United States there exists a tremen de la población mundial vive en algún tipo de Monument. dous inventory of historic earthen buildings— estructura de tierra y que aquí, en los Estados José Padilla y not only in the Southwest, but throughout the Unidos contamos con un enorme legado de Napoleon Duran country. edificios históricos construidos en tierra, no reparan ven solamente en el Sudoeste, sino en todo el país. tanas en el The articles reflect a wide spectrum of pre Monumento historic, historic, and contemporary uses of earth Los artículos muestran el amplio espectro National de Ft as a building material, and address the preserva de usos prehistóricos, históricos y contemporá Union. tion of these structures. The reader will learn of neos de la tierra como material de construc global initiatives in ción, abordando el tema de la preservación de preserving and per estas estructuras. Se presentan aquí al lector las petuating this venera iniciativas internacionales destinadas a preservar ble building material y perpetuar este venerable material de construc and how living in ción, para lograr comprender que la tierra es el earth is the preferred medio arquitectónico favorito en diversas architecture in many regiones del mundo, porque es sustentable y parts of the world fácil de trabajar y por sus características térmi because it is sustain cas son construcciones que permiten vivir able and easy to work cómodamente. Se sorprenderán algunos lec with, and due to its tores al saber que en Nueva York, un estado thermal character- reconocido por su duro clima, aún existen isitcs, comfortable to estructuras de tierra en uso y que en un período live in. It may surprise de 7.000 años en toda la región del Medio some to know there Oeste y Este de los Estados Unidos los indíge are many historic nas americanos construían obras monumentales actively-used earthen en tierra. A otros lectores les sorprenderá enter structures in New arse de las iniciativas de cooperación interna York State. Also, cional para preservar la arquitectura de tierra throughout the que se están llevando a cabo en la frontera entre
3 Wilfred Valencia Americas Midwest and los Estados Unidos y turning adobes East there was a 7,000- at Ft. Union México, o saber que National year period during muchos de los fuertes Monument. which Native militares históricos en Wilfred Americans were build el Oeste estaban con Valencia ing monumental earth struidos con tierra, rodando works and that many of adobes en el con sus frágiles restos Monumento the historic military iluminando la época National de Ft. forts in the West were de la expansión al Union. built out of earth, their Oeste en el siglo XIX. fragile remains illumi Tenemos claro que el nating the times of conjunto de artículos 19th-century westward reunidos aquí es un expansion. Currently there are international modesto reflejo de la actividad de la arquitectura cooperative initiatives to preserve earthen archi de tierra. Esperamos con esta publicación estimu tecture along the US/Mexico Borderlands. We lar en otros el estudio de este tema, para así con recognize that these articles reflect only a small tinuar enriqueciendo los conocimientos con que part of earthen architectural activity and hope contamos hasta la fecha. that this issue will stimulate others to consider A diferencia de las construcciones de piedra, the topic and continue to enlarge the body of las estructuras de tierra retornan al suelo cuando knowledge. se las abandona. Los vestigios arqueológicos de Unlike stone, brick, or timber buildings, este medio de construcción son sutiles y en earthen structures melt back into the earth when muchos casos han desaparecido por completo. left abandoned. The archeological vestiges of this Allí donde existen construcciones de tierra prote building medium are subtle and many times have gidas de la humedad y de los elementos, se puede disappeared completely. Where earthen buildings reconocer una enorme variedad de estilos y méto have been protected from moisture and the ele dos de construcción y trabajo artesanal. ments, there exists a tremendous variety of build Esperamos que disfruten con estos artículos y ing styles, methods and craftsmanship. We hope aprendan algo de las ricas tradiciones de con that you enjoy these articles and learn about the strucción con tierra en los Estados Unidos. rich traditions of building with earth in the United States. Jake Barrow es Especialista Mayor de Exhibiciones en El Programa de Conservación de Proyectos Arquitectónicos, Jake Barrow is Senior Exhibit Specialist in the Región Intra-montoñosa, Oficina de Apoyo de Santa Fe, Architectural Conservation Projects Program, National Park Service. Interrnountain Region, Santa Fe Support Office, National Park Service. Michael Romero Taylor es Subdirector de New Mexico State Monuments, unidad del Museum of New Mexico de Michael Romero Taylor is the Deputy Director, New Santa Fe, y es miembro de US/ICOMOS. Mexico State Monuments, a unit of the Museum of New Mexico in Santa Fe, and he is a member ofUS/ICOMOS. Jake Barrow y Michael Romero Taylor son los editores invitados para ésta entrega de CRM. Jake Barrow and Michael Romero Taylor are guest editors of this issue o/CRM. Fotos cortesía de Robert Hartzler. Photos courtesy Robert Hartzler. Agradecimientos Acknowledgments JN uestros agradecimientos al Getty Conservation We want to thank the Getty Conservation Institute por el apoyo brindado a este esfuerzo a través Institute who supported this effort through Project del Proyecto Terra, un proyecto conjunto del Getty Terra, a collaboration of the Getty Conservation Conservation Institute, el Centro Internacional para el Institute, the International Center for the Study of the Estudio de la Conservación y Restauración del Preservation and Restoration of Cultural Property Patrimonio Cultural (ICCROM), y el Centro (ICCROM), and the International Center for Earth Internacional de Construcción de Tierra de la Escuela de Construction, School of Architecture of Grenoble, Arquitectura de Grenoble, Francia (CRATerre-EAG). France (CRATerre-EAG). We also would like to thank Vayan también nuestros agradecimientos a Jennifer Jenifer Blakemore, Jane Harvey, Anna Zagorski, and Blakemore, Jane Harvey, Anna Zagorski, y Inés Cox por Inés Cox for editing and translating assistance. su apoyo editorial y traducción.
4 CRM No 6—1999 Paul G. McHenry Adobe Today
dobe is the oldest and most widely available building material used by man. A surprising ¿.as Tampas fact abouAt adobe is that nearly half the Church, an people of the world today live in adobe example of adobe architec or earthwall houses. The second sur ture. prise is that adobe is much more durable than one might think. Popular perception is that adobe is used only in a desert or arid lands climate. Nothing could be Adobe in the United States further from the truth, as it is found in every cli Building with earth was a common occur mate zone, with the exception of the Arctic and rence in early America, from the eastern seaboard Antarctic zones. Even in the Arctic, igloos are to the Rocky Mountain west and to the Pacific built with the same principles as adobe domes, Ocean. Better building materials were not but with snow blocks instead of dried earth unknown, but earth often was used when other bricks. (better) materials were unavailable or too expen There are several types of earthwall build sive. Rammed earth buildings are still found in ings. The two major ones are adobe (sun-dried North and South Carolina, Virginia, and mud brick laid up with earth mortar and dried Washington, DC. At a recent international con by the sun), and rammed earth, or pisé, (earth ference on adobe preservation, an architect from compacted in forms to make the wall). Both use New York identified more than 25 adobe homes the same material, but rammed earth is used in in the State of New York. (See Pieper article, p. 30.) humid climate areas where rain and dampness There are many materials that are stronger, would slow or prevent sun drying of the bricks. more long lasting, and better than adobe, but the Both systems are widely used, with the type of advantages and utility of adobe are repeatedly building system chosen dependent on the local rediscovered in our history alone. Countless com climate and the tradition of the builder. There are munities, particularly in the western United also two other common types of earthwall build States, needed buildings for homes, commercial ings. One is called jacal, or Bajareque, and it uses enterprises, and public works, but they were a wood/thatch armature to support the mud; the located far from the supplies of more conven other is a "puddled" (wet-placed mud) form. tional building materials. Furthermore, econom Worldwide Tradition ics was an additional driving factor. There are in The basics of earthwall construction are New Mexico countless churches, homes, and similar worldwide, but with some notable excep commercial buildings. Sometimes the facade of a tions. In the Middle East, where trees for struc merchant's store was made of fired brick while tural members are very scarce or nonexistent, a the rest of the walls were made of adobe. A system of arches and domes was developed per Department of Energy study in the State of haps as early as 7000 B.C. The ingenuity and Colorado uncovered many adobe buildings of masonry skills are truly incredible. Consider the great age. They were built in various styles, and imagination it took to figure out a way to build a often the residents were not aware that these were roof structure with a span of 50' or more, using earth buildings. only pieces that are less than 10" in length. This In 1941, a large elementary school was was done, and the technology transferred from needed in the small town of Anthony, New the Middle East to the shores of the Mexico. The city did not have money to build it, Mediterranean and on to Italy and Europe. so public-spirited citizens got together, made
CRM No 6—1999 5 bricks from the local where he was accused of trying to return housing soil, and employed to the Middle Ages. townspeople in need Public Image of jobs to build their Where this material was used only by school. It is in sound "poor" people, it is now a premium material. shape today. The Look at Santa Fe, New Mexico! Poor people, Works Progress indeed, live here. And, high-end homes made of Administration adobe are very popular in Santa Fe, often favored (WPA) made wide by people from other areas where high-priced use of adobe and housing is common. rammed earth during In 1981, the Bureau of Indian Affairs (BIA) the drought and wanted to build adobe housing on several Native Great Depression of American reservations, but rejected the idea as the 1930s. Farmers "too expensive." Unfortunately, the attitude of were relocated to the BIA reflects attitudes by the architectural Bosque Farms, New community as well, which values what is new and Mexico, where the ignores many benefits from the past. government provided The Future plats of irrigated land Mankind has an extensive history of repeat and arranged for the edly abusing and exhausting natural resources. design and construc Energy, natural resources, and ecology will suffer. tion of more than 40 It cost surprisingly large amounts of energy to small homes. The manufacture modern building materials. For government super example, it takes one gallon of gasoline to make Dervish vised the construction of the homes, which were eight common bricks. In the past, when the Mosque, leased to displaced persons who were to become effects of manufacturing building materials Mahan, Iran, covered with future owners. There are 42 of these homes in use reached catastrophic proportions, earth building tile. today. Many of the designs have been modern has come to the rescue. ized to meet today's standards and expanded to In most industrial nations the art of build provide the additional space. ing with earth is a lost one. We must create a Lost Technology corps of skilled professionals who are ready to The skills for building with earth are quite train others and provide answers to questions simple and were well known to almost everyone with regard to earthen construction. The main until World War II. However, after the war, the villain of this situation is ignorance. It starts with new "modern" materials became the first choice the basic tenets of architecture and architectural because they were, in some ways, better than education, and it ends with the creation of unre adobe, and they were affordable. In addition, the alistic buildings and zoning regulations. These building industry was under tremendous pressure regulations are made, of course, with the best to keep up with explosive growth. The industry's intentions, but frequently fall short of meeting rapid growth and the influx of new materials practical needs. resulted in a whole generation of architects, engi In 1997, the Earth Architecture Center neers, and building professionals who in their International was created to collect and dissemi entire careers never once experienced working nate accurate technical information on earthen with adobe. In this gap of 40 to 50 years, adobe building. In 1998, it was transformed into the took on an image of poverty, a perception that Earth Building Foundation. For further informa persists today. The technology was almost lost, tion on this organization, please visit our web site except in primitive economies and among a few
6 CRM No 6—1999 Marina Trappeniers Training in the Conservation of Earthen Architectural Heritage Formación en el Campo de la Conservación del Patrimonio Arquitectónico de Tierra
he first international expressions niciando la década del 70 se enun regarding the need to preserve the ciaron las primeras expresiones a world's earthen architectural her nivel internacional relacionadas con itage were voiced in the early 1970s. la necesidad de conservar el patrimo TThe international recommendations, nio arquitectónicI o de tierra del mundo. approved from 1972 to 1987 in different meetings Las recomendaciones internacionales held on this subject and supported by the national aprobadas entre 1972 y 1987 en distintas con International Council of Monuments and Sites ferencias organizadas para tratar el tema, con el (ICOMOS) committees, reflect the thoughts and apoyo del International Council of Monument concerns at various times regarding the need for and Sites (Comités de ICOMOS) son un specific activities in the field. Yazd, Iran, (1972)1 reflejo del pensamiento e intereses expresados and Yazd, Iran, (1976)2 may be seen as the first en distintas ocasiones sobre la necesidad de systematic attempts to characterize earthen archi realizar acciones específicas en este campo. tectural heritage and to outline preliminary rec Yazd, Irán, (1972)1 y Yazd, Irán, (1976)2 ommendations for their preservation. The interim pueden considerarse como los primeros inten meeting in Santa Fe, New Mexico,^ clearly identi tos sistemáticos de caracterizar el patrimonio fied the urgent need to conduct research on spe arquitectónico de tierra y esbozar algunas cific areas. An attempt to follow up the Santa Fe recomendaciones preliminares para su conser recommendations was made by researchers of the vación. En la reunión de Santa Fe, Nuevo Institute for Applied Technology and the Center México, se identificó claramente la necesidad for Building Technology/National Engineering urgente de realizar investigaciones en áreas Laboratory (National Bureau of Standards/USA). específicas. Los investigadores del Institute of Although a subsequent meeting in Ankara, Turkey, Applied Technology y del Center for Building (1980)4 did not record further development of the Technology/National Engineering Laboratory previous recommendations, this forum encour (National Bureau of Standards) de los Estados aged a broader view of the field by introducing the intentaron hacer un seguimiento de las expression "earthen architecture" and it fine-tuned recomendaciones de Santa Fe. Si bien en la all previous recommendations. In Lima, Peru, reunión siguiente realizada en Ankara, Turquía, (1983)' specific concerns about the development (1980)4 no se registraron mayores avances en of a network for this field were expressed and las recomendaciones anteriores, el foro amplió intensive training in established centers was rec la perspectiva del campo al introducir la expre ommended. sión "arquitectura de tierra", ajustando todas las It was finally in Rome, Italy, (1987)6 that recomendaciones anteriores. En Lima, Perú, commitments were made by the International (1983)-* se expresaron intereses más específicos Center for the Study of the Preservation and centrados en el desarrollo de una red para esta Restoration of Cultural Property (ICCROM), actividad, recomendando realizar una forma CRATerre, and the School of Architecture of ción intensiva en centros ya establecidos.
CRM No 6—1999 7 Grenoble to carry out training activities with the Fue finalmente en Roma, Italia, (1987) formulation of the Gaia Project, a comprehensive donde se llegó a un compromiso del Centro plan of action in the field of the preservation of Internacional para el Estudio de la Conservación earthen architectural heritage. The Gaia Project y Restauración del Patrimonio Cultural was set up within the framework of a formal (ICCROM), de CRATerre y la Escuela de agreement to ensure continuous activity in train Arquitectura de Grenoble, para realizar activi ing, research, documentation, and technical coop dades de formación a través del Proyecto Gaia, eration. The agreement grew out of the critical un plan global de acción en el campo de la con evaluation of the implementation of international servación del patrimonio arquitectónico de recommendations, and it is the result of these tierra. El Proyecto Gaia tomó forma en el marco three signatory institutions' five years of coopera de un acuerdo formal que garantiza una activi tion, which included the gradual exchange of dad permanente de formación, investigación, training experience, the common organization of documentación y cooperación técnica. El scientific events, the development of publications, acuerdo surgió de una evaluación crítica de la and many other activities. puesta en práctica de las recomendaciones inter International Activities nacionales y ha sido posible gracias a los cinco The Gaia Project has given a fresh boost to años de cooperación entre las tres instituciones the training of conservation professionals and to signatarias, que incluyeron el intercambio gradual the development of their own international net de experiencias en formación, la organización con work through the four Preservación Architectura junta de eventos científicos, el desarrollo de publi de Tierra (PAT) courses that were organized at the caciones y muchas actividades más. headquarters of CRATerre in the School of Actividades Internacionales Architecture of Grenoble (a pilot course in 1989, El Proyecto Gaia ha dado un nuevo followed by three international courses in 1990, impulso a la formación de profesionales de la 1992, and 1994). In addition to CRATerre-Ecole conservación y al desarrollo de su propia red dArchitecture de Grenoble (EAG) and internacional, a través de los cuatro cursos inter ICCROM's own contributions, these courses were nacionales "Preservación Arquitectura de Tierra" granted financial support from the Council of (PAT) organizados en la sede de CRATerre en la Europe, the European Union, the Aga Khan Escuela de Arquitectura de Grenoble (un curso Award for Architecture, and the Rhóne-Alpes piloto en 1989 al que siguieron tres cursos inter Region. Twenty instructors, mostly from the nacionales en 1990, 1992 y 1994). Además de Americas and Europe, contributed to the develop los aportes propios de CRATerre-Ecole ment of the courses' contents, which addressed d'Architec-ture de Grenoble (EAG) y del the general principles of preservation practice; sci ICCROM, estos cursos obtuvieron apoyo entific considerations on the earthen material and financiero del Consejo de Europa, de la Unión its relevant construction techniques, documenta Europea, del Premio Aga Khan de Arquitectura tion, survey, and inspection; the preservation of y de la región de Rhóne-Alpes. Veinte instruc archeological sites; and the rehabilitation of the tores provenientes en gran parte de las Americas earthen architectural heritage. y Europa contribuyeron al desarrollo de con The courses established a network of some tenidos de los cursos que abordaron los princip 120 professionals from Europe, the Americas, ios generales de la práctica de conservación; Africa, and Asia. Two other conferences, Adobe 90 aspectos científicos del material terreo y técnicas (Las Cruces, New Mexico, 1990)7 and Terra 93 de construcción, documentación, estudio e (Silves, Portugal, 1993),8 provided this network inspección correspondientes; la preservación de with a forum for the exchange of ideas, methods, sitios arqueológicos; y la rehabilitación del patri techniques, and research findings. monio arquitectónico de tierra. These events have shown, however, that the Gracias al curso se estableció una red de demand for training is still growing thus empha 120 profesionales de Europa, América, África y sizing the need for additional training programs in Asia. Dos nuevas conferencias, "Adobe 90" (Las Cruces, Nuevo México, 1990)7 y "Terra 93" the field, both on a regional and a national scale. (Silves, Portugal, 1993),8 permitieron disponer de un foro para el intercambio de ideas, metodologías, técnicas y resultados de investiga ciones. Sn embargo ha quedado demostrado en
8 CRM No 6—1999 Regional Activities estos eventos que existe una demanda creciente Since its creation in 1989, the Gaia Project por formación que enfatiza la necesidad de orga has stressed the importance of organizing regional nizar más programas de formación en este activities in an institutional framework so as to campo, tanto a escala regional como nacional. guarantee the activities' continuation. Actividades Regionales In 1996, the Gaia Project and the Instituto Desde su creación en 1989 el Proyecto Nacional de Cultura de Perú organized, in collab Gaia ha insistido en la importancia de organizar oration with the Getty Conservation Institute actividades regionales en un marco institucional (GCI) and with the sponsorship of the European que asegure la continuidad de las actividades. Union and the World Heritage Fund of the En 1996, el Proyecto Gaia y el Instituto United Nations Educational, Scientific, and Nacional de Cultura del Perú organizaron en Cultural Organization (UNESCO), the first colaboración con el Getty Conservation Curso Panamericano sobre la Conservación y el Institute (GCI) y con el patrocinio de la Unión Manejo del Patrimonio Arquitectónico Historico- Europea y el Fondo Mundial del Patrimonio de Arqueologico de Tierra. Classes were held at the la UNESCO, el primer Curso Panamericano museum of the archeological site of Chan Chan, a sobre la Conservación y el Manejo del 14-km2 earthen city in northern Peru. Twenty- Patrimonio Arquitectónico Histórico- four architects, archeologists, and conservators Arqueológico de Tierra. Las clases se desarrol from 13 countries participated in the intensive laron en el Museo del sitio arqueológico de five-week course. They were selected from a Chan-Chan, zona arqueológica construida de highly qualified pool of nearly 175 applicants tierra de 14 km2 situada en la costa norte del from 20 countries. Twenty instructors from the Perú. Veinticuatro arquitectos, arqueólogos y Americas and Europe combined lectures, demon conservadores de trece países participaron en el strations, and exercises to convey a dense curricu curso intensivo de cinco semanas. Fueron elegi lum of theoretical and practical issues. Due to the dos de una selección previa de casi 175 can high seismic risk in many areas of Latin America, didatos altamente calificados provenientes de seismic mitigation was emphasized throughout veinte países. Veinte instructores americanos y the course. Also, because of the wealth of poly europeos combinaron charlas, demostraciones y chrome murals and reliefs in the region, a signifi ejercicios centrados en la transmisión de un cur riculum de aspectos teóricos y prácticos. Debido cant portion of the curriculum focused on deco al alto riesgo sísmico de muchas regiones de rated surfaces on earthen supports. One of the América Latina, durante todo el curso se puso main concerns was the site's size, a feature that has énfasis en aspectos de mitigación de terremotos. led to the definition of a particularly complex Asimismo, dada la gran riqueza de murales y conservation management plan. relieves polícromos en la región, una parte Thus the first regional experience of the importante del programa trató aspectos de Gaia Project—the outcome of a long and complex superficies decoradas sobre soportes de tierra. process—began to set up a pedagogic program Una de las principales condicionantes de tal with the appropriate didactic and pedagogic mate zona es la escala del sitio, lo que llevó a definir rials. un plan de manejo de la conservación suma Another regional activity of the Gaia Project mente complejo. concerns the development of a pedagogic program De este modo, la primera experiencia for the Escola Nacional de Artes e Oficios regional del Proyecto Gaia, resultado de un pro Tradicionais (ENAOTS) in Serpa, Portugal. This ceso largo y complejo, dio inicio a la conforma school for artisans and entrepreneurs was estab ción de un programa pedagógico con los materi lished by the Director General de Edificios y ales didácticos y pedagógicos correspondientes. Monumentos Nacional (DGEMN) of Portugal. Otra actividad regional del Proyecto Gaia Field Activities es el desarrollo de un programa pedagógico para At the same time, a series of short courses la Escola Nacional de Artes e Oficios and workshops were arranged by some partici Tradicionais (ENAOTS) en Serpa, Portugal. pants of the international PAT courses. These Esta escuela para artesanos y empresarios fue practical training sessions are for the most part creada por la Dirección General de Edificios y organized on a local level. Cornerstones Monumentos Nacionales de Portugal. Community Partnerships (Santa Fe, New Mexico)
CRM No 6—1999 9 can be cited as a most successful partnership in Actividades in-situ which this organization and communities have En paralelo algunos participantes de los developed programs that teach young people tra cursos internacionales PAT organizaron una ditional building skills. serie de cursos cortos y talleres. En su mayoría The Gaia Project has also organized various estas sesiones de formación práctica se han orga training programs in the field, mainly in Africa nizado a nivel local. Cornerstones Community (Mali, Benin, Nigeria, Ghana, to name a few Partnerships de Santa Fe, Nuevo México, puede countries). Most training programs are organized citarse como una asociación muy exitosa en la within the institutional framework of a larger que esta organización y las comunidades desar preservation project, and they are often set up by rollan programas para enseñar a los jóvenes las a local individual who has received instruction in técnicas de construcción tradicional. one of the PAT courses. As these programs serve El Proyecto Gaia ha organizado también specific locales, they do not meet the regional varios programas de capacitación a nivel local, demand for training. principalmente en el África (en Mali, Benin, The Current Situation Nigeria, Ghana, para nombrar sólo algunos The dynamic process activated by the PAT países). La mayoría de los programas de capac courses as well as by other activities of the Gaia itación se organizan dentro del marco institu Project (research, documentation, technical assis cional de un proyecto de conservación mayor y tance and dissemination) has had positive effects normalmente son montados por una persona on different levels: del lugar que recibió instrucción en alguno de • Through the support of activities initiated by los cursos PAT Por tratarse de programas que international and national organizations con sirven a necesidades locales específicas, no centrating on better coordination and a wider cubren la demanda regional de formación. dissemination of information resulting from the La situación actual experience of a network of identified partici El proceso activado por los cursos PAT, pants, the implementation of the mandates and como por otras actividades del Proyecto Gaia the role of the Gaia Project have enabled the (investigación, documentación, asistencia téc development of a greater consciousness not nica y divulgación) ha tenido efectos positivos only of the value of our earthen architectural en distintos niveles. heritage but also of the need to define and • Gracias al apoyo de las actividades iniciadas establish integrated policies and strategies for por las organizaciones internacionales y their conservation, their management, and their nacionales, a una mejor coordinación y una mise en valeur. divulgación más amplia de la información • The integrated approach to the earthen archi obtenida de la experiencia de una red de par tectural heritage, which takes into account cul ticipantes conocidos, más la implementación ture and development, has been more precisely de mandatos y el papel del Proyecto Gaia, ha articulated. This more definitive approach fur sido posible crear mayor conciencia no sólo ther integrates the conservation of historical del valor de nuestro patrimonio arquitec and vernacular heritage and the application of tónico de tierra, sino también de la necesidad the potential of constructive cultures in the de definir y establecer políticas y estrategias field of housing and public buildings in both integradas para su conservación, manejo y industrialized and developing countries. valoración. • The development and expansion of different • Se ha logrado articular con mayor precisión national and regional networks of those un enfoque integrado del patrimonio arqui working in the field of the conservation of tectónico de tierra que toma en cuenta la cul earthen architecture is remarkable. tura y el desarrollo. Este enfoque más claro Although much has been done in the train permite integrar mejor la conservación del ing arena, we still observe two main problems: patrimonio histórico y regional con la apli The number of specialists trained through the cación del potencial de las culturas constructi PAT courses and by the different local or regional vas en el área de la vivienda y obras públicas, initiatives is slight given the demand for qualified ya sea en países industrializado como en professionals throughout the world, and the desarrollo.
lü CRMN06—1999 knowledge stemming from operational programs • El desarrollo y expansión de las diferentes and resulting from research programs has been redes nacionales y regionales de personas que transmitted through intermittent rather than on trabajan en el campo de la conservación de la going activities. arquitectura de tierra es impresionante. The Gaia Project has thus reformulated its Aunque se ha avanzado mucho en forma mandates with regards to training and is moving ción, notamos que persisten dos grandes prob into a new phase of dissemination of information lemas: el número de especialistas formados a and expertise. In 1998, the Getty Conservation través de los cursos PAT y por las diversas ini Institute (GCI), ICROM, CRATerre, and the ciativas locales o regionales es bastante School of Architecture of Grenoble agreed to reducido, considerando la demanda por profe establish within a new framework a collaborative sionales calificados en todo el mundo; el program, Project Terra, for the study and conser segundo, que los conocimientos surgidos de vation of earthen architecture. Previous institu programas operativos y de investigación se han tional activities developed through the Gaia transmitido en actividades esporádicas y no per Project, as well as the GCI's past activities in the manentes. field, will contribute to Project Terra. Ante esta situación el Proyecto Gaia ha Project Terra reformulado sus mandatos respecto a la forma The first regional course, organized in Peru ción y está pasando a una nueva etapa de divul in 1996, can be considered a turning point for gación de la información y aprendizajes. En the Gaia Project and Project Terra. The course 1998, el Getty Conservation Institute (GCI), el offered specialized training in the conservation ICCROM, CRATerre y la Escuela de and management of earthen heritage in a specific Arquitectura de Grenoble acordaron establecer context, and it did this in collaboration with a un nuevo marco para inscribir un programa de local institutional partner. In this way, the course colaboración, el Proyecto Terra, orientado al is a prototype of the educational activities of estudio y conservación de la arquitectura de Project Terra, whose main objective is to ensure tierra. Las actividades previas desarrolladas en el that the conservation of earthen heritage is firmly marco del Proyecto Gaia y las actividades ante established in formal education curricula through riores del GCI en este campo se inscribirán • the development of faculty, dentro del Proyecto Terra. • the introduction of the field and its concepts Proyecto Terra to university programs and other formal edu El primer curso regional organizado en el cation programs that exist or that are under Perú en 1996 puede considerarse como un development, momento decisivo para el Proyecto Gaia y el • the preparation of didactic materials for teach Proyecto Terra. El curso ofreció una formación ing situations, and especializada en la conservación y manejo del • the refinement of curriculum content through patrimonio de tierra dentro de un contexto methodology development. específico y lo hizo en colaboración con un aso ciado institucional local. Así, este curso es un The experience of PAT96 will be consoli prototipo de las actividades educativas del dated through the organization of PAT99, the Proyecto Terra, cuyo objetivo principal es ase second regional course that is currently being gurar que el tema de la conservación del patri developed by the initiators of Project Terra in col monio de tierra logre insertarse con fuerza en el laboration with the local partners. PAT99 will curriculum de la educación formal mediante: involve the participation of local and regional • el desarrollo de un cuerpo docente; universities in the different stages of the develop • la introducción del campo y sus conceptos ment and implementation process of an appro dentro de programas universitarios y otros priate curriculum, so as to prepare them to programas de educación formal ya existentes become training centers in the field of the conser o en desarrollo; vation and management of earthen architecture • preparación de materiales didácticos para for the Latin American region. situaciones de enseñanza, y Similar initiatives were set up for the con •el refinamiento del contenido curricular medi servation of immovable cultural heritage in Sub- ante el desarrollo metodológico Saharan Africa by the Africa 2009 program, an La experiencia de PAT96 se consolidará a effort that is based on an agreement between the través de la organización de PAT 99, el segundo
CRM No 6—1999 11 World Heritage Centre of UNESCO, ICCROM, curso regional que están poniendo en marcha and CRATerre-EAG. In cooperation with various hoy los iniciadores del Proyecto Terra, junto con African institutions, this program is developing a sus asociados locales. PAT99 implicará la partici comprehensive method for training a broad spec pación de universidades locales y regionales en las trum of people involved in the use and upkeep of distintas etapas del proceso de desarrollo e imple- this heritage in order to improve the conditions for mentación de un curriculum apropiado que las its conservation. prepare para transformarse en centros de forma The UNESCO Chair on ción en el campo de la conservación y manejo de Earthen Architecture la arquitectura de tierra para la región latino Given its activities and its goal to incorporate americana. into the university curriculum the conservation of Se organizaron iniciativas similares para la earthen architecture, Project Terra meets the main conservación del patrimonio cultural inmueble objective of the UNESCO Chair on Earthen en el África subsahariana, a través del Programa Architecture, Constructive Cultures, and Africa 2009, un esfuerzo basado en un acuerdo Sustainable Development. This program, con entre el Fondo del Patrimonio Mundial de la ceived as a university consortium, is based on the UNESCO, el ICCROM y CRATerre-EAG. En observation that there is a need for more training. cooperación con varias instituciones africanas, It was initiated by UNESCO in 1996 at the este programa desarrolla un método integral para School of Architecture of Grenoble, which has a la formación de un amplio espectro de personas long-standing record in university and professional involucradas en el uso y mantenimiento de este training in the concerned field, and was developed patrimonio, para mejorar las condiciones de su in cooperation with national and international conservación. partners. The program's main goal is to establish La Cátedra de Arquitectura de Tierra de regional and national centers of excellence for spe la UNESCO cialized studies and advanced research, and to Considerando sus actividades y su objetivo develop with them adapted curricula related to de incorporar la conservación de la arquitectura earthen architecture and its conservation. de tierra dentro del curriculo universitario, el The experience and information acquired by Proyecto Terra responde al objetivo principal de the Gaia Project/Project Terra partners through la Cátedra de Arquitectura de Tierra, Culturas the organization of the four international courses Constructivas y Desarrollo Sustentable de la (PAT89, PAT90, PAT92, PAT94) and the regional UNESCO. Este programa, concebido como un course in Trujillo, Peru, (PAT96) should lead to a consorcio universitario, se basa en la observación de la necesidad de contar con más formación. reformulation of the objectives and the contents of Fue iniciado en 1996 por la UNESCO en la the post-graduate course on earthen architecture Escuela de Arquitectura de Grenoble que tiene (presented since 1984 at the School of una larga historia de formación universitaria y Architecture of Grenoble) and make it an interna profesional en el campo en cuestión, y desarrol tional resource for the participants at other lado en cooperación con socios nacionales e regional centers. The PAT99 course will have a internacionales. El programa tiene por objetivo critical and catalytic role in this continuum. It is principal establecer centros regionales y indeed through its development that the Project nacionales de excelencia para estudios especializa Terra partners will synthesize all previous efforts dos e investigación avanzada y desarrollar con by accumulating and structuring the existing ellos un curriculo adaptado a la arquitectura de knowledge that resulted from years of training and tierra y su conservación. hands-on experience. Combined with the explo La experiencia e información que han ration of innovative approaches to training and adquirido los asociados del Proyecto education, organizers of PAT99 hope to develop Gaia/Proyecto Terra gracias a la organización de improved pedagogic and didactic materials that los cuatro cursos internacionales (PAT89, will benefit not only the UNESCO Chair partners PAT90, PAT92, PAT94) y el curso regional en but also a larger network of universities and train Trujillo, Perú, (PAT96) debiera conducirlos a ing centers. reformular los objetivos y contenidos del curso This new phase will allow those concerned de post-grado en arquitectura de tierra (ofrecido with the conservation and future development of desde 1984 en la Escuela de Arquitectura de Grenoble), transformándolo en un recurso inter-
12 CRM No 6—1999 earthen architecture to better face the challenges nacional para los participantes en otros centros presented by the 21 st century. regionales. El Curso PAT99 tendrá un papel crítico y catalizador en este continuo. Más aún, Notes 1 Premier colloque international sur la conservation des gracias a su desarrollo los asociados del Proyecto monuments en brique crue, Yazd, Iran, Conseil Terra podrán sintetizar todos los esfuerzos pre International des Monuments et des Sites et Icomos- vios, acumulando y estructurando el Iran, 25-30 Nov., 1972. conocimiento existente que es resultado de años 2eme colloque international sur la conservation des de formación y experiencia práctica. Combinado monuments en brique crue, Yazd, Iran, Conseil con la exploración de enfoques innovadores en la International des Monuments et des Sites et Icomos- formación y educación, los organizadores del Iran, 6-9 Mar., 1976. curso PAT99 esperan desarrollar materiales 3 US/ICOMOS-ICCROM Adobe Preservation Working Session, Santa Fe, New Mexico, 3—7 Oct., pedagógicos y didácticos perfeccionados que 1977. serán útiles no sólo para los asociados de la 4 Third International Symposium on Mud-brick Cátedra UNESCO, sino también para una vasta (Adobe) Preservation, Ankara, Turkey, ICOM-ICO- red de universidades y centros de formación. MOS Turkish National Committees, 29 Sept.-4 Este nueva etapa permitirá que las personas Oct., 1980. involucradas en la conservación y desarrollo ' International Symposium and Training Workshop on futuro de la arquitectura de tierra puedan the Conservation of Adobe, Lima-Cusco, Peru, The Regional Project on Cultural Heritage and enfrentar mejor los desafíos que les presenta el Development UNDP/UNESCO and ICCROM, nuevo siglo que ya está llegando. 10-22 Sept., 1983. Notas ° Fifth International Meeting of Experts on the 1 Conservation of Earthen Architecture, Rome, Italy, Primer coloquio internacional sobre conservación de monumentos de ladrillos crudos. Yazd, Irán, ICCROM and CRATerre, 22-23 Oct., 1987. Consejo Internacional de Monumentos y Sitios e Sixth International Conference on the Conservation ICOMOS-Irán, 25-30 Noviembre 1972. of Earthen Architecture, Las Cruces, New Mexico, 2 Segundo coloquio internacional sobre conservación US, ICOMOS, GCI, NPS-Southwest Region, The de monumentos de ladrillos crudos, Yazd, Iran, Gaia Project, 14-19 Oct., 1990 Consejo Internacional de Monumentos y Sitios et 8 Seventh International Conference on the Study and ICOMOS-Irán, 6-9 Marzo 1976. Conservation of Earthen Architecture, Silves, 3 Sesión de Trabajo en Conservación de Adobe Portugal, DGEMN, The Gaia Project, and the US/ICOMOS-ICCROM, Santa Fe, Nuevo International ICOMOS Committee for the Study México, 3-7 Octubre 1977. and the Conservation of Earthen Architecture, * Tercer Simposio Internacional de Preservación de 24-29 Oct., 1993. Ladrillos de Barro (Adobe), Ankara, Turquía, Comités Nacionales Turcos ICOM-ICOMOS, 29 Sept.-4 Octubre 1980. Marina Trappeniers, engineer-architect, is Training ' Simposio Internacional y Taller de Formación en Coordinator at CRATerre-EAG, the International Centre Conservación de Adobe, Lima-Cusco, Perú, for Earth Construction, School of Architecture of Grenoble, Proyecto Regional sobre Patrimonio Cultural y France. Desarrollo PNUD/UNESCO e ICCROM, 10-22 Septiembre 1983. Project Terra Partners ° Quinta Reunión Internacional de Expertos en Los asociados al Proyecto Terra Conservación de la Arquitectura de Tierra, Rome, Italia, ICCROM y CRATerre, 22-23 Octubre CRATerre-EAG 1987. 60 avenue de Constantine Sexta Conferencia Internacional sobre B.P. 2636 Conservación de la Arquitectura de Tierra, Las 38036 Grenoble CEDEX 2 Cruces, Nuevo México, US, ICOMOS, GCI, NPS-Southwest Region, Proyecto Gaia, 14—19 France Octubre, 1990 8 ICCROM Séptima Conferencia Internacional sobre el 13, via di San Michele Estudio y Conservación de la Arquitectura de Tierra, Silves, Portugal, DGEMN, Proyecto Gaia y 00153 ROMA RM Comité Internacional ICOMOS para el Estudio y Italy Conservación de la Arquitectura de Tierra, 24-29 Octubre 1993. The Getty Conservation Institute 1200 Getty Center Drive, Suite 700 Marina Trappeniers, architecta-ingeniera, es la Los Angeles, CA 90049-1684 Coordinadora de Entrenamiento en CRATerre-EAG, el USA Centro Internacional para La Construcción de Tierra, en la Escuela de Arquitectura de Grenoble, Francia.
CRM No 6—1999 13 Erica Avrami Building Institutional Alliances Project Terra Establecimiento de Alianzas Institucionales Proyecto Terra Ever since man learnt to build Desde que el hombre aprendió homes and cities around 10,000 hace más de 10.000 años a con years ago, earth has undoubtedly struir casas y ciudades, la tierra ha been one of the most widely-used sido sin duda uno de los materiales construction materials in the world. de construcción más usados en There is hardly an inhabited conti todo el mundo. nent, and perhaps not even a coun Casi no existe continente ni país try, which does not have a heritage habitado que no tenga un patrimo of buildings in unbaked earth, and nio de edificios construidos con even nowadays more than a third of tierra cruda. Más aún, en nuestros all humanity lives in a home built of días más de un tercio de la earth. humanidad vive en casas construi Hugo Houben and Hubert Guillaud* das con tierra. Hugo Houben y Hubert Guillaud* s the preceding quote indicates, there is a wealth of earthen archi omo señala la cita anterior, en tectural heritage the world over todo el mundo existe una gran and thus an enormous challenge riqueza en el patrimonio de la to preservAe this important legacy. From entire arquitectura de tierra, con el con cities to monumental sites to intricate decorated siguientCe enorme desafío que plantea la preser surfaces, the range and complexity of earthen vación de este importante legado. Desde ciudades architectural materials and applications makes enteras a sitios monumentales y superficies de conserving this heritage a formidable task. intrincada decoración, el abanico y complejidad Compounding the problem further are the ram de los materiales y aplicaciones arquitectónicas de pant and rapid excavation of earthen sites, tierra hace de la conservación de este patrimonio unchecked development and encroachment, una tarea de titanes. Agrava este problema la increasing tourism, and a lack of trained profes desenfrenada y rápida excavación en sitios arque sionals. ológicos de tierra, un desarrollo e intromisión Despite the glaring need for a concerted descontrolados, el turismo creciente y la falta de effort on this front, there are relatively few orga profesionales capacitados. nizations dealing with earthen architecture con A pesar de la necesidad de concertar esfuer servation. This may be due in part to the unfor zos en este frente, existen pocas organizaciones tunate and misguided perception that earthen que trabajan en el campo de la conservación de
Earth Construction: A Comprehensive Guide. Earth Construction: A Comprehensive Guide. (London: Intermediate Technology Publications, (London: Intermediate Technology Publications, 1994). 1994).
14 CRM No 6—1999 architecture is a "primitive" form of construction. arquitecturas de tierra. En parte ello puede In academia, earthen architecture is largely absent explicarse por una percepción desafortunada y from courses on history, design, and construction poco atinada de la arquitectura de tierra como technology. With earthen structures constituting una forma "primitiva" de construcción. En los only a fraction of new construction in the indus ambientes académicos no se enseña casi la trialized world, there is no industry to promote arquitectura de tierra en los cursos de historia, and support continued investigation of earthen diseño y tecnología de la construcción. Dado materials and their applications. As such, the sci que las estructuras de tierra constituyen sola Chan Chan, entific and technological research base for earthen mente una fracción de las construcciones Trujillo, Peru. architecture and its conservation is very limited as nuevas en el mundo industrializado, no existe World Heritage compared to that of stone, brick, and timber. una industria que promueva y apoye la investi Site and venue for the Pan- Procedures and information are often borrowed gación permanente en materiales de tierra y sus American from other fields, such as agriculture and road aplicaciones. En sí, la base de investigaciones Course on the building, but significant differences in applica científicas y tecnológicas para la arquitectura de Conservation tion often preclude a direct transfer of technol and tierra y su conservación es muy limitada, si la Management of ogy. The result is a rather fragmented body of comparamos con la de la piedra, ladrillo y Earthen knowledge. madera. Los procedimientos e informaciones Architectural and Through a series of international confer suelen tomarse de otras disciplinas, como la Archaeological Heritage ences, training initiatives, and the formation of agricultura y construcción de carreteras. Sin (PAT96). Photo national and international committees, there has embargo las grandes diferencias en su apli courtesy Michael been in the past two decades considerable cación constituyen a menudo un impedimento Romero Taylor. advancement of the earthen architecture conser práctico para una transferencia directa de tec Chan Chan, vation field. A network of practitioners, scientists, nología. El resultado es un cuerpo de Trujillo, Perú. and academics has developed as a consequence of Sitio de conocimientos fragmentario. Patrimonio these venues that foster the exchange of informa Gracias a una serie de conferencias inter Mundial y tion. However, the increase in institutional com nacionales, iniciativas de formación y la Localidad para mitment lags behind, and so too has the support el Curso creación de comités nacionales e interna Panamericano for larger-scale initiatives and policy reform. cionales, en las dos últimas décadas se ha exper en la Targeting Institutions imentado un notable avance en el campo de Conservación y It has become increasingly clear that institu conservación de la arquitectura de tierra. Como Manejo de Arquitectura tional involvement and cooperation are key in un resultado de estas reuniones se ha ido cre Terrea y developing the type of broad-based support ando una red de expertos, de científicos y Patrimonio needed for the conservation of earthen architec académicos que estimula el intercambio de Arqueológico (PAT 96). Foto ture. Using the experience of Preservación de la informaciones. Sin embargo, existe un retraso 1 cortesía de Architectura de Tierra (PAT) 96, the en el compromiso institucional, al igual que el Michael International Centre for Earth Construction- apoyo para iniciativas a mayor escala real y Romero Taylor. School of Architecture of Grenoble (Centre reformas normativas. Orientación a Instituciones Se ha hecho cada vez más claro que el compromiso y cooperación institucional resul tan claves para desarrollar el tipo de apoyo de amplia sustentación necesario para la conser vación de la arquitectura de tierra. Con la expe riencia de Preservación de la Arquitectura de Tierra (PAT) 96,1 el Centro Internacional de Construcción de Tierra-Escuela de Arquitectura de Grenoble (CRATerre-EAG), el Getty Conservation Institute (GCI) y el Centro Internacional para el Estudio de la Conservación y Restauración del Patrimonio Cultural (ICCROM) iniciaron conversaciones para establecer un programa conjunto de colab oración entre estas entidades destinado al estu-
CRM No 6—1999 15 International de la Construction Terre-Ecole dio y conservación de la arquitectura de tierra. d'Architecture de Grenoble) (CRATerre-EAG), Con una larga historia de intervención en este the Getty Conservation Institute (GCI), and the campo, estas instituciones se han compro International Centre for the Study of the metido a promover el conocimiento y apre Preservation and the Restoration of Cultural ciación del patrimonio de arquitectura de tierra, Property (ICCROM) initiated discussions to reconociendo la fuerza que resulta de la unión establish a collaborative de esfuerzos en un marco de cooperación, el ICCROM/GCI/CRATerre-EAG program for the Proyecto Terra. Habiendo establecido este study and conservation of earthen architecture. nuevo marco de colaboración internacional, las Having a long history of involvement in the field, experiencias institucionales previas como el these institutions are committed to promoting Proyecto Gaia del ICCROM/CRATerre-EAG y the understanding and appreciation of earthen las actividades realizadas por el Getty architecture heritage and have recognized the Conservation Institute en el pasado en este ter potential of uniting efforts in one cooperative reno se insertan hoy en el Proyecto Terra. framework, Project Terra. With this new frame Gracias a sus actividades independientes y work for international collaboration established, colectivas en el campo de la conservación de la previous institutional experiences such as arquitectura de tierra, los miembros del ICCROM/CRATerre- EAG's Gaia Project, as Proyecto Terra han visto que la manera más exi well as the GCI's past activities in the field, are tosa de valorizar recursos y avanzar en este ter unfolding into Project Terra. reno es asociaciarse con otras organizaciones. Es The Project Terra partners recognized— así como el Proyecto estableció un marco para through their independent and collective activi la colaboración conjunta del ICCROM, ties in the field of earthen architecture conserva CRATerre-EAG y el GCI,2 como también con tion—that the most successful means of leverag otras instituciones a través de asociaciones ing resources and developing the field was estratégicas en cuatro áreas de actividad. through partnership with other organizations. As El Proyecto Terra: Misión y such, the project established a framework for Actividades ICCROM, CRATerre-EAG, and the GCI2 to El Proyecto Terra tiene como propósito collaborate with each other as well as with other desarrollar el tema de la conservación del patri institutions though associate partnerships in four monio arquitectónico de tierra como una cien areas of activity. cia, un campo de estudio, una práctica profe Project Terra Mission and Activities sional y un esfuerzo social mediante la coop The aim of Project Terra is to develop the eración institucional en las áreas de conservation of earthen architectural heritage—as investigación, educación, planificación e imple- a science, a field of study, a professional practice, mentación, promoción e investigación. and a social endeavor—through institutional Investigación. En el área de investigación cooperation in the areas of research, education, los esfuerzos se han centrado en establecer el planning and implementation, and advocacy and estado actual de conocimientos en el campo de outreach. la conservación de la arquitectura de tierra e Research. In the area of research, efforts are iniciar nuevas investigaciones, tanto en terreno focused on establishing the current state of como de laboratorio. Como parte de lo ante knowledge in the field of earthen architecture rior, se aplicó una encuesta a personas y organi conservation and on initiating new research in zaciones en todo el mundo con el objetivo de both the lab and field. As part of the former, a recopilar iniciativas y tendencias actuales en la survey has been conducted of individuals and investigación en arquitectura de tierra. Los organizations around the world to establish cur resultados de la encuesta serán resumidos en un rent initiatives and trends in earthen architecture informe del estado de conocimientos que tam research. The results of the survey will be synthe bién incorporará las conclusiones de una sized in a report on the state of knowledge, which revisión crítica de la literatura más reciente y un will also incorporate the outcomes of a critical análisis de la estructura de la disciplina y de las review of recent literature and an analysis of the lagunas y tendencias en este terreno. structure of the discipline and of gaps and trends Esta nueva investigación que coordina el in the field. GCI consiste en el siguiente plan de tres fases:
16 CRM No 6—1999 • caracterización de los materiales de construc ción de tierra y sus propiedades; • análisis e individulización de los factores y mecanismos de decadencia, y • desarrollo y pruebas de alternativas de con servación. Uno de los objetivos básicos de esta inves tigación es lograr una comprensión cabal de los procesos de degradación generados cuando se excavan los restos arqueológicos de las estruc turas de tierra, dejándolos expuestos a la acción ambiental. Un objetivo específico es desarrollar métodos adecuados para mitigar el deterioro de dichas estructuras, a partir de esta comprensión. Las ventajas potenciales en el largo plazo de esta Huaca de la The new research, coordinated by the GCI, investigación son comprender la causa y man Luna, Trujillo, consists of a three-phase plan of Peru. Cleaning era en que se degradan los materiales, generar- • characterizing earthen building materials and and conserva datos a partir de un conjunto de metodologías their properties tion of murals on posibles de intervención que han sido evaluadas recently exca • analyzing and isolating decay factors and vated earthen en el laboratorio y en terreno, y desarrollar pro mechanisms, and architecture. cedimientos analíticos simplificados. • developing and testing possible conservation Photo courtesy Se está evaluando una amplia gama de Michael Romero options. procedimientos analíticos para elegir luego Taylor. A primary objective of this research is to aquellos que puedan producir información que develop an understanding of the nature of the se correlacione con la resistencia relativa a la Huaca de la degradation processes that occur when archeolog- Luna, Trujillo, meteorización de los materiales de tierra ical remains of earthen structures are excavated Perú. Limpieza obtenidos de diferentes sitios históricos arque y conservación and exposed to the environment. A secondary ológicos. Gracias a esta correlación de datos será de murales in objective is to build on this understanding and una excavación posible caracterizar las propiedades críticas develop appropriate methods to mitigate the reciente de responsables de la degradación, lo que a su vez arquitectura deterioration of these structures. The potential servirá para orientar la investigación relativa a terrea. Foto long-term benefits of this research are an under cortesía de técnicas de conservación. standing of why and how earthen materials Michael En la actualidad el GCI explora el interés degrade, the generation of data on a group of Romero Taylor. de instituciones asociadas que deseen colaborar possible intervention methodologies that have en tal esfuerzo de investigación. La colabo been evaluated in the laboratory and in the field, ración puede consistir en realizar análisis parale and the development of simplified analytical pro los o complementarios, en la entrega de mues cedures. tras de materiales y documentación necesaria o A broad range of analytical procedures are en permitir el acceso y apoyo en los sitios, para under evaluation to determine which will yield realizar actividades de pruebas y monitoreo. Las information that can be correlated with the rela organizaciones que estén interesadas en asociarse tive resistance to weathering of earthen materials a esta actividad pueden contactarse al GCI. obtained from various historic archeological sites. Educación. Uno de los objetivos básicos Through this correlation of data, it may be possi del Proyecto Terra en el área de la educación es ble to characterize the critical properties that are desarrollar la arquitectura de tierra como un responsible for the observed tendency toward campo de estudios universitarios. Esto puede degradation, and this in turn will serve to focus lograrse mediante la elaboración y ensayo de research related to conservation techniques. metodologías de formación y materiales didác At present, the GCI is seeking institutional ticos, el desarrollo de un cuerpo docente y el partners to collaborate in the research effort. establecimiento de un consorcio universitario. Collaboration may consist of conducting parallel La década que cubre el legado PAT,^ el or complimentary analyses, furnishing material curso de post-grado en CRATerre-EAG y la samples and requisite documentation, and/or Cátedra de Arquitectura de Tierra recién inau-
CRM No 6—1999 17 providing access to and support at sites for testing gurada por la UNESCO son una base sólida and monitoring. Organizations interested in part que permite ir cumpliendo con este objetivo. nering in this endeavor should contact the GCI. (Para mayores informaciones sobre estas inicia Education. In the area of education, a pri tivas de formación véase el artículo de mary objective of Project Terra is to develop Trappenier, p. 7). Entre otras actividades educa earthen architecture as a field of study at the uni tivas están las reuniones de grupos pequeños de versity level. This is to be achieved through the especialistas, centradas en problemas específicos elaboration and testing of training methodologies de impacto en el terreno, y también una inicia and didactic materials, development of faculty, tiva que busca uniformar la terminología rela and building of a university consortium. The ten- cionada con la arquitectura de tierra y su con year PAT legacy, the post-graduate course at servación. Este campo sufre del uso de términos CRATerre-EAG, and the newly inaugurated inadecuados y coloquiales, tanto en la práctica UNESCO Chair on Earthen Architecture consti como en la literatura. Con la colaboración de tute a strong foundation from which this objec las organizaciones que trabajan con arquitectura tive is being pursued. (For more information on de tierra y de otras que investigan el vocabu these training initiatives, see Trappeniers' article, lario arquitectónico y de las ciencias de la con P-7.) strucción se espera establecer un consenso en Additional educational activities include relación con la terminología. meetings of small groups of specialists to focus on Planificación e Implementación. En el specific issues impacting the field, as well as an Proyecto Terra, el aspecto de planificación e initiative aimed at standardizing terminology implementación abarca el desarrollo, pruebas y related to earthen architecture and its conserva aplicación de metodologías específicas para la tion. The field has long suffered from the use of conservación y manejo de sitiosm de arquitec inaccurate terms and colloquialisms both in prac tura de tierra. La metodología de planificación tice and in literature. Through collaboration with basada en valores que presentara el curso organizations dealing with earthen architecture as PAT96 se ha aplicado a un plan de manejo para well as those dealing with vocabularies related to el sitio Chan-Chan^ que asumió el Instituto architecture and construction sciences, it is hoped Nacional de Cultura-La Libertad (INC-LL) con that both momentum and consensus regarding el respaldo de la UNESCO y de los asociados such terminology can be built within the field. del Proyecto Terra. Se adaptó la misma tec Planning and Implementation. The plan nología para aplicarla en la Joya de Cerén" en ning and implementation component of Project El Salvador, a través de un proyecto de coop Terra involves the development, testing, and eración del GCI y Concultura. El Proyecto application of methodologies specific to the con Terra pretende, a través del desarrollo de estos y servation and management of earthen architec otros proyectos de referencias, mantener un cri tural sites. The value-driven planning methodol terio interdisciplinario integrado para la conser ogy advanced by the PAT96 course has been vación y manejo que responda a las necesidades applied to the development of a management específicas del patrimonio arquitectónico de plan for Chan Chan' undertaken by the Instituto tierra. Nacional de Cultura—La Libertad (INC-LL), Promoción y Extensión. Las actividades with the support of UNESCO and the Terra de promoción y extensión del Proyecto Terra Project partners. The same methodology is being han permitido que distintas instituciones cul adapted for application at Joya de Cerén" in El turales exploren las posibilidades de organizar Salvador through a cooperative project of the una exposición internacional sobre arquitectura GCI and Concultura. Through the development de tierra centrada en su historia, su conser of these and other reference projects, Project vación y su continuidad en el futuro. Esta ini Terra plans to develop an integrated, interdisci ciativa es una continuación de la exitosa exposi plinary approach to conservation and manage ción "Des architectures de terre. Tradition et ment that meets the particular needs of earthen modernité" inaugurada en 1981 en el Centro architectural heritage. Georges Pompidou y que ha sido presentada en Advocacy and Outreach. Through the 22 ciudades de 14 países. Continúan las solici advocacy and outreach component of Project tudes de préstamo, aunque ya la exposición y su Terra, several cultural institutions are exploring mensaje han sido probablemente superados. La
18 CRMN06—1999 possibilities for the development of an interna nueva exposición se fundará en las experiencias tional exhibition on earthen architecture that y éxito de su antecesora, poniendo un acento concentrates on its history, its conservation, and fuerte en la conservación, tema que no fue its continuity in the future. This proposed ven tratado en la primera versión. ture follows the very successful exhibition, "Des Además, este componente del Proyecto Architectures de Terre—Tradition et Modernite," Terra incluirá actividades de extensión rela which opened in 1981 at the Centre Georges cionadas con áreas específicas de trabajo o Pompidou and has been presented in 22 cities in colaboración, como los esfuerzos de extensión a 14 countries. Loan requests still continue la comunidad de Trujillo en el curso PAT 96, although the exhibition and its message are quite las demostraciones o informaciones de proyec outdated. This new exhibition would build upon tos que se presentan en los sitios de investi the lessons and success of its predecessor, and it gación. would include a strong emphasis on conserva Conclusiones tion, an issue that was not addressed previously. El sector y sus necesidades deben verse In addition, this component of Project desde una perspectiva global para poder respon Terra may include outreach activities related to der a los desafíos planteados por la conser specific areas of work or collaboration, such as vación del patrimonio arquitectónico mundial community outreach efforts in Trujillo, Peru, for de tierra. No existe, ni existirá jamás, un the PAT99 course, demonstrations, or project método totalmente seguro para preservar los information made available at research sites. materiales y estructuras de tierra. La variedad Conclusions de contextos culturales y físicos donde se To address the challenges posed by the con encuentra el patrimonio, como también la servation of the world's earthen architectural her monumentalidad, escala y complejidad de sus itage, it is necessary to view the field and its manifestaciones impiden abordarlo con un cri needs holistically. There is not—nor will there terio técnico único. Al incentivar la colabo ever be—a surefire method to preserve earthen ración multilateral y multidisciplinaria en materials and structures. The variety of cultural diversas, aunque limitadas, áreas de actividad, and physical contexts in which this heritage se espera que el Proyecto Terra logre desarrollar resides, as well as the monumentality, scale, and el campo de la conservación de la arquitectura complexity of its manifestations, preclude a sin de tierra de manera integral y abierta al futuro. gularly technical approach. By fostering multilat eral and multidisciplinary collaboration through Notes several—if limited—areas of activity, it is hoped 1 Curso Panamericano sobre la Conservación y that Project Terra will develop the field of earthen Manejo del Patrimonio Arquitectónico Histórico- Arqueológico de Tierra, llevado a cabo en Trujillo, architecture conservation in an integrated and Perú entre el 10 de noviembre y el 13 de diciem future-oriented fashion. bre de 1996 en conjunto con el Instituto Nacional de Cultura. Notes 2 El equipo del proyecto GCI está integrado por 1 Curso Panamericano sobre la Conservacications, Giora Solar y Alberto Tagle (Codirectores), Erica 1994). It is hoped that Project Terra will develop Avrami (Gerente del Proyecto), Bill Ginell the field of ea, a five-week course hosted in Trujillo, (Científico de Mayor Antigüedad), Gaetano Peru, November 10-December 13, 1996, in collab Palumbo (Especialista del Proyecto), Evin Erder oration with the Instituto Nacional de Cultura. (Investigador Becado) y Anna Zagorski (Asociada 2 Members of the GCI project team are Giora Solar al Proyecto). and Alberto Tagle (Co-Directors), Erica Avrami ^ Bill Ginell y Carlos Navarro-Rodriguez, "Earthen (Project Manager), Bill Ginell (Senior Scientist), Materials Test Plan", Getty Conservation Gaetano Palumbo (Project Specialist), Evin Erder Institute, Los Angeles, California. (Fellow), and Anna Zagorski (Project Associate). 4 PAT89, PAT90, PAT92, PAT94 en Grenoble, ' Bill Ginell and Carlos Navarro-Rodriguez, "Earthen Francia (CRATerre-EAG e ICCROM como Materials Test Plan," Getty Conservation Institute, GAIA); PAT96 en Trujillo, Perú (CRATerre-EAG Los Angeles, Calif. e ICCROM como GAIA y el Instituto Nacional 4 PAT89, PAT 90, PAT 92, PAT 94 in Grenoble, de Cultura); PAT99 en Trujillo, Perú (CRATerre- France (CRATerre-EAG and ICCROM as Gaia); EAG, ICCROM y GCI como Terra y el Instituto PAT 96 in Trujillo, Peru (CRATerre-EAG and Nacional de Cultura La Libertad). ICCROM as Gaia, GCI, and the Instituto Nacional ° Chan Chan es un complejo arqueológico de tierra de Cultura); PAT 99 in Trujillo, Peru (CRATerre- perteneciente a la cultura Chimu en Trujillo,
CRM No 6—1999 19 EAG, ICCROM, and GCI as Terra and the Instituto Perú, el cual abarca 14 Km2 de superficie (c. entre Nacional de Cultura—La Libertad). los siglos 9 y 14 D.C.). 5 Chan Chan is a l4-km2 earthen archeological com ° Joya de Ceren es un emplazamiento arqueológico plex (ca. 9-14 cent. A.D.) of the Chimu culture in Maya (c. año 600 D.C.) de construcción de tierra no Trujillo, Peru. monumental, cerca de San Salvador, El Salvador. " Joya de Cerén is a Mayan archeological site (ca. 600 A.D.) of non-monumental earthen construction near San Salvador, El Salvador Erica Avrami es una especialista de proyectos con el Instituto de Conservación Getty. Para más información, por favor póngase en contacto con ella a ésta dirección: Erica Avrami is a project specialist for the Getty 1200 Getty Center Dr., Ste. 700, Los Angeles, CA Conservation Institute. For more information, please con tact her at 1200 Getty Center Dr., Ste. 700, Los Angeles, 90049; o con Alejandro Alva, ICCROM, 13 via di San CA 90049; Alejandro Alva, ICCROM, 13 via di San Michele, 00153 Roma RM, Italy; o con Hugo Houben, Michele, 00153 Roma RM, Italy; or Hugo Houben, CRATerre-EAG, B.P. 53, 38092, Villefontaine Cedex, CRATerre-EAG, B.P. 53, 38092, Villefontaine Cedex, France. France.
US/ICOMOS Comité US/ICOMOS Specialized Committee on Especializado en Earthen Architecture Arquitectura de Tierra he International Council on l Consejo Internacional de Monumen TMonuments and Sites, (ICOMOS), is Etos y Sitios ICOMOS, (International a nongovernmental organization of professionals Council on Monuments and Sites) es una orga and individuals active in preserving the world's nización no gubernamental de profesionales e cultural heritage. Its principal objectives are to individuos involucrados activamente en la bring together professional specialists from preservación del patrimonio cultural del mundo. around the world as a forum for professional Sus objetivos principales son reunir a expertos dialogue and exchange; to collect, evaluate and profesionales de todo el mundo en un foro que disseminate information on preservation princi haga posible el diálogo e intercambio profe ples, techniques and policies; to cooperate with sional; recopilar, evaluar y divulgar la informa international and national authorities on the ción sobre principios, técnicas y políticas de establishment of documentation centers special preservación; cooperar con las autoridades izing in preservation; to work for the adoption nacionales e internacionales para establecer cen and implementation of international conven tros de documentación especializados en conser tions; and to put the expertise of professionals vación; trabajar por la adopción e implementa- and specialists at the service of the worldwide ción de las convenciones internacionales; y poner community. los conocimientos expertos de profesionales y US/ICOMOS is the United States com especialistas al servicio de la comunidad mundial. mittee of ICOMOS. It is one of 95 such US/ICOMOS es el Comité de ICOMOS national committees that form a worldwide de los Estados Unidos. Es uno de los 95 comités alliance for the study and conservation of his nacionales del mismo estilo que forman una toric buildings, districts, and sites. US/ICO alianza mundial para el estudio y conservación MOS has several specialized committees that de edificios, distritos y sitios históricos. US/ICO were organized to offer specific expertise in con MOS cuenta con varios comités especializados servation areas. The US/ICOMOS Specialized organizados para ofrecer asesoría experta en áreas Committee on Earthen Architecture is one of de conservación. El Comité US/ICOMOS these committees. For more information, please Especialista en Arquitectura de Tierra es uno de access the IS/ICOMOS web page at
20 CRM No 6—1999 Michael Romero Taylor Earthen Architecture Traditions in New Mexico Tradiciones de Arquitectura de Tierra en Nuevo México
Jacal construc tion unearthed n the United States, New Mexico can entro de los Estados Unidos, during excava boast of many of eatthen architectute's tions of the Hyde Nuevo México puede Expedition at the crown jewels, which ate scattered enorgullecerse de poseer turn of the cen throughout its landscape; among the muchas de las joyas de la tury at Pueblo architecturaI l gems are the Palace of the coronDa en arquitectura de tierra repartidas por Bonito, Chaco Culture National Governors in Santa Fe (the oldest continuously todo su territorio; entre las gemas arquitectóni Historical Park. occupied public building dating to 1609), the cas están el Palacio de los Gobernadores en Photo courtesy Old Santa Fe Trail Building (a regional office for Santa Fe, el edificio público más antiguo ocu Department of Library Services, the National Park Service built in the 1930s and pado sin interrupciones, que data de 1609; el American the largest adobe office complex in the United Old Santa Fe Trail Building, una oficina Museum of States), and Taos Pueblo (a multi-storied adobe regional del Servicio Nacional de Parques con Natural History. pueblo occupied for more than 500 years; Taos struida en los años 30, el complejo de oficinas Construcción de Pueblo recently was placed on the World de adobe más grande de los Estados Unidos y el jacal excavado al Heritage List). These well-known monuments are Taos Pueblo, un pueblo de adobe de varios principio del siglo but a small part of the Southwest's extensive her pisos habitado por más de quinientos años que durante la expe dición Hyde en itage in building with earth that dates back at recientemente ha sido incluido en la World Pueblo Benito, least 2,000 years. Heritage List. Estos famosos monumentos no Chaco Culture The styles and methods that have been used son sino una pequeña muestra del gran patri National Historical Park. in earthen construction in New Mexico are as monio de construcción en tierra del Sudoeste Foto cortesía del varied as the people who built the structures. The que se remonta al menos a 2,000 años atrás. American region has been a settling place for many immi Los estilos y métodos que se han utilizado Museum of Natural History. grants, some of whom used the Rio Grande en la construcción de tierra en Nuevo México son tan variados como la gente que levantó las estructuras. Son muchos los inmigrantes que se asentaron en esta región, usando el valle del Río Grande como el corredor principal de trans porte. Los primeros habitantes del área llegaron aquí aproximadamente en el 10.000 A.C.; los siguieron oleadas sucesivas de indígenas ameri canos procedentes de las praderas y luego inmi grantes y comerciantes de la región mesoameri- cana. Los españoles y otros grupos europeos trajeron luego con ellos nuevas ideas de con strucción con tierra y asimilaron las tradiciones locales en los estilos prevalecientes en esa época. En Nuevo México, como en muchas partes del mundo, la tradición de construir con tierra abarca una gran variedad de técnicas a través de los siglos; entre las técnicas y materi-
CRM No 6—1999 21 Valley as the main transportation corridor. The ales están la manipostería de adobes, el jacal, y first people to have inhabited the area were here los ladrillos de adobe moldeados manualmente about 10,000 B.C.; they were followed by subse y encofrados. quent waves of other American Indians from the Las primeras estructuras construidas en Plains and then by immigrants and tradesmen Nuevo México probablemente fueron casas- from Meso-America. Spaniards and other foso: estructuras semisubterráneas revocadas Europeans later brought with them many new con barro, construidas en parte dentro de la ideas for building with earth, and they assimi tierra, con techo de madera, ramas y tierra. En lated local traditions into styles that were preva ocasiones los muros subterráneos de tierra lent at the time. tenían un revestimiento de manipostería de In New Mexico, as in many parts of the adobe. Se puede encontrar restos arqueológicos world, the tradition of building with earth has de este tipo de viviendas en casi todo Nuevo involved a variety of techniques through the cen México y en el resto de la parte sudoccidental turies; among the techniques and materials are de lo que hoy son los Estados Unidos. coursed adobe, jacal, and hand-molded and Paulatinamente se ha ido sumando más y form-molded adobe bricks. más información sobre este tipo de vivienda y The first structures built in New Mexico sus variaciones en el tiempo y en distintas were most likely pit houses: semi-subterranean regiones, como consecuencia de excavaciones mud-plastered structures, built partially into the arqueológicas de recuperación previas a la con ground, with a timber, brush, and dirt roof. strucción de carreteras y otros proyectos de Sometimes the subterranean dirt walls were obras públicas. En excavaciones recientes real veneered with coursed adobe. Archeological rem izadas en las afueras de Santa Fe, una ciudad nants of these types of dwellings can be found in que para muchos de nosotros es el epítome de practically all parts of New Mexico and to the la arquitectura de adobe, se han encontrado rest of the southwestern part of what is now the ejemplos de este tipo de viviendas que datan al United States. More and more information on menos de 2,000 años atrás. this type of dwelling and its variations through La construcción de casas-foso prevaleció time is becoming available, a consequence of sal en Nuevo México hasta alrededor del siglo III vage archeological excavations effected by the de nuestra era, en que se comenzó a construir construction of roads and other publicly funded estructuras sobre la superficie con los materiales projects. Examples of such dwellings that are at disponibles; algunas se construyeron en piedra, least 2,000 years old have been found recently pero hubo muchas de tierra. La mayoría de through excavations on the outskirts of Santa Fe, estas estructuras de superficie se hicieron con la a town that is for many of us in this country the técnica de la "manipostería de adobe" conocida epitome of adobe architecture. a veces como "adobe amasado" (puddled Pit house construction was prevalent in adobe). Estas estructuras de hiladas de adobe se New Mexico until about the third century A.D., hicieron con barro semi duro usado para crear at which time people began to build surface hiladas moldeadas manualmente. Muchos structures using the available materials at hand; pueblos grandes de adobe que tenían hasta some were made of stone, but many were made 2.000 viviendas se construyeron con esta téc of earth. The majority of these surface structures nica. were made using the "coursed adobe" technique, Aparte de la técnica de construcción con sometimes referred to as "puddled adobe." These hiladas de adobe, existieron varias técnicas doc coursed adobe structures were made by using umentadas arqueológicamente de construcción semi-stiff mud to create hand-formed courses. con tierra anteriores a la llegada de los grupos Many large earthen towns, which sometimes con europeos a esta región. Entre ellas destaca la tain up to 2,000 rooms, were made using this técnica del jacal en la que se anclan en el suelo technique. postes rectos, rellenando los espacios con barro. In addition to the coursed adobe style of Algunas estructuras de jacal que se han descu building, there are a number of other archeologi- bierto gracias a las excavaciones arqueológicas cally documented techniques used to build with aparecen en un entorno de pueblos de casas- earth that predate the European's arrival in the foso, mientras que, de acuerdo a la docu region. Among the techniques was jacal, in which mentación, existen otras que hacen las veces de
22 CRM No 6—1999 upright posts are anchored in the ground and in muralla divisoria dentro de estructuras de filled with mud. Some of the jacal structures that sillería de piedra, como en Pueblo Bonito en el have been revealed through archeological excava Parque Nacional de la Cultura Chaco. Durante tions are associated with pit house villages while todo el período de asentamiento europeo se others have been documented as interior dividing continuó la tradición de construir jacales. walls within stone masonry structures such as at Muchas viviendas de los inicios de la colonia Pueblo Bonito in Chaco Culture National española eran de jacal; más aún, en muchas Historical Park. The tradition of building jacales ocasiones las primeras viviendas que construían continued through the European settlement of los colonos al llegar a un lugar eran de jacal the area. Some of the early Hispanic dwellings porque son relativamente fáciles de construir si were jacales; indeed, many times the first type of las comparamos con la construcción de ladrillos dwelling settlers constructed when they arrived at de adobe que requiere mucho más tiempo. a building site was jacal because of its relative ease Por siglos antes de la llegada de los of construction compared to the more time- españoles se usaban bloques de adobe mold intensive adobe brick construction. eado como material común de construcción en Prior to the arrival of the Spanish, form- varias regiones mesoamericanas y en la región molded adobe bricks had been for centuries a de la costa Pacífico de América del Sur. Esta common type of construction material in many tradición no se difundió hacia ni por todo el parts of Meso-America and the Pacific Coast sudoeste de los Estados Unidos de América. Region of South America. This tradition had not Sin embargo, en el sudoeste pre-europeo spread to the southwestern part of North sí existieron construcciones en adobe moldeado America. manualmente. Según su forma y tamaño los Hand-molded adobes in the pre-European informes arqueológicos le han dado distintos Southwest did exist, however. Depending on nombres, entre ellos el de "adobe lomo de tor their shape and size, the bricks have been called tuga" (ladrillos rígidos moldeados a mano cuya
n la mayoría de las regiones de los EEstados Unidos en que se usa n most regions of the United States ampliamente el adobe como material de Iwhere adobe is widely used in con construcción, se han establecido las especi struction, locally adopted amendments to ficaciones normales de construcción que the Uniform Building Code establish stan son modificaciones locales al Código dard building specifications. In New Uniforme de Construcción. En Nuevo Mexico, specifications for adobe are covered México la Sección 2413 del Código de in Section 2413 of the 1991 New Mexico Construcción de Nuevo México de 1991 Building Code. The first version was incluye las especificaciones para construc- approved and adopted by the Construction cioes de adobe. La primera versión fue Industries Division in 1977. Prior to this aprobada y adoptada en 1977 por la 1977 version, which was developed under División de Industrias de Construcción. the auspices of the adobe industry and writ Previo a esta versión de 1977 desarrollada ten by a team of four New Mexican adobe con el patrocinio de la industria del adobe y experts, the section on adobe had been redactada por un equipo de cuatro expertos regarded as severely limited and inconsis en adobe de Nuevo México, se estimaba tent in its coverage of the material and its que la sección sobre el adobe era excesiva specifications. mente limitada y poco coherente en su cobertura del material y especificaciones. Smith, Edward W. and George S. Austin, Modern Adobe in New Mexico. Santa Fe, Smith, Edward W. y George S. Austin, Modern N.Mex.: New Mexico Energy, Minerals, and Adobe in New Mexico. Santa Fe, N.M.: New Natural Resources Department, 1996. Mexico Energy, Minerals, and Natural Resources Department, 1996.
CRM No 6—1999 23 parte superior es convexa y la inferior cóncava) y "de rollo vienes". En el siglo XVII los españoles difundieron en Nuevo México la tradición de construcción con ladrillos de adobe moldeado.. Hacían los ladrillos tal como lo hace la gente en otras partes del mundo, colocando una mezcla de arena, barro, arcilla y agua dentro de moldes de madera; luego agregaban paja para minimizar el agrietamiento típico del curado y agregarle resistencia. Los ladrillos de adobe se dejaban secar al sol antes de usarlos para levantar muros unidos con mortero de tierra. La durabilidad de estos adobes dependía del tipo de tierra usado: por ejemplo, los que tenían un alto contenido de caliche (carbonato de calcio) han durado various names, including "turtle back adobes" Adobe buildings mucho más tiempo que los ladrillos que carecen fronting street (stiff, hand-molded bricks with a convex top and de este aglomerante natural. Los que tienen line on Canyon concave bottom) and "Vienna-roll shaped," in gran cantidad de arcillas no expansivas han Road, Santa Fe, archeological reports. New Mexico. durado más tiempo que los adobes con mayor Photo courtesy By the 17th century, Spaniards in New mezcla de arena y barro, sin la cantidad de New Mexico Mexico had popularized the tradition of building arcilla suficiente para servir de aglomerante. Historic with form-molded adobe bricks. They made the Preservation La mayoría de las estructuras construidas Division. bricks as people do in other parts of the world by en los siglos XVII, XVIII y comienzos del siglo placing mixed sand, silt, clay, and water into Edificios de XIX se hicieron con jacal o ladrillos de adobe. adobe a la largo wooden molds; straw was added to minimize Los patrimonios constructivos del de Canyon cracking when curing and to add strength. The Mediterráneo e indígena americano se unieron Road, Santa Fe, adobe bricks were then left to sun-dry before New Mexico. en una sola práctica para levantar casas de una being used to build walls laid with earthen mor Foto cortesía sola planta con sus habitaciones en línea y New Mexico tar. The durability of these adobes depended on varias puertas que permiten acceder a las Preservation the type of soil used. Those with a high amount Division. habitaciones individuales y al exterior. Solían of caliche (calcium carbonate), for example, have construirse con la fachada continua que da lasted much longer than those without such a directamente sobre la calle de un pueblo o a lo natural binder. Those with significant amounts of largo de un camino, siguiendo un trazado rural non-expanding clays have lasted longer than más lineal en los asentamientos. Los edificios those with more of a sand/silt mix without suffi más grandes tenían forma de U o de cuadrado cient clay to serve as a binder. con una puerta principal que conducía a un The majority of structures built in the 17th, patio abierto y dependencias. 18th, and early part of the 19th centuries were built mostly of jacal or adobe brick. The tradi A mediados del siglo XIX llegaron al tions were a blend of Mediterranean and indige sudoeste los comerciantes y colonos de origen nous building traditions. Many of the dwellings anglosajón que venían del Este por el camino consisted of rooms in a single line with multiple de Santa Fe. Traían con ellos nuevas ideas y doors giving access to individual rooms and the materiales de construcción que se incorporaron exterior. These often were built fronting the street a las tradiciones hispana e indígena. La llegada in a town or along the road in a more linear rural del ferrocarril a Nuevo México cerca de 1870 settlement pattern. Many of the larger buildings puso más a mano elementos como hojalata cor were made in the shape of a U or a square, with a rugada, cemento Portland, clavos cuadrados, main door leading to an open patio, and out vidrios para ventanas, tablones de madera y buildings in back. ladrillos cocidos. During the mid-19th century, Anglo traders Construcción contemporánea de and colonists from the East who had traveled the tierra en Nuevo México Santa Fe Trail arrived in the Southwest; with En Nuevo México se ha dado una con them came new ideas and building materials, tinuidad en la construcción con tierra ya que se
24 CRM No 6—1999 which blended with the existing Hispanic and sigue usando hoy, en menor proporción que Native American traditions. The arrival of the antes por cierto, especialmente si tomamos en railroad to New Mexico in the 1870s made such cuenta los demás tipos de materiales de con items as corrugated tin, Portland cement, cut strucción que se han popularizado desde la nails, window glass, milled lumber, and burned Segunda Guerra Mundial. Nuevo México es brick more readily available. hoy el mayor productor y consumidor de ladril Contemporary Earthen Construction in los de adobe en los Estados Unidos. Cada año New Mexico de la década de 1980 se fabricaron entre tres y There has been a continuum in building cuatro millones de ladrillos de adobe y bloques with earth in New Mexico, although proportion de tierra prensada en Nuevo México. En el ately less so than before especially when one con estado existen más de 59.000 construcciones de siders the other types of building materials that adobe que representan un tercio de las vivien have been popularized since World War II. New das de adobe de los Estados Unidos. Aún existe Mexico is currently the largest producer and con gente que produce sus propios adobes para con sumer of adobe bricks in the United States. Each struir sus casas. La mayoría de las constructoras year during the 1980s, three to four million compra ladrillos de adobe hechos en fábricas adobe bricks and pressed-earth blocks were pro comerciales de adobe repartidas por todo el duced in New Mexico by commercial manufac estado. El principal ladrillo estándar de adobe turers. producido y utilizado en Nuevo México mide 4 More than 59,000 adobe buildings, repre x 10 x 14 pulgadas y pesa aproximadamente 30 senting one-third of the adobe dwellings in the libras. United States, are in New Mexico. Occasionally, En Nuevo México la mayor parte de los backyard adobe producers still build their own edificios de adobe se construyeron con ladrillos homes. Today most builders purchase adobe de adobe tradicional o semiestabilizadmo. Entre bricks from commercial yards located throughout otros materiales de tierra existen los ladrillos de the state. The principal standard-size adobe brick adobe estabilizado, bloques de tierra prensada y produced and used in New Mexico measures 4x10 tierra apisonada (pisé). El ladrillo de tierra x 14 inches and weighs approximately 30 pounds. prensada se está usando cada vez más porque Most adobe buildings in New Mexico are resulta tan barato como construir con paredes made from traditional adobe brick or from semi- de madera o con bloques de concreto de stabilized adobe brick. Other earthen media cenizas. Aunque la mayoría de los constructores include stabilized adobe bricks, pressed-earth están muy acostumbrados a usar el ladrillo blocks, and rammed earth (pise). The pressed- tradicional de adobe moldeado, el uso intensivo earth block is becoming increasingly popular de mano de obra requerido para esta técnica, because building with it can be as affordable as sobre todo en comparación con otros métodos building with a wood frame or with cinder de construcción los ha hecho buscar técnicas blocks. Even though the traditional molded alternativas de construcción con tierra, como adobe brick is what most earthen builders are los bloques prensados o tierra apisonada. used to, the reality of the labor intensiveness of Preservación de la arquitectura de this technique, especially when compared with tierra en Nuevo México other building methods, is making builders look Si están bien protegidos de la humedad at alternative earth building techniques such as una construcción de tierra puede durar por pressed block and rammed earth. miles de años. La cita tantas veces repetida de Preservation of Earthen Architecture in que "una construcción de tierra solamente New Mexico necesita tener un buen sombrero y un buen par Buildings of earth can last thousands of de botas" nos recuerda que los adobes sólo years if protected from moisture. The often requieren un buen techo y buenas fundaciones repeated euphemism "All an adobe building para protegerlos del clima. needs is a good hat and good boots" reminds us Se han hecho numerosos intentos para dar that adobes only need a good roof and a good con la fórmula mágica que preserve las con foundation to protect them from the weather. strucciones de adobe, sin embargo, las mejores Through the years there have been numerous técnicas son mantener seco el adobe, un man attempts to come up with magic elixirs for pre- tenimiento rutinario y usar materiales compati-
CRM No 6—1999 25 bles al reemplazar las secciones deterioradas de un muro. En Nuevo México los expertos en preser vación de adobe han descubierto que los revo ques de cemento que se aplicaron casi umver salmente a las estructuras de adobe después de la Depresión y Segunda Guerra Mundial tienen sus desventajas, entre ellas impedir la evapo ración de la humedad que penetra a través de las grietas. Es común encontrar grietas causadas por la diferencia de los coeficientes de expan sión/contracción inherentes a dos materiales distintos. También han descubierto que los revoques de tierra son los mejores revoques, siempre que estén protegidos de los elementos Deteriorating serving adobe buildings, but the techniques that del clima por una saliente del techo o se le haga adobe buildings, work best are keeping the adobe dry, providing Taos County, una mantención cíclica cada dos o tres años, de New Mexico. routine maintenance, and using compatible mate estar expuestos. En Nuevo México está ocur Photo courtesy rials when replacing deteriorated sections of wall. riendo un cierto renacimiento, con la reintro New Mexico In New Mexico, practitioners of adobe State ducción del yeso de cal que se usaba como pro preservation are realizing that the cement plasters Monuments, tección de las superficies de adobe durante los Museum of New that were applied almost universally to adobe períodos de la Colonia y Territorial hispánicos. Mexico. structures after the Depression and World War II En México enseñan esta técnica los maestros, have their drawbacks, one of which is the inhibi Edificios de quienes siguen hoy calcinando y apagando su adobe deterio tion of the evaporation of moisture that enters propia cal. through cracks. Cracking is common, and it is rando, Taos En muchas regiones del mundo se prefiere County, New caused by the differential expansion/contraction Mexico. Foto la arquitectura de tierra por su comodidad, coefficients inherent in the two dissimilar materi cortesía New facilidad para construir y bajo costo. Es un als. Practitioners are also realizing that earthen Mexico State material de construcción realmente sustentable, Monuments, plasters are the best renders as long as they are porque se procesa sin dañar el medio ambiente, Museum of New protected from the elements by a roof overhang, Mexico. especialmente si consideramos la energía uti or cyclically maintained every two to three years lizada en la fabricación y transporte de diversos if left exposed. A renaissance of sorts is taking tipos de materiales de construcción. Si la place in New Mexico with the re-introduction of estructura se hace con tierra disponible en el lime plaster, which was used to protect the sur lugar de construcción, la energía gastada en faces of adobes during the Spanish Colonial and transportar el adobe es irrelevante. Las estruc Territorial periods. This traditional technique is turas de tierra se adaptan a todo tipo de being re-introduced from Mexico. vivienda, construyendo con ella casas con cale In many parts of the world, earthen archi facción solar, muros de patios, construcciones tecture is the architecture of choice because of its para haciendas y ranchos y edificios comer comfort, ease in construction, and low cost. It is ciales. Las estructuras actúan como cortafuego y truly a sustainable building material in that its tienen excelente aislación sonora. utilization is an environmentally friendly process La construcción con tierra es la esencia especially when one considers energy represented misma de la sustentabilidad y afortunadamente in the making and transport of various types of en Nuevo México se conoce cada vez más de su building materials. If the structure is made from viabilidad para viviendas (véase el artículo de the soil on site, the energy involved in adobe Crocker, p. 27): Nuevo México tiene un código transport is negligible. Earthen structures are de construcción en adobe (en revisión actual adaptable to all types of housing, including solar- mente) que hace más fácil aún su adopción por earthen buildings, yard walls, farm and ranch build la industria respectiva. La futura revisión de los ings, and commercial buildings. The structures are códigos reflejará con mayor propiedad el uso de fire resistant and well insulated against noise. materiales asociados al adobe (véase cuadro Building with earth is the essence of sus- complementario). Se espera que otras regiones tainability, and fortunately in New Mexico there
26 CRM No 6—1999 is a growing awareness of its feasibility in housing del país sepan reconocer la practicidad y como (see Crocker article, below). New Mexico has an didad de este material de construcción de adobe building code (that is currently under revi viviendas para el siglo XXI. sion), which makes it even more practical for the building industry to adopt. The future revision of Bibliografía the codes will more closely reflect the appropriate Moquin, Michael. "From Bis Sa Ani to Picuris, Early Pueblo Adobe Technology of New Mexico and use of materials in association with adobe (see the Southwest." Traditions/The Adobe Journal box, p. 23), and it is hoped that other areas of the Winter:8 (1992). country will recognize the practicality and com Smith, Edward W. and George S. Austin. Modern fort of this building material for housing in the Adobe in New Mexico. Santa Fe, N.M.: New 21st century. Mexico Energy, Minerals, and Natural Resources Department, 1996. Bibliography Moquin, Michael. "From Bis Sa Ani to Picuris, Early Michael Romero Taylor es Subdirector de New Mexico Pueblo Adobe Technology of New Mexico and the State Monuments, unidad del Museum of New Mexico Southwest." Traditions/The Adobe Journal de Santa Fe, y es miembro de US/ICOMOS. Winter:8(1992). Smith, Edward W. and George S. Austin. Modern Adobe in New Mexico. Santa Fe, N.Mex.: New Mexico Energy, Minerals, and Natural Resources Department, 1996.
Michael Romero Taylor is the Deputy Director, New Mexico State Monuments, a unit of the Museum of New Mexico in Santa Fe, and he is a member of US/ICOMOS.
Ed Crocker Earthen Architecture and Incentives at Acoma Pueblo
arthen architectural heritage is the use of deep tradition. Incorporating and more than artifact, and the conser adapting the ways of the past to the imperatives vation of that heritage implies far of the present is heritage conservation in its most more than the treatment of mater esteemed form. The past, after all, is prologue. ial cultureE. On a small planet occupied by more If we look at heritage preservation as a liv than five billion people, the immense utility and ing, pertinent, and creative pursuit, we need to versatility of earthen architecture is underscored help forge a mutually beneficial league joining by the knowledge that nearly half those people the arts (yes, the liberal ones to be sure, but more live in or regularly use earthen buildings of one explicitly in this case the plastic ones) and the sort or another. Even if poverty is often the dri social sciences. When we speak of "traditional ving force behind the use of earth, the choice of technologies," the context is clearly anthropologi material for two and one-half billion people cal within a compelling artistic context. Building attends the inevitable conclusion that in the use design, siting, construction techniques, and use of earth are solutions to issues that even the afflu are problems solved differently by different ent may find useful. This essay looks at one case, groups, always dictated by physical conditions not yet a history, that is seeking in a mult-disci and cultural mandates. The manner in which plinary way to answer a modern need through those problems are addressed comprise part of a
CRM No 6—1999 27 particular cultures local knowledge; the tradi Among the indigenous peoples of the tional technologies offer a solution, with both southwestern United States are those who have technical and artistic components, to a physical been referred to as the "first penthouse dwellers or social need. of America." The Pueblo communities of New In a world of shrinking space, ubiquitous Mexico and Arizona have long been renowned manufactured goods, and environmental degra for their use of local natural resources in the con dation, all of which threaten cultural survival, the struction of large, sustainable, and highly effi social sciences, especially anthropology and its cient communal house blocks. attendant disciplines, are working to redefine and Early photos capture the beauty of the attach day-to-day relevance to their practices. puebloan forms and hint at the adaptive Anthropology, ethnology, and archeology are approach to the environment. Later studies, taught and practiced differently today than they notably at Acoma in the 1970s, verify that the were just a generation ago. Implicit in their evo orientation and massing of the house blocks took lution is the acknowledgment that it is no longer maximal advantage of solar exposure, allowed sufficient to observe and report; objectivity, so minimal exposure to prevailing westerly winter long the bastion of anthropology's scientific pedi and spring winds, and took a cognizant approach gree, is now being complimented with a subjec to the conservation of heat. The precise align tive aspiration to put the lessons of the past ment of the facades a few degrees east of south, actively to work. and the stepped configuration of up to three sto Just as the social sciences are working to re ries capping the coolest, northernmost rooms create themselves, architecture (the most ubiqui were successful answers to environmental chal tous of the plastic arts) is undergoing one of its lenges. No modern day engineer could contrive a regular self-examinations. For many of us the better solution using the materials of the time. very term "architecture" marks a discipline that is Cornerstones Community Partnerships, a anything but disciplined, whose history is punc not-for-profit organization, has for the past 13 tuated by alternating moods of depressed stagna years been assisting rural communities restore tion and brilliant creative explosion, constantly their crumbling earthen religious structures, re-assessing itself and changing to either accom including churches, kivas, and clan houses, and modate or flagrantly ignore the exigencies of the revive the traditional technologies that led to moment. Today, led by theorist-practitioners their rise in the first place. Among the 150-plus such as Vittorio Gregotti, cognizant architects are communities to whom Cornerstones has pro re-examining their roles as both conservationists vided technical assistance, training, and long- and innovators. Gregotti suggests that both com term support have been the pueblo communities ponents of architecture, innovation and conserva of Hopi and Zuni. tion, have been in a state of "advanced medioc At Zuni, where Cornerstones maintained a rity" having intellectually retreated to a safe posi youth training program in architectural conserva tion characterized by an abhorrence of change. tion over a period of six years, concern for find Architects, argues Gregotti, can shake the impasse ing an alternative to the standard Housing and only if they are as attentive to constituencies as to Urban Development (HUD) plans, characterized clients, responding as interestedly to craftsmen by frame-stucco row houses outside the confines and communities as to engineers and planners. of the pueblo itself, became an issue of particular In a wonderful and hopeful nuance, anthro interest. Former governor Robert M. Lewis who, pology and architecture are thus learning to during a nearly 30-year tenure brought running understand and to use one another's lessons in an water, electricity, and paved roads to Zuni, eminently suitable context. This happy circum acknowledged regret that he had allowed HUD stance is nowhere more clearly illustrated than in to follow the western pattern of housing in a dis the currently evolving approach to the conserva tinctly non-western setting. The clan system as tion of earthen vernacular traditions. This well as the long-established order in which includes the use of local knowledge in solving the extended families accreted rooms to their homes ever-present quandary (as long as the world's as needed, was nearly destroyed by the removal of population continues to grow) of providing both from the Middle Village into a setting affordable yet culturally appropriate housing for where both clans and families were arbitrarily communities. mixed.
28 CRN! No 6—1999 During the last years of his administration A cost analysis of the model home demon Governor Lewis sought ways to reverse that strates that the pressed block is in fact competi trend. Among his thoughts was the idea of using tive even with frame modular homes. Because a local resources, both human and natural, in the pressed block comes out of the machine and is building of homes. Although Governor Lewis did laid immediately in the wall, transport and han not live to see his thoughts materialize, the valid dling are eliminated and the cost per unit, laid in ity of the concept is about to be realized at neigh the wall comes to roughly 3 cents as opposed to a boring Acoma and more distant Santo Domingo. cast block at about $1.50. In the end, the earthen In 1997 the tribal governments in both structure will cost approximately 90 cents per pueblos approached Cornerstones for advice and square foot more than a manufactured unit assistance for the conservation of some of their brought in from Albuquerque. And, of immense older homes and for the building of new ones. At importance, this house will be built by a local Acoma the local housing authority under the labor force. Art and the social sciences are com directorship of Raymond Concho is planning to ing together very nicely in this project. build a model earthen HUD-financed home in Those of us who advocate the use of earth 1999. If all goes well, this could be the harbinger as a building material, who see not just utility but of massive change in the way Indian housing is beauty in homes constructed thus, are heartened approached, and the ramifications for low- by the visionary approach to their housing issues income housing generally are immense. that the Pueblo of Acoma Housing Authority has With technical assistance from taken. A great many communities will be watch Cornerstones, and with critical services being ing closely as this project unfolds. If it works, it provided by the University of Pennsylvania, will bring jobs to the locally unemployed, reduce Graduate School of Fine Arts, Department of the import of high-energy-embodied materials Architecture, the Pueblo of Acoma Housing such as Portland cement, and will result in homes Authority has been provided with designs for a that are efficient, beautiful, and sustainable. And subdivision layout as well as plans for solar- in the process of building the houses, local heated earthen dwellings. These designs came knowledge will be passed along through mentor- about through a graduate studio conducted by ship programs that are part of the training. Tony Atkin at the University of Pennsylvania in Strong incentives, indeed. which students worked with tribal officials and Loren Eisley commented that "if there is potential homeowners to derive plans compatible magic on this planet, it is contained in water.* A with the Acoma lifestyle. The plans also reflect paleontologist, he was completely in awe of the the features and forms of the early houseblocks. diversity of life made possible by the presence of Construction of the 2,400-square-foot water on Earth. If I may borrow the thought duplex will be predominantly of pressed earthen from Professor Eisley, I would turn it to the use block. Following the lead set by Santa Fe Habitat of builders, both vernacular and professional, and for Humanity architect Alfred von Bachmayr, the say that if there is magic in their craft, it is con design includes double-width cavity-walls effec tained in earth. tively eliminating the need for insulation. Earthen plasters on the outside and lime plasters Note within provide sympathetic finishes easily and Loren Eisley, The Immense Journey (New York: Time inexpensively maintained by the homeowner. Inc., 1962), p.10. Further reading: Brick and earthen floors, vigas, and fireplaces Gregotti, Vittorio. Inside Architecture. Cambridge and downstairs are among the features, and a well- London: The MIT Press, 1996. insulated roof over the second story assures that Scully, Vincent. Pueblo; Mountain, Village, Dance. New heat is conserved. Although it would be finan York: The Viking Press, 1975. cially impossible to build homes with such amenities using traditionally cast adobe bricks, Ed Crocker, Crocker Ltd., is an architectural conservator. the use of pressed blocks makes the project He is a former technical director for Cornerstones, Santa affordable. Fe, New Mexico.
CRM No 6—1999 29 Richard Pieper Earthen Architecture in the Northern United States European Traditions in Earthen Construction
n the United States, the use of earth German-Russian builders in the mid-19th cen for building is most frequently associ tury in settlements as far east as western New ated with Hispano-American tradi York utilized mud brick for nogging within tim tions of adobe construction in the ber frames. In all of these systems earth was a sig SouthwestI. There is also, however, in the north nificant component of the wall system, but the ern United States a significant tradition of structure was basically wood. However, a number earthen wall construction that is related to tech of contemporaneous traditions in the Northeast niques of northern European immigrants. feature buildings constructed with load bearing Early construction in the northeast by earthen walls, similar to Southwestern adobes. Dutch settlers exploited the insulative properties Perhaps the earliest method of load bearing of earth used as infill in wood frame structures. earthen wall construction practiced in the north "Wattle and daub" typically utilized small riven ern United States was "cob" walling. Cob walling, wood laths secured in stud cavities with wood a traditional English technique of monolithic strips or shallow mortises, and a mud and straw earthen wall construction, used a mixture of Greek Revival mixture to fill the frame openings of both inte moistened earth and straw. The mud and straw style mud brick residence in rior and exterior walls. Exterior wall surfaces were mixture could be laid as walls with or without the Bath, New York. typically boarded or sided with nailed lath and use of wooden form work. In New York State, Nearly all of New wood shingles, but interior walls were usually the earliest documented extant earthen structures York State's mud brick buildings plastered and whitewashed directly on the surface are two cob walled residences. The Lawrence were constructed of the nogging. Wattle and daub nogging is com Johnston House (1832 or 1833) and the William between 1840 mon in Dutch tradition houses in areas of Dutch Gorse House (1836) are located a few miles apart and 1851 and reflect the Greek settlement (the Hudson Valley and Northern in Penfield, Monroe County, near Rochester. Revival, Gothic New Jersey) of the 17th and 18th centuries. In While the Johnston House's wall construction is Revival, and the 19th century, traditional Ukranian construc now obscured by clapboard siding, several Italianate styles popular at that tion in North Dakota used a similar, if somewhat exposed areas in the interior show that the mix time. Photo by cruder, system of lath nailed on earthfast poles ture of mud and straw was placed within wooden the author. and filled with mud for dwelling construction. wall forms in layers about six inches deep. An account of the construction of the Gorse House re-published in a Penfield history states: A pen was built on the ground and clay drawn from a nearby creek bed spread over the ground to a depth of about a foot. On this, cut straw was spread to a depth of three to four inches. Oxen were driven around and around inside the pen to thoroughly mix the ingredients. Plank forms about a foot high were set up on the wall foundations and filled with the clay mixture. As soon as the clay and straw had dried sufficiently to be self-sup porting, the forms were raised and another course poured. Floor joists were laid across the walls and another layer poured on top, thus embedding the joists in the wall. When com pleted a year later, the house was given a thin
30 CRM No 6—1999 plaster coat of clay and the interior walls were coolest in summer of any buildings of their size I plastered and kept white-washed.* ever knew." An account of similar cob walled structures Writing in The American Farmer in 1824, a was given by author Stephen W. Johnson, who in Dr. William W. Anderson of Stateborough, 1806 in New Brunswick, New Jersey, published South Carolina, recounted his experimentation Rural Economy: Containing a Treatise on Pisé with rammed earth construction, which had Construction. Johnson describes several mud begun with the construction of a 10' x 14' dairy walled buildings near Trenton, New Jersey, with in April 1821. Pleased with the results, Anderson "walls ... twenty inches thick, built of mud and constructed a rammed earth dwelling for house straw, as the English ones are done." As its title servants in July 1823. Anderson also appears to suggests, Johnson's book was actually primarily a have used Johnson's book as his instruction man study oí pisé, or rammed earth construction. ual, and went on to construct five other struc Johnson's interest in rammed earth construction tures of rammed earth on his plantation. The was sparked by the the seminal writings of plantation's buildings were listed in the National Francois Cointeraux, French agriculturalist and Register of Historic Places in 1972, and along architect, whose publication of a series of cahiers with a local church constructed in the 1850s are on rammed earth construction in 1791 started a believed to be the largest concentration of his chain of translations and adaptations that reached toric rammed earth structures in the eastern the United States in the early-19th century. United States. Cointeraux was not the first Frenchman to write About the same time that Anderson was about rammed earth construction, which had completing his complex of rammed earth build been chronicled by others reporting on pisé con ings in South Carolina, and Gorse and Johnston struction then common in the areas around were experimenting with cob wall construction Lyons. Cointeraux' reports were backed by con outside of Rochester, English architect and horti siderable personal experimentation, however, and culturist John Claudius Loudon was publishing he pursued the dissemination of his techniques his influential Encyclopedia of Cottage, Farm, and with a proselytic zeal that soon attracted the Villa Architecture (1833), a compendium of attention of like-minded architects in Great designs and prescriptions for construction that Britain. By 1797, Cointeraux' first and second contained no fewer than 29 illustrations for cot cahiers on pisé construction were translated into tages that Loudon proposed were appropriate for English by noted English architect Henry earthen construction. Loudon noted Cointeraux' Holland and published with new illustrative pisé experiments but also quoted the report of fel plates in the Communications of the Board of low Englishman John Denson whose Peasant's Agriculture of Great Britain. Holland's transla Voice reported on the use of "clay lumps" or tion was reworked and plagiarized in America by unburnt brick, for the construction of cottages in Stephen Johnson. Johnson's book was illustrated Cambrigeshire. English author John McCann has with plates resembling Cointeraux' original presented convincing evidence that this tech engravings, and it included sections on such dis nique was developed in East Anglia at the end of parate topics as road building and viticulture. the 18th century, and was not, as was earlier Johnson's book, and Holland's translation, which thought, an ancient traditional English construc was republished in the agricultural journal The tion method. Whatever its origins, and whether American Farmer in 1821, sparked in the Mid- prompted by Loudon's encyclopedia or simply Atlantic and southeastern United States a series immigrant English technique, buildings were of experiments in pisé construction that were being constructed of unfired mud brick near chronicled in agricultural journals in the first Toronto, Canada, as early as 1836. By September four decades of the 19th century. Responding to 1842, the Canadian publication, The Church, inquiries from the publisher of The American was reporting of the new Hurontario Church, Farmer, Virginia planter John Cocke of Bremo "the new church is to be built of mud (or Plantation near New Canton wrote of his con unburnt) brick, which in the opinion of the best struction of two small pisé buildings during the informed architects, is the material of all others summer of 1816. Cocke indicated that he had the fittest for the building with in this province." followed the instructions in Johnson's book, and In February 1843, The British- American praised the buildings "which have stood perfectly, Cultivator, a Toronto agricultural journal, affording the warmest shelter in winter and the
CRMN06—1999 31 ing that unburnt brick would well serve those of modest means settling on the untimbered prairies of the then far west. Ellsworth's intentions notwithstanding, the vogue spread to other areas. By 1855, more than 40 mud brick structures, most not nearly so sim ple as Ellsworth's prairie cottage, dotted a nine- county area in New York that spanned half the state. While the New York State examples have perhaps been documented best, similar buildings have been identified in Pennsylvania, Michigan, and Nebraska, and no doubt many more are known locally in adjacent states. In his 1967 study of historic construction technology in cen tral Canada, Building with Wood, author John This Gothic reported that "houses, properly constructed (of Rempel also confirms the popularity of the tech Revival style resi unburnt brick) are warmer, more durable, and nique in neighboring York County, Ontario. dence in also cheaper than frame, and are destined to take Geneva, Ontario In New York State, Ontario County was County, New the place of the log shanty, as well as the more quite certainly the center of this mud brick York, is typical of expensive wooden walls." vogue; census records indicate that at least 22 earthen buildings Unburnt brick construction was being constructed in mud brick structures had been built in the Geneva. Over 20 championed at the same time in the United county by 1855, far more than in any other. At mud brick build States by U.S. Commissioner of Patents Henry least 14 mud brick buildings were constructed in ings had been Leavitt Ellsworth. Son of U.S. Supreme Court consructed in the village of Geneva alone. One contemporary Ontario County Chief Justice Oliver Ellsworth, and brother of account reveals that the initial use of unburnt by 1855. Photo Connecticut Governor William Ellsworth, H. L. brick in Geneva antedated Ellsworth's first pub by the author. Ellsworth chronicled advances in agricultural sci lished report, however, and the discrepancy ence in his patent office reports of the 1830s and between the brick sizes recommended by 1840s. Ellsworth's reports of 1842, 1843, and Ellsworth (12" x 7" x 5" and 12" x 6" x 6") and 1844 reprinted excerpts about unfired brick from that of the majority of mud brick buildings in Loudon's encyclopedia and The British-American Geneva (15" x 12" x 6") suggests that immigrant Cultivator, and reported on Ellsworth's own suc English or Canadian practice may have served as cessful experiments with mud brick construction a model for the earliest Geneva construction. It is in Washington, DC, and Grand Prairie, Indiana, apparent also that Geneva mud brick construc that had begun in 1842. Ellsworth's influential tion influenced others wishing to experiment reports were widely excerpted and reprinted in with this construction technique; the 15 " x 12" x agricultural journals such as The Cultivator 6" Geneva brick size can be found in buildings in (Albany, N.Y.), and The Genesee Farmer Bath, Steuben County, and Interlaken, Seneca (Rochester, N.Y.). The New York Tribune, which County. published an excerpt about unburnt brick con Although the architectural treatises of the struction soon after the first report's publication period were not silent on the subject of unburnt in February 1843, separately reprinted a sizable brick, few dealt with the mode at length or in portion of the report in pamphlet form under the adequate detail to assist a would-be builder. One title Useful Works for the People No. II. notable exception was The Architect (1849), a Ellsworth's motivation to experiment with journal published by the New York City architect this novel form of construction was apparent. William Ranlett. Ranlett's book may have been Already a landowner in the Wabash Valley of the first eastern publication to use the Spanish Indiana, Ellsworth was to become an agent for term "adobe" for the construction technique that federal lands in the area following his departure previously had been identified as "unburnt from the Patent Bureau in 1845. An illustration brick," "sundried brick," "mud brick," or even of Ellsworth's proposed "prairie cottage" in the "Egyptian brick." While Ranlett devoted only 1844 report leaves no doubt that, in spite of his two pages and three designs to adobe construc rather large (18' x 54') experimental brick struc tion, he gave detailed prescriptions for construc- ture in Washington, DC, Ellsworth was propos
M CRM No 6—1999 tion and undoubtedly his copiously illustrated Mode of Building," was by February 1855 stat pattern book lent a certain cachet to the novel ing, "... this mode of building is falling into dis building mode that had prompted so much pub use, doubtless for some substantial reasons, licity in the previous five years. It appears that among which is probably the difficulty of having Ranlett's work inspired the construction of what every part done well, and especially the great dif was by far New York's largest documented ficulty of securing good cement, so essential to earthen building, the Judge Samuel Ludlow success." Some innovative builders, inspired by Residence in Oswego. Under construction in Orson Fowler's The Octagon House, A Home for 1851, the Ludlow residence when complete had a All turned instead to what was to become the major facade 70 feet long, two 2-1/2-story hip- next heralded replacement for fired brick roofed ells 45 feet long, and an adobe tower with masonry—the gravel wall. As early as February a wood frame top that rose 40 feet. Until it was 1846 one correspondent to The Cultivator offered demolished recently, Ludlow's residence served as a comparison of the two technologies: "I read in a convent for a neighboring Catholic high school. Ellsworth's report of last winter, the manner of building cheap houses of unburnt brick; but I think they have an improvement in Wisconsin over all others. The material consists of gravel and lime—one-eighth part lime, and the balance of coarse sand and any kind of gravel or small stones, mixed so as to make a mortar that will 'set' so hard as to stand well." Few stylistic generalizations can be made about northern mud brick buildings. The buid- ings identified to date reflect then-current Greek Revival, Gothic Revival, and Italianate styles. Similarly, the buildings cannot be said to have been favored by one socioeconomic group; the 1855 census records values for the buildings in New York State ranging from $100 to $15,000. Today most remaining examples are in sound condition and all are occupied. Many retain their original exterior stucco finishes, although some When it was By the early 1850s, the mud brick vogue have long been re-sided with wood clapboard, demolished in was slowing considerably, no doubt prompted in aluminum, or brick, and hide their identity from the 1970s, this board-and-bat- part by the difficulty of preventing exterior the casual observer. Quite certainly others remain ten sided build stucco finishes from failing. The stucco problem to be found, unlikely relics of an innovative era in ing in Geneva had been mentioned frequently in early accounts, American masonry construction, confirming the was found to be load bearing and prompted at least two New York State claims of adobe's 19th-century proponents about mud brick con builders to include horizontal wooden members the durability of earthen construction in the struction, origi within the walls between alternate layers of brick, harsh climate of the northern United States. nally sided with- wood. Photo by so that the completed masonry building could be David Brumberg. sided with wood. Note Despite the generally glowing tone of the John McAnn "Is Clay-lump a Traditional Building early press, not all later publications treated the Material?" Vernacular Architecture 19 (Vernacular Architecture Group, 1988): 1-16. topic so favorably. In his 1852 book Rural Architecture, Lewis F. Allen indicated "we are Richard Pieper is a principal and Director of Preservation aware that unburnt bricks have been strongly rec forjan Pokorny Associates, a historic preservation archi ommended for house building in America; but tecture firm in New York City, and is an Adjunct from observation we are fully persuaded that they Assistant Professor for the Graduate School of Architecture, are worthless for any permanent structure, and if Planning, and Historic Preservation at Columbia used, will in the end prove a dead loss in their University. Pieper researched the earthen architecture of application." The Cultivator, which in March New York State with the assistance of a grant from the New York State Council on the Arts in 1984. 1847 had published an article about mud brick construction entitled "The Cheapest and Best
CRM No 6—1999 33 Edna E. Kimbro California's Historic Earthen Architecture Arquitectura Histórica de Tierra en California
alifornia's historie earthern archi as tradiciones de la arquitectura tectural traditions differ in sev histórica de tierra en California eral respects from those in se diferencian en varios aspectos Arizona and New Mexico. In the de la arquitectura de Arizona y last quarteCr of the 18th century, missionaries and NuevoL México. En el último cuarto del siglo military personnel endeavored to imitate the XVIII los misioneros y militares intentaron designs of churches with which they were familiar reproducir los diseños de iglesias que les eran in the drier climates of the Borderlands. conocidos de los climas más secos de las fron However, it soon became apparent that the teras. Sin embargo, muy pronto quedó claro azoteas, or relatively flat-roofed construction with que las azoteas o techos relativamente planos canales, or roof drains, were not appropriate con canales de drenaje no eran adecuados para along the coast of California where the missions el clima de la costa de California donde se were erected. Around 1780 to 1781 (depending erigían las misiones. Alrededor de 1780 o 1781 upon the source consulted), barrel roof tiles were (dependiendo de la fuente consultada) en la first fired at Mission San Antonio de Padua, and Misión de San Antonio de Padua se cocieron low-pitched tile roofs began to replace the leaky las primeras tejas cóncavas (tipo árabe) y se masonry azoteas. comenzó a reemplazar las azoteas de albañilería The fact that most of the missions, if not llenas de goteras por techos de poca pendiente all, were located in seismic zone four, along the con tejas coast where the risk of earthquakes is highest, Que la mayoría, sino todas las misiones certainly influenced the design of mission build estuvieran ubicadas en la zona sísmica cuatro a ings. With experience as their teacher, the design lo largo de la costa, donde es mayor el riesgo de ers learned that stout walls with an aspect ratio of terremotos, ciertamente influyó en el diseño de five to one or lower could withstand severe las construcciones de las misiones. Los dis ground shaking better than tall, thin walls. Thus, eñadores aprendieron por la dura experiencia most of the surviving mission churches have walls que los muros gruesos con una proporción of five or more feet in thickness. dimensional de cinco a uno o inferior soporta Rising damp, ever a threat to earthen ban mejor los fuertes movimientos de tierra que masonry, was also a problem in California. This los muros altos y delgados. Así, la mayoría de was addressed by extending stone foundation las iglesias de misiones que han sobrevivido stem walls above grade some three to five feet to tienen muros de 5 o más pies de grosor. counteract the propensity of adobe to wick La humedad ascendente que es la ame groundwater into the walls. Some of the mission naza permanente para la albañilería de tierra churches were constructed entirely of stone, a también era un problema en California. La material considered more noble and definitely solución encontrada fue extender los muros de more lasting than earthen materials. Sometimes fundación de piedra unos tres o cinco pies only the facade of the church was constructed of sobre el nivel, para contrarrestar la propensión stone, which had the advantage of greater del adobe a desaguar el agua del subsuelo en los strength when damp but the disadvantage of muros. Algunas iglesias de misiones se hicieron
34 CRM No 6—1999 being difficult totalmente de piedra, un material considerado to work. With más noble y definitivamente más duradero que the importation los materiales de tierra. En otros casos, sola of skilled mas mente se construyó con piedra la fachada de la ter masons iglesia, lo que tiene la ventaja de ser más from Mexico in resistente a la humedad pero difícil de trabajar. the 1790s, Los expertos maestros canteros traídos desde stone mission México en los años 1790 hicieron posible por churches were breve tiempo construir de iglesias de piedra en viable for a las misiones. short time. Cuando examinaban los lugares más In survey apropiados para establecer nuevas misiones, los ing appropriate fundadores buscaban siempre que existiera una sites for the buena provisión de madera y cal y un buen establishment contingente de indígenas como potenciales of new mis conversos. La madera era necesaria para la con sions, the strucción de techumbres y andamios, y la cal founders sought interesaba porque protege los muros de la those with good erosión superficial del agua. Como se creía que wood and lime la cal era un buen desinfectante, se incentivaba sources as well el encalado o pintura con cal que evitaba la as an abun propagación de enfermedades infecciosas como dance of Native la viruela. Los muros de adobe se estriaban y American calafateaban en líneas, como un achurado potential con cruzado que le daba más adherencia al revoque verts. Wood de cal. La superficie resultante se decoraba con Arcaded corri was needed for the construction of roofs and scaf motivos tradicionales sobre un friso de tres a dor, Mission folding, while lime was sought to protect walls cinco pies que recorría la base de los muros. Santa Inés, from surface erosion by water. Because lime was Solvang, Estos motivos se aplicaban usando pigmentos California. thought to be an effective disinfectant, lime- or importados de México; entre otros orígenes de whitewashing was encouraged to prevent the Corredor con los pigmentos estaba la hematita local. bóveda con spread of infectious diseases such as small pox. Muchos establecimientos misioneros tinua, Misión Adobe walls were both chinked and scored or de California presentan un largo corredor Santa Inés, incised with lines in a cross hatch manner to pro Solvang, abovedado que recorre el convento o edificios vide mechanical keys for the lime rendering. The California. anexos adyacentes a la iglesia. Las arcadas de resultant surface was often decorated with tradi albañilería se construían fundamentalmente tional motifs above a three- to five-foot dado at con ladrillos cocidos, unos ladrillos planos y the base of the walls. These motifs were applied delgados similares a las baldosas coloradas, pero using pigments imported from Mexico. Other menos cocidos. También se usaban ladrillos pigment sources include locally available para dar forma a los detalles arquitectónicos en hematite. la fachada de la iglesia. Los corredores de Several of the mission establishments of misiones menos sofisticadas se construían con California featured a long corridor that took the postes de madera o columnas de piedra que form of an arcade along the convento, or associ sostenían los tejados. Al igual que los portales ated buildings, adjacent to the church. Typically en la arquitectura de tierra de Nuevo México, the masonry arches were constructed of burned los corredores abovedados y los más simples ladrillos, or thin flat bricks that are similar to protegían de la lluvia y el sol, ofreciendo tam quarry tiles but less well fired. Ladrillos were also bién un pavimento seco para transitar. used to fashion architectural details for the facade La arquitectura residencial de los pueblos of the church. The corridors of less elaborate mis y presidios (fuertes militares) no se diferenciaba sions were constructed with wooden posts or mucho de las áreas residenciales de las misiones, stone piers supporting the tiled roofs. en cuanto a las viviendas para los soldados y Comparable to the portales of New Mexican neófitos. Normalmente las construcciones de
CRM No 6—1999 35 earthen architecture, both arcaded and simpler adobe seguían un plan lineal, con habitaciones corridors provided protection from the rain and comunicadas entre sí a lo largo de un eje y sun as well as a dry pavement to walk upon. corredores por delante y atrás. En los presidios The vernacular residential architecture of y en torno a las plazas centrales de los pueblos the pueblos and presidios was not unlike that of era común encontrar construcciones con pare the residential portions of the missions, the hous des medianeras y corredores continuos, simi ing provided to the soldiers and the converted lares a los portales continuos de Santa Fe, neophytes. Typically, the adobe buildings were Nuevo México. Se acostumbraba cerrar parte linear in plan with rooms opening into one de los corredores traseros para crear cocinas o another along an axis with corridors along the más habitaciones. front and rear. In the presidios and around the (Un hecho poco conocido es que durante central plazas of the pueblos, party wall construc su período hispánico, California tuvo su propia tion was common with continuous corridors sim versión de luminarias o farolitas: En las memo ilar to the continuous portales of Santa Fe, New rias del Gobernador Juan Bautista Alvarado se Mexico. Portions of the rear corridors were fre relata que en las noches de ocasiones especiales quently enclosed for use as kitchens or extra los techos de los corredores de los presidios se rooms. (A little known fact is that during its cubrían con lamparillas cerámicas de aceite). Hispanic period California had its own version of En la década de 1830, cuando comenzó la luminarias/farolitas: According to the reminis secularización de las misiones, se construyeron cences of Governor Juan Bautista Alvarado, on edificios de dos pisos en adobe, manteniendo Castro Adobe, the evening of special occasions, the roofs of the los corredores como rasgo característico. Las rural rancho presidio corridors were lined with small pottery casas aisladas tenían corredores parecidos a las adobe in oil lamps.) "Monterey galerías de la arquitectura del estilo Greek style," Starting in the 1830s, around the time of Revival, en varias elevaciones, en tanto los bal Watsonville, the secularization of the missions, two-story cones voladizos eran muy comunes en las con California. adobe buildings were constructed, again with strucciones urbanas con muros divisorios. Adobe Castro, corridors as a typical feature. Free-standing Ambos rasgos son distintivos del estilo arquitec rancho rural en homes had corridors resembling the verandas of adobe, del tónico Monterrey, llamado así por la capital estilo Greek Revival architecture on several elevations española y mexicana de California. Monterrey, en while cantilevered balconies were common on Los historiadores de la arquitectura han Watsonville, urban buildings with party walls. Both features California. discutido por años sobre los orígenes del estilo came to characterize Monterey style architecture, Monterrey. Algunos lo atribuyen a la influencia named for the de un sólo edificio construido en 1832, la Spanish and Mexican notable casa de dos pisos de Thomas O. Larkin, capital of California. Cónsul General de EE.UU. En estos últimos Architectural años se ha sabido que tanto el Gobernador historians have long Alvarado, oriundo de California y el Cónsul argued about the ori Larkin, inmigrante de Nueva Inglaterra con gins of the Monterey struyeron casas de dos pisos en 1832; ambas style, some attribut incorporaron elementos de arquitectura Greek ing it to the influence Revival, un estilo arquitectónico muy difun of a single building dido de inspiración clásica. El estilo Monterrey begun in 1832, the se asemeja al estilo Territorial de Nuevo México prominent two-story pero con tejados de dos aguas de tejuelas finas home of U.S. Consul partidas a mano llamadas tejamaniles en lugar General Thomas O. de los techos planos. Las características Larkin. In recent comunes a las construcciones de estilo years it has become Monterrey son las ventanas de guillotina, known that both tablones de techo machihembrados con Governor Alvarado, a molduras, vigas y marcos de ventanas, puertas Californio, and de seis paneles, balaustradas torneadas y pilares Consul Larkin, a de arranque, aleros cerrados, persianas o New England immi- celosías, tragaluces y vidrios laterales en la
36 CRM No 6—1999 Alvarado Adobe, grant, erected two-story resi Monterey, dences in 1832, both of which California, with clapboard siding incorporated features of Greek and greek revival Revival architecture, a wide corridor. spread and classically derived Adobe architectural style. The Monterey Alvarado en style is not unlike the Territorial Monterrey, style of New Mexico, but with California, con entablado exte gabled, or hipped, roofs of thin rior y corredor hand split shingles, or en estilo nuevo tejamaniles, instead of flat roofs. greco. Features common to buildings constructed in the Monterey style were six-over-six window sash windows, beaded tongue and grooved ceiling boards, joists entrada y una galeria con columnas and window casings, six-panel doors, turned achaflanadas. Era usual encontrar casas de balusters and newel posts, boxed eave returns, simetría bilateral y recibidores centrales con shutters or blinds, side lights and transoms at the escaleras, pero también eran comunes las casas entry, and verandas with beaded or chamfered tradicionales en forma de U que rodean patios posts. Bilateral symmetry and central stair halls centrales y de plano cuadrangular (semejantes a were not unusual, but traditional U-shaped la cuadrícula de las misiones, pero más homes surrounding courtyards and quadrangular pequeñas). plans (similar to the mission quadrangles, but En general, la parte sur del estado demoró smaller) were also common. en adoptar las nuevas características arquitec Generally the southern part of the state was tónicas, reflejo tal vez de las costumbres rurales somewhat slower to adopt new architectural fea más conservadoras de esta región. En el sur, las tures, perhaps reflecting the more conservative ventanas con bisagras similares a las usadas en rural attitudes of this region. In the south, case las misiones eran más comunes que las ventanas ment windows similar to those used in the mis guillotina deslizantes de seis por seis, y las casas sions were customary rather than the six-over-six de adobe de dos pisos aparecieron mucho sliding sash and two-story adobe homes, which después. Las construcciones de adobe de techo were developed later. Flat-roofed adobe buildings plano recubierto con alquitrán o brea, material with tar or brea (naturally occurring asphalt asfáltico natural, continuaron usándose en el material) roof covering also continued to be used sur, mucho después que Monterrey adoptara las in the south long after Monterey adopted shin tejuelas producidas en la vecina cordillera de gles produced in the nearby Santa Cruz Santa Cruz. Los techos se recubrían con Mountains. The roofs were tarred with brea or alquitrán o con tejas sobre una armadura con tiled over a roof system constructed of wooden struida con envigado de madera, latitas o ramas vigas, or round wooden beams, with latitas, or finas de sauce (atadas con tiras de cuero sin cur thin branches, of willow (lashed with rawhide in tir en las primeras épocas) que se calafateaba y the early days), that was chinked and covered cubría con una capa de barro, método similar al with a coating of mud, a method similar to early usado en las primitivas construcciones de mission roof construction. In later years, south of techos en las misiones. Años más tarde se puede Santa Barbara it was possible to find brea roofs encontrar al sur de Santa Bárbara los techos installed over the Greek Revival styles roof sys alquitranados instalados sobre armaduras de tems characterized by beaded joists and beaded estilo Greek Revival, caracterizados por las vigas tongue and grooved sheathing. In Santa de techo achaflanadas y entablado machihem Barabara, however, shingles replaced roof tiles. brado con molduras. En Santa Bárbara las Tile roofs were used in communities where tejuelas tipo tejamaniles reemplazan a las tejas. mission and presidio buildings robbed of their Los techos de teja se usaron después de la roof tiles following the decline of the missions decadencia de las misiones y presidios, en and the presidios after the end of the Mexican comunidades en las cuales las tejas eran robadas
CRM No 6—1999 37 War of Independence de los techos de esas misiones y presidios, al tér in 1821. However, mino de la Guerra de Independencia de México the number of tile en 1821. Sin embargo, el número de techos de roofs diminished over tejas había ido disminuyendo paulatinamente time as their produc con el cese de producción de tejas luego que los tion ceased upon the indígenas de la misión eran liberados. freeing of the mission La desaparición de la arquitectura de Indians. tierra en California en las últimas décadas del The demise of siglo XIX se debe en parte a la influencia de los earthen architecture norteamericanos del Este (comenzando con la in California in the fiebre del oro), que trajeron consigo el gusto later decades of the por los estilos arquitectónicos de Nueva 19th century is due in Inglaterra y miraban en menos estas edifica part to the influx of ciones de ladrillos de barro de los californianos Americans (beginning a quienes despreciaban. La vulnerabilidad a los with the gold rush), daños causados por terremotos de estas con who brought with strucciones de albañilería no reforzada fue un "Larkin House," them a preference for New England architectural factor que contribuyó a la impopularidad del Monterey, styles and scorned the mud brick buildings of the California, adobe como material de construcción, pero esto Monterey-style native Californians, or Californios, they despised. no pareció impedir la construcción con ladrillos icon with broad The vulnerability of unreinforced masonry build refractarios. Además, al correr de los años fue overhanging ings to earthquake damage was a contributing corridors. menguando el número de indígenas de las factor to the unpopularity of adobe as a building antiguas misiones que dominaban los métodos Casa Larkin en material, but this did not seem to deter construc de construcción en adobe y las nuevas genera Monterrey, tion in fired brick. In addition, as time went on, California, sím• ciones de californianos no eran capaces de bolo del estilo the number of former mission Indians skilled in reparar los edificios de adobe dañados. Monterrey, con adobe construction methods dwindled, and new Actualmente, la escasez de construcciones amplios corre generations of Californians were unable to repair dores col históricas de adobe en California (quedan unas gantes. damaged adobe buildings. 350 estructuras de este tipo, incluyendo las Today, the scarcity of historic adobe build misiones) puede atribuirse al agresivo desarrollo ings in California (there remain but about 350 que amenaza a las construcciones del siglo XIX such structures, including the missions) can be y los daños por terremotos. La tercera amenaza attributed to rampant development, which gener histórica, la indiferencia social ante las mani ally threatens 19th-century buildings, and to festaciones culturales de una población con damage by earthquakes. The third historic threat, quistada es menos importante hoy de lo que societal indifference to the cultural manifesta fuera en el siglo XIX. A medida que vaya cam tions of a vanquished population, is less a factor biando la estructura demográfica del estado y today than it was in the 19th century. As the que la mayoría de la población sea de habla state's demographics change, and as the majority española, se puede esperar que las casas y of the population becomes Spanish speaking, it is misiones históricas de adobe que aún quedan hoped that the remaining historic adobe homes en el estado serán más queridas y mejor conser and missions of the state will be better appreci vadas. El naciente interés por la arquitectura de ated and conserved. The nascent interest in tierra en California, especialmente de tierra earthen architecture, specifically rammed earth, apisonada, es alentador. in California is encouraging. Edna E. Kimbro es la presidenta de la compañía Edna Edna E. Kimbro is Principal, Edna E. Kimbro E. Kimbro, Consultante de Investigation Histórica, Historical: Architectural: Conservation Research Arquitectónica y de Conservación, en Watsonville, Consultant, Watsonville, California. She is registered pro California. Ella es una historiadora profesional reg fessional historian No. 543 in California and ICCROM istrada con licensia no. 543 en California y entrenada trained architectural conservator ARC-89. en ICCROM como conservadora arquitectónica no. ARC-89. Photos courtesy the author. Fotos cortesía del autor.
38 CRM No 6—1999 Anthony Crosby Earthquakes and Adobes Effects and Systems for Intervention Terremotos y Adobes Efectos y Sistemas de Intervención
n 1811, a series of three major earth n 1811 una serie de tres grandes quakes, estimated to have registered terremotos que pudieron haber between 8.4 and 8.7 on the Richter registrado entre 8,4 y 8,7 en la scale, rocked the area of New Madrid, escala de Richter sacudieron la MissouriI. Chimneys fell from buildings as far regiónE de New Madrid, Missouri. Cayeron las away as Georgia and South Carolina, and the chimeneas de viviendas en regiones tan alejadas effects were felt 1,100 miles away in Boston. Few como Georgia y Carolina del Sur y sus efectos deaths resulted because the area was so sparsely se hicieron sentir a 1.100 millas de distancia, en populated and because the buildings, most of Boston. No hubo demasiadas muertes porque which were log cabins, were relatively elastic. The la región estaba apenas poblada y las construc 1960 earthquake in Agadir, Morocco, with a ciones eran más que nada cabanas de troncos magnitude of only 5-8 destroyed the entire city relativamente elásticas. El terremoto de Agadir, and killed 12,000; in this case the epicenter of Marruecos de 1960, con una magnitud de sólo the earthquake was within 5 miles of the city cen 5.8 destruyó toda la ciudad y mató a 12.000 ter. Armenia's 1988 earthquake, with a magni personas; en este caso el epicentro del terremoto tude of 6.9 on the Richter scale, resulted in the estaba a cinco millas del centro de la ciudad; en death of more than 25,000 persons. The magni el terremoto de Armenia de 1988, de magnitud tude of the Armenian earthquake was approxi 6.9 en la escala de Richter murieron más de mately 1/30 the magnitude of the New Madrid 25.000 personas. La magnitud del terremoto de event, but because of poor building design (non Armenia fue aproximadamente 1/3 de la mag contiguous reinforced concrete structures with nitud del terremoto de New Madrid, pero precast floor panels) and the buildings' poor con debido al pésimo diseño de las edificaciones dition, many structures failed traumatically. On (estructuras de hormigón armado no contiguas the early morning of January 17, 1994, an earth con paneles de piso vaciados en obra) y el defi quake that registered 6.8 struck the Los Angeles, ciente estado de las construcciones se derrum California, suburb of Northridge. Eleven thou baron dramáticamente muchísimas estructuras. sand residences were damaged and many were Durante la mañana del 17 de Enero de 1994, destroyed, as were 9 highway overpasses and sev un terremoto grado 6,8 sacudió el suburbio de eral larger commercial structures. There was con Northridge en Los Angeles, California. siderable damage to high-rise structures, and 250 Destruyó o causó daños en 11.000 viviendas, gas lines ruptured; it was the costliest natural dis derrumbó nueve pasos superiores de autopistas aster in U.S. history. The Northridge earthquake y grandes edificios comerciales. Edificios de resulted in the greatest loss of and most damage altura sufrieron graves daños y estallaron 250 to California's historic adobe buildings than that cañerías de gas. Fue el desastre natural más cos wrought by any previous earthquake. The relative toso en la historia de los Estados Unidos. El ter severity of these seismic events was dependent on remoto de Northridge generó más daños y many factors, the most important of which were grandes pérdidas en las construcciones históri the actual characteristics of the event and the cas de adobe de California que cualquier otro design and condition of the buildings affected. terremoto anterior. La gravedad relativa de estos eventos sísmicos depende de varios factores, de
CRM No 6—1999 39 The most commonly referred to characteris los cuales los más importantes son las carac tic of an earthquake is its magnitude, the quanti terísticas reales del evento y el diseño y condi tative measurement given by the Richter scale, an ciones de las edificaciones afectadas. index of the amount of energy released. The sec La característica más conocida de un ter ond most familiar measurement of an earthquake remoto es su magnitud o medición cuantitativa is its intensity, indicated by the Modified Mercalli arrojada por la escala de Richter, un índice de la Intensity scale, which is based upon subjective cantidad de energía liberada. La segunda observations of human reaction and structural medición más conocida de un terremoto es su damage. However, describing the severity of an intensidad medida por la escala de Intensidad earthquake is not a simple task. In addition to Mercalli Modificada que se basa en observa the magnitude measured by the Richter scale and ciones subjetivas de la reacción humana y daños the intensity measured by the Modified Mercalli estructurales. Sin embargo, no es tarea fácil scale, other characteristics such as acceleration, describir la gravedad de un terremoto. Además the duration of the event, and the location of the de la magnitud medida por la escala de Richter epicenter are important in assessing the overall y la intensidad medida por la escala de Mercalli severity. Geologic and soil conditions can exacer Modificada, existen otras características como la bate the severity as well, and aftershocks can aceleración, la duración del evento y la ubi destroy buildings that withstood the initial cación del epicentro que son importantes a la ground motion. All of these factors—the magni hora de evaluar la gravedad total. Las condi tude, the intensity, the acceleration, the duration, ciones geológicas y de suelo pueden aumentar and the location—have a huge effect. The la intensidad y las réplicas pueden destruir las ground moves, often quickly and dramatically, edificaciones que habían resistido el primer and features located on the ground surface must movimiento telúrico. Todos estos factores, mag absorb or withstand the motion in some way or nitud, intensidad, aceleración, duración y ubi they will be affected. A structure on the earth cación, producen un efecto terrible. La tierra se moves or vibrates in response to the seismically mueve con gran rapidez y fuerza y los elemen induced ground motion, and structures with dif tos ubicados en la superficie terrestre deben ser ferent properties respond differently. A rigid capaces de alguna forma de absorber o soportar structure will tend to move with the movement el movimiento, o se verán afectados. Una of the ground while a flexible structure will bend. estructura sobre el suelo se mueve o vibra como Structures of mud brick, or of other load bearing respuesta al movimiento superficial inducido earth systems, with thick walls in relationship to por el sismo y las estructuras responden de dis their height, a characteristic of many archeologi- tinta forma según sus propiedades. Una estruc cal monuments, will normally withstand ground tura rígida tenderá a moverse con el motion with little or no damage. An approximate movimiento del suelo, en tanto una estructura wall height-to-thickness ratio of five to one or flexible se pandeará. Las estructuras de ladrillos less is considered stable. Walls of stronger or de barro u otros sistemas de construcciones de more elastic materials can have a much greater tierra que soportan cargas, que tienen muros height-to-thickness ratio and still be stable. Like gruesos en proporción a su altura, característica the severity of the seismic event itself, predicting de muchos monumentos arqueológicos, nor the actual performance of a structure with floor malmente soportarán el movimiento telúrico and roof systems, combinations of thick and thin prácticamente sin dañarse. Una proporción walls, intersecting walls, and walls of different aproximada de alto por ancho en muros igual o heights, is complex. inferior a cinco por uno se considera estable. The primary method used to protect exist Los muros de materiales más resistentes o elásti ing earth structures has been to increase the rigid cos pueden tener una relación alto/ancho ity of the structural system. Often rigidity was mucho mayor y seguir siendo estables. Como achieved with the installation of reinforced con en el caso de la gravedad de un sismo, es com crete bond beams and columns, the installation plejo predecir el comportamiento real de una of which destroyed significant amounts of his estructura que presenta sistemas de piso y toric fabric. Not only were these methods techumbre, muros gruesos y delgados, muros destructive to important values of these historic intersectados y de distintas alturas. structures but they were often prohibitively
40 CRM No 6—1999 El método básico aplicado para la protec ción de las estructuras de tierra existentes ha sido aumentar la rigidez del sistema estrcutural. En ocasiones la rigidez se lograba instalando vigas y columnas de unión de hormigón armado cuya instalación ha destruido porciones significativas de la trama histórica. Estos méto dos no solamente destruyeron partes valiosas e importantes de las estructuras históricas; tam bién eran prohibitivamente caros. Dado la carestía y características invasivas de este método, se ha buscado con gran interés otros y mejores métodos para lograr rigidizar los sis temas. Por muchos años se ha estado traba jando con mucho empeño en todo el mundo con este objetivo. El terremoto de Northridge fue un hecho trágico pero que ocurrió en un momento cru cial en el desarrollo de una comprensión más amplia del comportamiento de las estructuras de ladrillos de barro y de la tecnología de refuerzo correspondiente. Un importante estu dio patrocinado por el Getty Conservation Institute (GCI) sobre protección de los edificios históricos de adobe en California tiene por objetivo desarrollar recomendaciones específicas para fortalecer estas estructuras usando métodos menos invasivos que los usados en el pasado. La investigación y pruebas de nuevos métodos de refuerzo aplicando simulaciones sísmicas esta ban ya bastante avanzados cuando se produjo el After being expensive. Given the expense and invasiveness of terremoto. Simultáneamente en otras partes del heavily dam this method, there was an increasing interest in mundo se estaban haciendo las mismas pruebas aged during the developing better methods for achieving system con los mismos objetvios básicos - proteger las Northridge Earthquake, rigidity. Significant work had been going on estructuras históricas de tierra con el mínimo Rancho around the world for many years to achieve that de intervención. Camulos was goal. A pocos días del sismo de Northridge un seismically strengthened by The Northridge earthquake was a tragic equipo de arquitectos, arquitectos conser less invasive event, but it came at a critical time in the recent vadores e ingenieros inició una inspección y approaches development of a greater understanding of the análisis sistemáticos de los daños. Hubo dos than usual. Photos courtesy performance of mud brick structures and appro aspectos importantes dentro de esta evaluación the author. priate strengthening technology. The goal of a y análisis de daños que no habían ocurrido major study sponsored by the Getty antes. Como el terremoto de Northridge ha Luego de sufrir graves daños Conservation Institute (GCI) on the protection sido el sismo más monitoreado de la historia, se durante el ter of California's historic adobe buildings was the pudo estudiar con mayor detalle todas las carac remoto de development of specific recommendations for terísticas reales del sismo y relacionarlas con los Northridge, se le hizo un strengthening these important structures using daños reales. Otro aspecto importante es que refuerzo antisís• less-invasive methods than had often been used los miembros del equipo de investigación ya mico con técni in the past. A great deal of investigation and test conocían las estructuras que en gran parte ya cas menos invasivas que ing of possible strengthening methods utilizing habían sido documentadas y analizadas por el las prece seismic simulation was well underway when the equipo del programa del Getty dos años antes dentes. Fotos earthquake occurred. Taking place at the same del terremoto. Este conocimiento sirvió cortesía del autor. time in other parts of the world was similar test- muchísimo para que los miembros del equipo
CRM No 6—1999 41 ing with the same basic goals—providing protec lograran comprender los efectos de las condi tion to historic earthen structures with the mini ciones pre-existentes, en relación con el nivel de mal amount of intervention. daños causados por el terremoto. El informe del Within days of the Northridge event, a estudio y su desarrollo y análisis posterior que team of architects, architectural conservators, and compara el hecho real con el daño específico engineers began a systematic inspection and causado en las estructuras respectivas es el más analysis of the damage. There were two impor exhaustivo de su tipo. Además, el informe tant aspects of this damage assessment and analy entrega una información muy valiosa sobre sis that had not occurred before. Because the tipología de fallas en estructuras de tierra y los Northridge earthquake was the most monitored efectos de las condiciones pre-existentes. of any earthquake in history, more detail of the Al desarrollar un sistema de protección actual characteristics of the event could be stud antisísmica para un edificio histórico es impor ied and related to the actual damage. Another tante comprender cuáles son los valores que important aspect was that members of the survey deben protegerse. Como ejemplo, los códigos team were already familiar with the structures, de construcción para refuerzo antisísmico están many of which had been previously documented orientados en primer lugar a proteger la vida and analyzed by the Getty program team two humana y no a proteger las estructuras. Incluso years prior to the earthquake. This familiarity en nuestro estado actual de conocimiento es contributed to the team members' understanding imposible reforzar una estructura de tierra para of the effects of pre-existing conditions in rela que no sufra ningún daño en un terremoto. La tion to the level of earthquake damage. The principal prioridad será siempre la protección report of that survey with subsequent develop de la vida humana. Si bien no puede eliminarse ment and analysis comparing the actual event to la posibilidad de daños, sí se puede diseñar un the specific damage to specific structures is the sistema que dirija el impacto de falla hacia cier most comprehensive of its type. In addition, the tas partes de la estructura o a sus aspectos report provides valuable information about fail menos relevantes. Una falla dirigida podría con ure typology of earthen structures and the effects sistir en aislar los componentes de dos construc of pre-existing conditions. ciones que en caso contrario podrían impactar When developing a seismic protection sys uno al otro durante un temblor. En la Misión tem for a historic building, it is important to San Gabriel de California, el baptisterio fue understand the values that are to be protected. As separado estructuralmente cortando a través de an example, building codes for seismic strength la mampostería, con lo cual ambos compo ening are directed first to the protection of nentes pueden moverse individualmente. human life and not to the protection of the struc Debido a sus relaciones geométricas específicas, ture. Even with our current state of knowledge, it si no se los hubiese separado habrían causado is impossible to strengthen an earth structure so graves daños al elemento vecino. Durante el that it will not suffer any damage during an terremoto de Northridge estos componentes earthquake. The first priority will always be the estructurales se movieron independientemente protection of human life. While all damage can y solamente se dañó la terminación de yeso que not be eliminated, a system can be designed so unía el corte en la mapostería. Esta es una that damage is directed to parts of the structure forma de falla dirigida. Puede haber otra forma or to its less significant features. Directed failure de falla dirigida adecuada para el caso de una can take the form of isolating two building com superficie original de yeso decorada que está ponents that otherwise might cause damage to intacta, como en la Misión San Miguel de one another during ground motion. At California. En este caso la superficie decorativa California's Mission San Gabriel, the baptistery no podría sobrevivir si los muros sufrieran was structurally separated by cutting through the grandes agrietamientos sin moverse. Se puede masonry, allowing the two components to move crear aquí un punto de quiebre que permita separately. Because of their specific geometric que los muros oscilen sobre sus fundaciones en relationships, if not separated, they could cause lugar de resquebrajarse. severe damage to one another. During the Como material de construcción la tierra Northridge earthquake, the two structural com no tiene elasticidad o ductilidad real y tiene ponents did move independently and the only escasa resistencia a la flexión. Un material dúctil
^2 CRM No 6—1999 damage was to the plaster finish that bridged the cotno el acero o la madera se puede deformar masonry cut. This is one form of directed failure. hasta cierto punto y luego vuelve a su forma Another form of directed failure might be appro original, conservando siempre su función priate if an original decorative plaster surface estructural. La piedra como material también es remains intact, such as at California's Mission San muy poco dúctil, pero es más fuerte que la Miguel. In this case the decorative surface would tierra compactada y puede resistir más carga not survive if the walls were extensively fractured antes de romperse. En los lugares en que los ter but remained in place. However, a weak point remotos son parte de la vida, la gente ha apren might be created that would allow the walls to dido a construir con material terreo con un sis rock on their foundations rather than fracture. tema de construcción que tiene un grado mayor As a building material, earth has no effec de ductilidad que la del propio material. En tive elasticity, or ductility, as it has little resistance muchas partes del mundo de conocida activi to bending. A ductile material, such as steel or dad sísmica la construcción tradicional utiliza wood, can deform to a certain degree and then muros de ladrillos de barro que soportan cargas return to its former shape and still perform its en la planta baja y encofrados de madera con structural function. Stone as a material also has ladrillos de barro no soportantes, o muros de little ductility, but it is stronger than compacted argamasa y fibras en los pisos superiores. Es un earth, and it can resist more loads before failing. sistema bastante dúctil y que ha demostrado su In places where earthquakes are an expected part sobrevivencia a las fuerzas de un terremoto. of life, people have learned to build with earth Otro método de refuerzo consiste en material using a building system that has a aumentar el comportamiento elástico de un sis greater degree of ductility than does the material tema. Si una estructura no puede rigidizarse, itself. In many parts of the world with known debe ser capaz de comportarse con un cierto seismic acitivity, a traditional building utilizes grado de elasticidad para poder sobrevivir a los load bearing mud brick walls on the first floor movimientos telúricos. Desde el punto de vista level and timber frame with non-load bearing de los sistemas constructivos, las cabanas de mud brick or waddle and daub walls on the troncos que soportaron el terremoto de New upper floors. The system is somewhat ductile and Madrid actuaron elásticamente, en el sentido often survives under the stresses of an earthquake. que se deformaron y luego recuperaron su Another strengthening method is to forma original sin sufrir daños permanentes. increase the system's elastic performance. If a Esta cualidad elástica se conoce como ductili structure cannot be made rigid, then it has to be dad. able to perform with a certain level of elasticity to El ejemplo más reciente de refuerzo de survive seismic ground motion. As building sys una construcción histórica de adobe que incor tems, the log cabins of the New Madrid earth pora los conceptos más avanzados es el Rancho quake were somewhat elastic in that they Camulos en el condado de Ventura, California, deformed and then returned to their previous aproximadamente 30 millas al norte de form without suffering permanent damage. This Northridge. Rancho Camulos fue una de las elastic quality is referred to as ductility. estructuras de adobe importantes que sufriera The most recent example of strengthening a grandes daños durante el terremoto de historic adobe building that incorporates the lat Northridge y fue incluida en la revisión poste est concepts is at Rancho Camulos in Ventura rior al sismo. Se dio rigidez a la estructura al County, California, approximately 30 miles reforzar los pisos del segundo nivel y determi north of Northridge. Rancho Camulos was one nados sistemas de muros, para que se compor of the important adobe structures that suffered taran como placas o diafragamas estructurales severe damage during the Northridge earthquake semirígidos. Se logró dar más ductilidad al sis and was one of the structures included in the tema con la instalación de una serie de cables y post-event survey. Rigidity was achieved by zunchos que, si bien no fueron diseñados para strengthening second story level floors and evitar resquebrajaduras o daños en un nuevo selected wall systems to perform as semi-rigid terremoto, podrían evitar la caída de los muros. structural plates or diaphragms. System ductility Este sistema permite que los muros se muevan was achieved by the installation of a series of pero no fallen. El proyecto Camulos fue mucho cables and straps that, while not designed to pre- más barato que otros sistemas de reacondi-
CRM No 6—1999 43 vent cracking or damage during another earth cionamiento más tradicionales que utilizan quake, would prevent the collapse of the walls. vigas de unión en las techumbres. This system allows the walls to move but not to El estado actual de los conocimientos fail. The Camulos project also was less costly sobre protección de edificios y monumentos than other more traditional retrofit systems that históricos de tierra ante movimientos de tierra utilize bond beams at the rooflines. inducidos por sismos pone el énfasis en ofrecer The current state of knowledge about pro un nivel aceptable de protección, produciendo tecting historic earth buildings and monuments el menor impacto posible en la trama histórica from seismic induced ground motion emphasizes o en los sistemas históricos de construcción. providing an acceptable level of protection with Este enfoque se basa en los sistemas construc the least impact on historic fabric or historic tivos existentes y no intenta alterar el sistema, building systems. The approach takes advantage como ocurrió en el pasado en los casos más of the existing building systems and does not try graves, donde se cambiaron sistemas de soporte to alter the system as happened in the most severe de carga construidos en tierra por hormigón cases in the past when earthen load bearing sys armado con un relleno de adobes. Cuando el tems were changed to reinforced concrete frames sistema original no es adecuado se deben tomar with adobe infill. When the original system is medidas para fortalecer la capacidad de inadequate, measures are taken to increase the respuesta del sistema. system's ability to perform. El trabajo continúa. Se ha aprendido The work continues. While much has been mucho pero la posibilidad de predecir cuándo learned, the ability to predict when an earth se producirá un terremoto y describir sus carac quake will occur and to describe its characteristics terísticas por anticipado es una ciencia por decir beforehand is at best an inexact science. What we lo menos inexacta. Lo que sí sabemos es que do know is that the "big one" will occur and that habrá un "Big One" y que habrá más monu more heritage monuments of earth will suffer mentos de tierra que sufrirán daños y serán damage and be destroyed. What was learned destruidos. Las lecciones del terremoto de from the Northridge earthquake is important, Northridge son importantes y nuestro desafío and our challenge—to improve the strengthening sigue en pie: mejorar los sistemas de refuerzo systems that will have even less impact on impor que tengan un impacto aún menor sobre los tant heritage values and can be implemented at valores patrimoniales y que se puedan poner en even lower costs—persists. práctica con costos aún menores.
References Referencias Earthen Building Technologies. Workshop on the Technologías de Construcción Terrea: Taller para la Seismic Retrofit of Historic Adobe Buildings. Preparación Sísmica en Edificios de Adobe. Report on the Workshop held March 10, 1995. Informe del Taller conducido el 10 Marzo de Pasadena, Calif. 1995 en Pasadena, California. Feilden, Sir Bernard M. Between Two Earthquakes. Feilden, Sir Bernard M. Entre Dos Terremotos. Roma: Rome: The International Center for the Study of Centro Internacional para el Estudio de la the Preservation and Restoration of Cultural Conservación y Restauración del Patrimonio Property, and Los Angeles: Getty Conservation Cultural, y Los Angeles: Getty Conservation Institute, 1987. Institute, 1987. Levy, Matthys and Mario Salvadori. Why the Earth Levy, Matthys y Mario Salvadori. Porque la Tierra Quakes: The Story of Earthquakes and Volcanoes. New Tiembla: La Historia de Terremotos y Volcanes. New York: W. W. Norton & Company, 1995. York: W. W Norton & Company, 1995. Tolles, E. Leroy; Frederick A. Webster; Anthony Tolles, E. Leroy; Frederick A. Webster; Anthony Crosby; and Edna E. Kimbro. Survey of Damage to Crosby; y Edna E. Kimbro. Medición del Daño a Historic Adobe Buildings after the January ¡994 Edificios Históricos de Adobe después del Terremoto Northridge Earthquake. GCI Scientific Program de Northridge, Enero de 1994. Reporte del Programa Científico del GCI. Los Angeles: Getty Report. Los Angeles: Getty Conservation Institute, Conservation Institute, 1996. 1996. Robinson, Andrew. Impacto Terrestre: Huracanes, Robinson, Andrew. Earthshock: Hurricanes, Volcanoes, Volcanes, Terremotos, Tornados y Otras Fuerzas Earthquakes, Tornadoes and Other Forces of Nature. Naturales. London: Thames and Hudson Ltd., 1993. London: Thames and Hudson Ltd., 1993. Anthony Crosby recién jubiló con 25 años de servicio en Anthony Crosby recently retired after 25 years with the el National Park Service y ahora trabaja en la conser National Park Service and is currently in private architecvación de arquitectura. tural conservation practice.
44 CRM No 6—1999 Ann Rasor Nuestra Señora del Pilar y Santiago de Cocóspera
...a single human hand with a bit of ...con sólo un poco de suave barro new soft mud is quicker than time nuevo, una mano humana es más and defies the centuries... rápida que el tiempo, desafiando D. H. Lawrence, Mornings in Mexico los siglos... D. H. Lawrence, Mornings in Mexico o one who looks upon Cocóspera can forget her. At adie que haya posado sus ojos first glance you think she is en Cocóspera podrá jamás gone, but when you get to olvidarla. A primera vista, da know Nher you realize that even though she is la impresión que ya no está crumbling, her heart and soul still beat within. allí, perNo una vez la conozcan se darán cuenta She wants to tell you her story. que aunque se esté desmoronando, su corazón y Founded in the late-17th century, Nuestra su alma aún laten en su interior. Ella quiere Señora del Pilar y Santiago de Cocóspera served narrarles su historia. nobly as one of the Kino mission chain until the Fundada a finales del siglo 17, Nuestra mid-19th century; today it still guards its name Señora del Pilar y Santiago de Cocóspera sirvió sake valley about 40 miles west of Imuris, Sonora, noblemente como parte de la cadena de Mexico. Just 35 miles (as the crow flies) from the misiones Kino hasta mediados del siglo 19. United States-Mexico border, one finds a church Hoy día aún domina vigilante sobre el valle que whose roof is gone, whose facade is broken and lleva su mismo nombre, a unas 40 millas al leaning, and whose interior teases us with traces occidente de Imuris, Sonora, México. A tan of gilded and painted designs and elaborate plas sólo 35 millas (lo que vuela el cuervo) de la ter work—elements that set her apart from her frontera entre los Estados Unidos y México se neighboring missions. encuentra una iglesia que no tiene techo, cuya Can something be done to help her? This fachada está rota e inclinada y cuyo interior nos was the question put forth during an intriga con sus huellas de diseños dorados y International Earthen Architecture Conference pintados y con complejas obras de emplasto, sponsored by the National Park Service and the siendo estos elementos los que la distinguen de Institutio Nacional de Antropología e Historia misiones vecinas. (INAH) in September 1998. Attendees at the ¿Hay algo que se pueda hacer para ayu conference included preservation experts, restor darla? Esta fue la pregunta que surgió durante ers, and archeologists from 13 different agencies una Conferencia Internacional Sobre on both sides of the border. It was agreed then Arquitectura de Tierra auspiciada por el that if a time could be established and some National Park Service y el Instituto Nacional de modest support given, many of the attendees Antropología e Historia (INAH) en septiembre would return for a week to help Cocóspera sur de 1998. Entre los asistentes a la conferencia se vive. Using contacts established during years of encontraban expertos en conservación, restau working on preservation projects in Mexico, radores y arqueólogos provenientes de trece David Yubeta, exhibit specialist at Tumacacori (13) entidades diferentes en ambos lados de la National Historical Park in Tucson, Arizona, frontera. Se acordó que si se lograba establecer immediately began organizing the project. With un marco temporal y se obtuviera un modesto INAH's blessing and support from the Southwest apoyo financiero, muchos de los asistentes Mission Research Center, Tucson, Arizona, and regresarían durante una semana para ayudar a the National Park Service Mexican Affairs Office, que Cocóspera sobreviviera. A través de contac Las Cruces, New Mexico, an exceptional group tos hechos durante años de trabajo en proyectos assembled at Cocóspera during the week of de preservación en México, David Yubeta, un March 16, 1998. Especialista en Exhibiciones del Parque
CRMN06—1999 4S The group had three days to work on a site Histórico Nacional de Tumacacori en Tucson, that needs three years! The main objectives were Arizona, se dio de inmediato a la tarea de orga emergency stabilization and the development of a nizar el proyecto. Durante la semana del 16 de strategic plan for preservation. The multidiscipli- marzo de 1998 y con la aquiescencia de INAH nary team provided a complete package of y el apoyo del Southwest Mission Research research and hands-on preservation specialties. Center de Tucson, Arizona y del National Park Within 36 hours the group accomplished an Service Mexican Affairs Office de Las Cruces, archeological survey, tree-ring dating, a construc New Mexico, se logró finalmente reunir un tion history, plaster restoration, and emergency grupo excepcional de personas en Cocóspera. stabilization. ¡El grupo contaba con tres días para traba Cornerstones Community Partnerships staff jar en un sitio que realmente requería de tres from Mesilla, New Mexico joined National Park años! Los objetivos principales eran ante todo Service preservationists from all over the south una estabilización de emergencia y el desarrollo west to repair severe erosion on the lower areas de un plan estratégico de preservación. Este of the church's massive adobe walls. Fortunately equipo multidisciplinario proporcionó un more than 100 pieces of original wood remain in paquete completo de especialidades prácticas e the structure, and a crew carefully obtained over investigativas de conservación. Luego de 36 30 samples for the University of Arizona Tree horas de trabajo, el grupo completó el levan Ring Laboratory to date and analyze. tamiento arqueológico, determinación de Archeologists from the United States Forest fechas por anillos de los árboles, una reseña INAH and Service and the Bureau of Land Management American con histórica de la construcción, restauración de servators dis with the assistance of the Southwest Archeology emplastos y estabilización de emergencia. cuss treatment Team (SWAT) surveyed and mapped sites on El personal de Cornerstones Community strategies at three river terraces. Among their discoveries were Cocóspera. Partnerships de Mesilla, New Mexico, junto the mission's lime and brick kilns. Southwest Photo courtesy con presentadores del National Park Service Nyle Leatham. Mission Research Center members assisted provenientes de todo el sudoeste unieron sus National Park Service historical archeologists in INAH y esfuerzos para reparar la severa erosión en la Americano sorting and identifying the thousands of pieces of parte inferior de los enormes muros de adobe conservadores fallen church plaster. Photographers worked to de la iglesia. Afortunadamente aún existen más discuten fully document the project including the map tratamientos de 100 piezas de madera originales en la estruc estrategias en ping of the church walls and keeping a registry of tura y el equipo logró extraer cuidadosamente Cocóspera. work accomplished. E. Ramón Hinostroza, más de cien muestras para ser fechados y anal Foto cortesía Director of Centro INAH, Sonora, Mexico, and Nyle Leatham. izados por el Laboratorio de Anillos de Arboles his staff provided daily project support consulting de la Universidad de Arizona. Arqueólogos del U.S. Forest Service y del Bureau of Land Management, con la ayuda del Southwest Archeology Team (SWAT) estudiaron y car- tografiaron sitios ubicados en tres diferentes ter razas ribereñas. Entre sus descubrimientos se encuentran los hornos de cocción y secado para cal y ladrillos de la misión. Miembros del Southwest Mission Research Center, ayudaron a los arqueólogos históricos del National Park Service en la clasificación e identificación de los miles de trozos de yeso caído en la iglesia. Un grupo de fotógrafos se dedicó a documentar totalmente el proyecto incluyendo una car tografía de las paredes de la iglesia y además lle var un registro del trabajo logrado. E. Ramón Hinoztrosa, Director del Centro INAH de Sonora, México, junto con su personal, propor cionaron apoyo diario al proyecto, brindando asesoría continua a medida que las actividades
46 CRM No 6—1999 continously as activity progressed and officially progresaban y llevando un registro oficial del recording the project. INAH architects and proyecto. Arquitectos y restauradores del INAH restorers spent the week perched precariously on estuvieron toda la semana trepados peligrosa scaffolding laboriously re-attaching sections of mente en andamios, cuidadosamente pegando the remaining church plasters and conserving secciones de los restos del emplasto de la iglesia plaster that had come loose. Their openness to y preservando las partes sueltas. La apertura de exchanging ideas and their generosity in allowing estas personas hacia el intercambio de ideas y su foreign hands to touch this significant national generosidad puesta de manifiesto al permitir treasure cannot be over emphasized. que manos foráneas tocaran este gran tesoro The Cocóspera project paved the way for nacional ha sido inapreciable. other cooperative projects. Several months later, El proyecto Cocóspera preparó el camino colleagues from INAH worked on adobe and para otros proyectos de cooperación. Meses más lime plaster conservation at Swansea, the Bureau tarde, colegas del INAH estuvieron trabajando of Land Management site near Lake Havasu, en la conservación de adobe y encalados en Arizona. In April 1999, they trained Forest Swansea, un emplazamiento del Bureau of Service employees in interior plaster replication Land Management cercano a Lake Havasu, techniques at Kentucky Camp on the Coronado Arizona. Más tarde capacitaron a los empleados National Forest as a part of a Passport in Time del Forest Service en las técnicas de reproduc project. ción de emplasto interior como parte del What lies in Cocósperas future? Of great proyecto Pasaporte en el Tiempo. importance is community involvement. ¿Qué le deparará el futuro a Cocóspera? Cocóspera cannot survive unless she is cared for La participación comunitaria es de gran impor by those who share her history. tancia ya que Cocóspera no podrá subsistir sin The team concurred that the most efficient los cuidados de aquellos que comparten su his way to halt rapid deterioration is to give toria. Cocóspera a shelter and design is underway. Todo el equipo estuvo de acuerdo en que When the design and engineering have been la forma más eficiente de detener el rápido approved, fund-raising efforts to finance its con deterioro es dotar a Cocóspera de un resguardo struction will begin. o refugio, cuyo diseño se encuentra actual The Cocóspera project was a first; here pro mente en progreso. Una vez que el diseño y el fessionals from the United States and Mexico proyecto de ingeniería sean aprobados, se ini worked side by side on the preservation of ciarán los esfuerzos para reunir los fondos nece Nuestra Señora del Pilar y Santiago Cocóspera, sarios para financiar su construcción. an important landmark in Sonoran history. Even El proyecto Cocóspera fue un pionero en though Cocóspera rests in Sonora, Mexico, her su clase. En él, profesionales provenientes de los story is our story, too—it is only an inconsequen Estados Unidos y México trabajaron codo a tial political border that separates us from the codo en la preservación de ese importante hito Sonoran region, people, and history that we both de la historia de Sonora que es Nuestra Señora share. del Pilar y Santiago de Cocóspera. Aunque Cocóspera yace en Sonora, México, su historia Ann Rasor is Superintendent ofTumacacori National es también la nuestra y solo inconsecuentes Historical Park, Tucson, Arizona. límites geopolíticos son los que nos separan de la región Sonorense, de su gente y de nuestra historia común.
Ann Rasor es la Superintendente del Tumacacori National Historical Park en Tucson, Arizona.
CRM No 6—1999 4? Conservation of Earthen Conservación de la Architecture along the Arquitectura de Tierra a lo Borderlands largo de las Fronteras a National Park Service United States- he National Park Service United States- LMexico Affairs Office (MEAF), ubicada en TMexico Affairs Office (MEAF), located la Universidad del Estado de Nuevo México en Las at New Mexico State University in Las Cruces, Cruces, Nuevo México, continúa organizando y facil New Mexico, continues to organize and facilitate itando iniciativas en pro de la conservación cultural a international cultural conservation initiatives along lo largo de la región limítrofe entre los Estados the United States-Mexico border region. In collab Unidos y México. MEAF, en conjunto con otras enti oration with other United States-Mexico organiza dades tanto estadounidenses como mexicanas, orga tions, the MEAF staff organizes international niza foros y actividades culturales de carácter interna forums and educational activities on methods to cional sobre métodos que permitan preservar el patri better preserve both countries' earthen architectural monio histórico de la arquitectura de tierra en ambos heritage. This heritage includes earthen archeologi- países. Este patrimonio histórico incluye lugares cal sites, adobe buildings, and still-inhabited dis arqueológicos de tierra, construcciones en adobe y tricts along the border states. distritos aún habitados en los estados limítrofes. Forums have been coordinated in cooperation Varios foros se han coordinado en cooperación with the Instituto Nacional de Antropología e con el Instituto Nacional de Antropología e Historia Historia (INAH) in Mexico. The collaboration has (INAH) de México. Este trabajo en conjunto ha pro resulted in a number of symposia and workshops ducido numerosos simposios y talleres en ambos on both sides of the border that are similar to the lados de la frontera, muy similares al taller sobre Cocóspera workshop featured in the accompanying Cocóspera que aparece en el artículo adjunto (el article (see Rasor article, p. 45). The goal of such artículo de Rasor, p. 45). El objetivo de tales encuen gatherings is to provide opportunities for the can tros es facilitar un intercambio espontáneo y con did and constructive exchange of information structivo de información sobre técnicas para la preser regarding adobe preservation techniques. vación del adobe. Como resultado de estos foros Numerous binational projects that have resulted internacionales, se han llevado a cabo numerosos from these international forums include the publi proyectos binacionales, entre los cuales merecen ser cation of the symposia proceedings, the compila destacados: la publicación de las actas de los simpo tion of traditional technical methods of working sios, la compilación de métodos técnicos tradicionales with adobe materials, the preparation of condition para trabajar con materiales de adobe, la elaboración assessments, interventions at adobe sites in need of de evaluaciones de condiciones, intervenciones en emergency repairs, instruction in the use of lime emplazamientos de adobe que requerían reparaciones plastering techniques, and the preparation of site de emergencia, instrucciones para el uso de técnicas management plans. de encalado y la elaboración de programas de admin The interaction of practitioners along the istración de sitios. border states has enabled a broader understanding La interacción entre profesionales de los estados of common building practices and traditions and limítrofes ha permitido un mejor y más amplio provided opportunities for experts to share infor entendimiento sobre prácticas comunes de construc mation about preservation techniques. This ción, además de proporcionar a los expertos la opor exchange helps to perpetuate the sustainable tradi tunidad de compartir información sobre técnicas de tions of building with adobe. preservación. Este intercambio ayuda a perpetuar las For more information, contact the National tradiciones sostenibles de construcción con adobe. Park Service United States-Mexico Affairs Office at Si desea mayor información, póngase en con 505-646-7880. For more information on our office tacto con la National Park Service United States- and upcoming international activities, please access Mexico Affairs Office al teléfono No. 505-646-7880. our web page
48 CRM No 6—1999 David G. Anderson and Michael Russo Native Earthen Architecture in Eastern North America
or at least 7,000 years people in were a major source of food, as in coastal and eastern North America have made riverine areas of the Southeast, the resultant use of earth as a building material. architectural features stood as high as 15 meters Accumulations of various types of and often were hundreds of meters long. earth,F including sand, loam, humus, clay, silt, Although often distinguished from mounds com muck, and loess, often in conjunction with other posed primarily of excavated soil by being called natural materials such as shell and stone, have "incidental" rather than "purposeful" construc been used to bury the dead, raise the living above tions, their sizes and geometrically distinct shapes the floodplain, elevate the social elite above the belie this notion. These shell mounds served the masses, symbolize political boundaries and same architectural functions as places of burials, mythic beliefs, and demarcate both sacred and enclosure, habitation, and symbolization as did secular space, transforming the natural world into their strictly earthen counterparts. a humanly defined landscape. Today, across the The effort required of leaders to gain the great expanse of the eastern United States, thou cooperation of builders to excavate earth and sands of mounds and other mounded earthworks determine areas to place the building material, remain as tangible evidence of hundreds of now- combined with the ceremonial and ritual behav vanished societies. ior that went along with the construction, served The variety of mounded earth formations to bring people together and substantiate their included enclosures of public places, burial culture. Earthworks were viewed as symbols of mounds of single individuals and multiple inter the groups that made them, and they indicated ments, mounds without burials that served as their tenure in that area. public monuments, places where communal Historical Trends in Earthen feasting and ritual occurred, and elevations upon Construction which the temples and residences of hereditary The earliest known earthen construction in elites were placed. Monks Mound, an edifice near Eastern North America dates to about 7,500 St. Louis, Missouri, was a truncated pyramid years ago. Located at LAnse Amour, Labrador, it measuring 300 meters on each side and nearly 30 is a burial mound of a child, and it measures 10 meters high. Built between c. A.D. 1000 and meters in diameter and 1.5 m high. The mound 1200, it reflects the intentional activity of thou was built by a small group of egalitarian hunter- sands of people working together Typical over long periods of time. Mississippian However, the most prosaic of temple mound complex c. prehistoric mounds, often called 1200-1450, mounded middens, were simple southeastern garbage dumps resulting from United States. the disposal of cooking scraps and other debris. When used for short periods of time by few peo ple, they may not have stood more than a few centimeters above the surrounding landscape. When commingled with accu mulated soil, however, over time substantial mounding could result. In areas where shellfish
CRM No 6—1999 49 gatherers, typical of the kinds of societies that America. Remains of wooden structures, large sparsely populated North America at the time. sand and shell mounds, and a "ring" midden, By 5,000 years ago egalitarian hunter-gath which surrounded the site, indicate a relatively erers still roamed the East, but populations had complex society compared to those that preceded grown, and much larger earthworks began to it. This site combined with the contemporary appear. At the Watson Brake site in Louisiana, for mound complexes in Louisiana (which were example, a complex of 11 mounds was built occupied seasonally), were places where large between c. 5400 and 5000 B.P. The site extends numbers of people came together for at least over 300 meters, with seven of the mounds tied some extended periods, and is the earliest evi together by a circular earthen embankment. It is dence of the first steps toward the creation of but the largest and most dramatic of a number of more complex social organizations such as tribes, mound complexes built around this time in the and eventually chiefdoms, which later built the Lower Mississippi Valley. majority of earthen works in the East. At the same time, large mounded shell and The "ring" motif in monumental earthen earthen sites were made along many of the rivers architecture at Watson Brake and Horr's Island in the interior as well as along the Southeastern reached it apogee 1,000 to 2,000 years later on coasts. The interior riverine "Shell Mound the coasts of South Carolina, Georgia, and Archaic" cultures of Kentucky and Tennessee par Florida, where scores of circular shell rings up to ticipated in long-distance exchanges with soci four meters in height and ranging between 50 eties in other parts of the continent, exchanging and 280 meters in diameter were built from shell valuable raw materials like conch shell from the and earth between 4,200 and 3,000 years ago. Atlantic and Gulf coasts and copper from the Their function is debated, but it is known that Great Lakes as well as elaborate finished goods, people lived on or adjacent to the rings, and the such as grooved and polished axes and decorated center "plazas" were kept clean, perhaps for pub bone pins. Competition between individuals and lic ceremony. societies for status increased and evidence of war At about the same time, a most impressive fare appears in burials with embedded projectile monumental earthen architectural center was points and other weapons trauma. These built at Poverty Point, Louisiana. The site con mounded middens sometimes contained formal tains a massive earthen mound, built in the ideal cemeteries demarcating kin groups and territory. ized shape of a bird measuring more than 100 Elsewhere, a notable shell-earthwork dating meters long and over 20 meters high, with six to 5,000 years ago is found at Horr's Island along concentric earthen ridges extending almost one the southwest Florida Gulf coast. There, analysis kilometer in diameter. The site is the largest feast of food remains indicates a permanently settled ing and trading center of a number of mound community, the oldest known from North centers built by this culture, which participated in a vast exchange network Pritchard spanning much of the lower Landing, a Southeast. Middle wood Beginning about 3,000 land mound complex c. A.D. years ago, groups throughout 800, Ouachita the Southeast and Midwest Valley, Louisiana. began a tradition of burying their dead in or below earthen mounds. Some of the earliest such mounds were small, and individuals were buried with out elaborate burials goods. Collective burials were often placed in larger conical or rounded mounds. In these early mounds, most members of society were allowed burial entry; however, over time
SO CRMN06—1999 Horr's Island, a mound burials were increas Late Archaic ingly reserved for higher-sta earthen and shell mound/ring tus individuals, leaders in complex c. ceremony and exchange. As 5,000 B.C., populations increased, cer southwest Gulf coast Florida. tain elites gained more power and prestige. These individuals were the coordi nators of the ceremonial and exchange network, directed monumental construction at the centers, and were privi leged to receive elaborate burial treatment. High-sta tus individuals have been found in log-lined tombs with rich grave offerings, and others beneath conical mounds massive in extent or intricately constructed of differing textured and Over time, the nature and function of colored soils. A ceremonial and exchange net mound complexes in the eastern North America work spanned much of the region at this time, changed. By A.D. 800, the individualistic geo and massive mound and earthwork complexes metric mound complexes that characterized ear were built in several areas, including the Pinson lier constructions had largely disappeared. Large site in western Tennessee, Marksville in mound and plaza complexes were now function Louisiana, and Kolomoki in Georgia. Numerous ing as administrative and ceremonial centers of other equally large and smaller centers dotted the larger, hierarchically organized agricultural soci Eastern Woodlands. eties, or chiefdoms. Flat-topped mounds were In southern Ohio, the elaborate vast now used as platforms upon which temples and earthen enclosures of the Hopewell culture were elite residences were built, facilities reserved for built between 2,200 and 1,700 years ago. Some the highest members of society. Some centers covered tens of acres and were shaped like circles, were the largest ever constructed in the East. The rectangles, squares, or octagons, often with long largest center, Cahokia in southern Illinois, causeways leading to them. At this time effigy encompassed hundreds of hectares and well over mounds were also constructed in the shapes of 100 mounds. animals such as snakes, birds, panthers, lizards, Although the rise of mound-building in the and humans throughout the Midwest; while in eastern United States has often been linked to the Everglades, strangely shaped and designed influence from complex cultures of South sites such as Fort Center, consisted of linear America and Mexico, no direct influence from earthen embankments, mounds, ditches, and these distant cultures has ever been found. The circles. unique and ubiquitous traditions of mound Besides extensive geometric earthworks, building found throughout eastern North flat-topped mounds resembling truncated pyra America have always been indigenous phenomena. mids also appeared in several areas around the David G. Anderson and Michael Russo are archeologists time of Christ, notably in the Southeast. These with the Southeast Archeological Center of the National mounds appear to have been elevated stages Park Service in Tallahassee, Florida. where collective ceremony and feasting occurred. Some sites were large, with numerous mounds All paintings by Martin Pate. Photos cour and extensive earthworks, while other sites were tesy National Park Service Southeastern small, little more than single mounds that may Archeological Center and (this page) Collier have served as simple shrines. Country Museum, Florida.
CRM No 6—1999 51 Jake Barrow Against the Odds—Hottai Ki
... only a huge dun colored, almost shapeless tion and destination for visitors thereafter. One mass, looming up strangely from the desolate may assume that natives of the area were well plain. There is nothing architectural about the aware of the structure over the centuries since structure. It is, at best, but a mud house; though, abandonment and had some use for and of it. Sketches, written descriptions, and the first pho as he examines it more closely, it seems more tos taken in 1877 provide a wealth of informa and more wonderful, and the mind is filled with tion from which to discern conditions of the conjecture as to the uses to which this great structure since Kino's first observations. The building may have been put, and why it stands so 1877 photographic record is a watershed in the lonely and isolated. process of documentation, which is essential to J. Z. Stewart* establish rate of change. Researchers draw on these documents now, as they did in the past, to n 1879, geologist Professor George discern gross changes. Cook participated in the first scientific examination of the earthen materials Constructed of puddled earth in about of the Casa Grande, then over 600 1250 by the Hohokam (whose name means I "those who have gone") and used through 1400, years old. His observations started a preservation process that continues today. In 1892, national the site appears to have been abandoned around interest in this earthen ruin led to the first feder 1450. The Hohokam, occupiers of the northern ally funded stabilization project on an archeologi- Sonoran desert, now south central Arizona, left cal site in America. By 1903, a shelter over the no written record; they did, however, achieve site had been constructed, after due considera technical mastery in earthen architecture and left tion, even though surveys, historical commen treasures of artifacts and a major regional canal tary, and professional judgment indicated that irrigation system. Oral tradition is held by their some of the parapet top courses and wall surfaces descendants, American native occupiers of the were nearly as they were at construction. These region today—the Pima Indians. walls built of puddled caliche-rich earth have After abandonment, roof and floor timber withstood seasons of weathering, earthquakes, were recycled into other uses and the natural and the destructive forces of man for more than processes of decay and the associated deteriora half a millennia. This remarkable history illus tion caused by human hand took a toll until the trates a perhaps never-ending story of engage federal government intervened and officially took ment with the material and myth of one of control of the site in 1892. Preservation started in Americas most prominent earthen monuments. 1891 when Cosmos Mindeleff, anthropologist To consider its tenure one must approach the for the Bureau of American Ethnology, managed place with a measure of reverence and awe. the first stabilization effort. Several 19th-century anthropologists had preceded him to visit the site Jesuit priest Eusebio Kino first popularized including Adolf Bandelier in 1883. Commentary, Casa Grande when he was led by Native ideas, and proposals were developing and avail Americans to see the Hottai Ki (Great House, in able. Under Mindeleff's general supervision, the native tongue) in 1694, and it became an attrac- site was cleared, braces were installed, and under pinning was added. The idea of a shelter was con "Ancient Ruins in Arizona." Juvenile Instructor 12 sidered, disputed, and not resolved immediately. (January 15, 1877): 21-22. Hanks, Henry Garber. Photographic evidence indicates that the earth "Casa Grande." Californianl (August 1880): 104. quake of 1887 (the last major seismic event From "A Centennial History of the First Prehistoric recorded in the northern Sonoran desert) may Reserve: 1892-1992," A. Berle Clemensen, p. 23, have caused several major wall section collapses; Administrative History, United States Department and Mindeleff's work was clearly an attempt to of the Interior, National Park Service, 1992. re-establish the perceived lost stability. Records
52 CRMN06—1999 West elevation, do not indicate that he con The Great sulted with an engineer; rather, House, Casa Grande ruins. it appears that the gestation of ideas developed during the pre vious decade was distilled into a plan of action. Contemporary technical evaluations of this 1891 work aside, the effort reversed the trend of neglect, turning the tide of "grave rob bing" destruction that had been increasing on site since the rail road came in 1879 and 1880. The timber shelter with a sheet metal roof was finally built in 1903, also without the benefit of formal architectural or engineer ing services. no degradation, appearing as they would have in The original shelter was replaced with a the 1400s. designed and engineered steel frame shelter in As of 1996, the Western Archeological 1932 (itself placed on the National Register). Center (of the National Park Service in Tuscon, Current assessments indicate the efficacy and Arizona) bibliographic references on this subject value of sheltering the site. exceeded 100 documents, books, and reports, Current Program indicating a wealth of studies and information. In 1999 the effort is continuing. A review Little of this material sheds light on an under of the 20th-century activity reveals a history rich standing of the physical changes of the struc with proposal and treatment alternatives— ture—the rate of change, the causes for change, cement stabilization, plans to infiltrate the soil and the fundamental structural capability as orig with epoxy, geodesic dome covers, modern syn inally conceived and as it is today. The current thetic elasticized soil amendments, bricks and program was initiated following the 1995 col mortar underpinning, un-engineered stabilizing lapse of a 6-cubic-feet piece. Since the late 1980s, systems, wall monitors, material studies, docu hands-on routine type preservation had been sus mentation programs, test wall programs, sur pended. The routine preservation maintenance rounding terrain modification, technical scien actions would probably not have prevented the tific excursions, and many anthropologic studies. failure of 1995; and over the years several such Each effort was well intentioned and of more or sectional collapses are recorded. The current less value depending on viewpoint. After all that effort seeks to consider all previous work, sift has occurred the structure retains a remarkable through evaluations, assess treatments, and percentage of integrity. An astonishing recogni review as many points of view as possible. tion is that much of the remaining painted and Perhaps most important is a re-examination of unpainted interior surface plasters show little to the structure that takes into account the builders' original intent. What was there, what is there, and why are changes taking place? East elevation, In 1996 work began with a partnership The Great House, Casa planning team made up of the Arizona State Grande ruins. Historic Preservation Officer, the Architectural Conservation Laboratory in the Graduate Program of Historic Preservation at the University of Pennsylvania, and National Park Service staff. The University of Pennsylvania has for eight years partnered with parks in the Southwest to answer difficult research questions, develop pilot preservation programs, and assist with training activities through the cooperative
CRM No 6—1999 53 from weakening substrates and strengthening sur faces. Most of this action probably occurred before the structure was sheltered. Engineering work clarified the viability of the original architecture. A model of the struc ture, which included the diaphragm floor and ceiling systems, performed even while any single component could not withstand even dead loads. A rather sophisticated understanding of architec tural requirements emerges presumably resulting from empirical knowledge by the builders. Without the original structural fabric in place, the remaining walls are compromised and perfor mance is marginal. The seismic data combined to inform the team of real concerns regarding the viability of Casa Grande in a contemporary University of agreement process. Many of these activities have earthquake. Continuing engineering work is Pennsylvania focused on earthen architectural issues, which for envisioned and plans for revised monitoring are 1998 Field some time now have not had the attention of School survey in the works. Difficult decisions for management ing interior walls. other more responsive architectural fabrics. lie ahead, and no ready-made methodology is At Casa Grande two concurrent winter field anticipated. schools documented, surveyed, and assessed con Continued monitoring, stabilization, and ditions evident from surface observations. preservation programs are taking place at Casa Students mapped details of conditions across the Grande. New findings offer information for surfaces, a complete 100%-coverage photo-docu interpretive agendas. On the one hand, reassur mentation was accomplished, and an engineering ance of the test of time leads to limited objec assessment was made. Throughout these cam tives; on the other hand, localized and continuing paigns the Arizona State Historic Preservation deterioration begs for attention and action. Officer and staff participated in planning. Regardless of approach, the sustaining preserva Analysis sessions were periodically held at the tion principle at this stage should be to maintain park and at the University; during these forums, a graceful, long, and dignified old age for the participants stood in front of scaled digitized deserving Hottai Ki. color annotated elevations considering patterns, clues, and other information pertinent to the Bibliography ruin's condition. Two graduate students under Clemensen, A. Berle. A Centennial History of the First took thesis topics that involved researching fun Prehistoric Reserve: 1892-1992, March 1992, damental questions about material, architecture, Administrative History. Casa Grande Ruins and deterioration mechanisms. Engineers simul National Monument, United States Department of taneously engaged in assessing the structure. In the Interior, National Park Service, 1992. Matero, Frank. Documentation and Assessment of Wall addition, seismic evaluations of the structure in Conditions, The Casa Grande, Casa Grande Ruins relation to potential earth tremors were made. National Monument. Unpublished Report for Results are coming in. Materials research National Park Service, 1999. findings have suggested a theoretical concept that Del Bono, Elisa M. Characterization and Analysis of the appears astonishingly simple, yet of lasting and Caliche Walls of the Great House, Casa Grande Ruins profound implication relevant to our considera National Monument. Master's thesis in Historic tions. Laboratory testing of samples taken from Preservation, University of Pennsylvania, 1999. the 1995 collapsed piece showed a migration of Gift, Andrea, and G. Eric Johansen. Casa Grande, A Preliminary Structural Review. Unpublished Report calcium carbonates from the substrates to the sur Photos cour for the National Park Service. Department of face in the form a kind of case hardening of the Engineering, University of Pennsylvania, 1998. tesy the surface. One master's thesis defines and charac author. terizes this phenomenon in detail. This factor Jake Barrow is Senior Exhibit Specialist in the could explain the resistance of the surface to Architectural Conservation Projects Program, direct water abrasion and the accompanying phe Intermountain Region, Santa Fe Support Office, nomenon of detachment of sections resulting National Park Service.
S4 CRM No 6—1999 Robert Hartzler Holding Down the Forts The Army, Adobe, and Preservation
n August of 1846, U.S. Army General isolation, and the climate. And of the forts that Stephen Watts Kearny climbed atop a survive, each is unique in its preservation. low, flat-roofed adobe building over This article presents four forts in the arid looking the plaza of Las Vegas, New Southwest that are actively interpreted to the MexicoI. From his earthen podium he proclaimed public, physical evidence of approximately 40 to the citizens of the village that they no longer years of settlement, struggle, and a harsh life on owed allegiance to Mexico. It was Kearny's first this new American frontier in the last half of the official stop on his way to Santa Fe with the 19th century. The four forts are Fort Bowie, over "Army of the West" to announce that henceforth, looking Apache Pass in the Chiricahua the northern territories of Mexico were now Mountains in southeast Arizona; Fort Davis, at under the control of the United States govern the mouth of a canyon in the Davis Mountains ment. in west Texas; Fort Selden, on the Rio Grande in With the signing of the Treaty of southern New Mexico on the Camino Real; and Guadalupe-Hidalgo at the conclusion of the Fort Union, on the Santa Fe Trail and the high Mexican-American War, a vast territory—includ plains of northeastern New Mexico. All are units ing most of present-day Texas, New Mexico, of the national park system except Fort Selden, Arizona, California, and Utah—suddenly which is a New Mexico State Monument. demanded attention, and the U.S. Army found What these forts have in common is that itself obligated to a vast, arid, sparsely populated they were constructed nearly entirely, or in part, region, inhabited primarily by immigrants from of adobe, and they share the modern problem of Spain and Mexico, and by American Indians, preserving such a fugitive material. Adobe con who considered the settlers of European heritage struction is a good choice for arid climates to be interlopers. because its principal agent of destruction, water, Sun-dried earthen bricks, adobe, were a is in short supply. But it does rain and snow and Spanish import to the New World. Their use blow in arid climates, and adobe left unsheltered among Native Americans was rare, although is vulnerable. And while adobe requires little cap other earthen architecture forms were not. The ital, it requires constant maintenance to fix leaky advantages of adobe in the Southwest were obvi roofs, repair failing plasters, and replace erosion ous. It required only soil with enough clay to act and loss. as a binder, water from a creek or river, and labor. Made in wooden molds and Fort Union, New Mexico, post dried in the sun, the earthen hospital in win bricks could be easily formed ter. into houses, stores, government buildings, and—as the army would soon demonstrate—forts. Each fort was unique in design and construction, depending on its purpose, loca tion, and availability of building materials and craftsmen. Later, each fort was unique in its aban donment, depending on the army's plan of retreat, the fort's
CRM No 6—1999 ss dows, and hardware— virtually anything use ful—dissolved into the surrounding communi ties. What remained, the adobe and the founda tions, was left to the elements. Each fort passed into private ownership, and over the years van dals, picnickers, and ranchers gave nature an assist and inflicted even more damage. The preservation, or the state of ruination, at each site tells a story. And each has a complex, and continually evolving preservation history. Fort Bowie National Historic Site Fort Bowie is located near the summit of Apache Pass, in the Chiricahua Mountains in southeastern Arizona. For centuries Apache Pass was an important crossing point due to the nat Wall fragments Military records of the day reveal that pre ural springs that occur there. Troops stationed at at Ft. Selden, serving the structures during their heyday was no Fort Bowie were involved in some of the most New Mexico picnic: hard-fought battles between soldiers and Indians State in the American Southwest during the last half of Monument. Indeed, from the moment they were com pleted until their abandonment in 1891, the the 19th century, including battles with Apache fort's adobe structures were in an almost con leaders Cochise and Gerónimo. stant state of unremitting deterioration. The The first Fort Bowie was established in territorial style of architecture [at Fort Union] 1862. In 1869 it was replaced by a larger post proved to be lamentably inadequate on the built nearby. Both were primarily adobe. The exposed plains of eastern New Mexico. The flat, tin-covered roofs were unable to provide post survived until 1894. Now Fort Bowie con sufficient protection from the wind-driven sists of the stone foundations of both forts, and rain and hail storms which plagued that level some adobe wall fragments of the second. In the open country. As a result, cracks developed, initial stabilization campaign of 1967 and 1968, water seeped through the roofs and walls into the adobe wall fragments were capped with soil- the adobe, walls separated from the roofs and cement adobes (earth amended with Portland threatened to collapse, and floors and foun cement), and some soil-cement veneer bricks dations rotted. The physical decline of the structures was hastened by two additional fac were placed to protect weathered walls. Because tors: the inability of the troops to perform the of aesthetic considerations and concern that the necessary repairs at a time when strict econ soil-cement adobes were causing erosion, nearly omy measures prohibited the employment of all the soil-cement adobes were removed in 1978 citizen craftsmen and a pronounced unwill to 1979, and the adobe was protected with an ingness on the part of Army officialdom to unamended crest of mud. Some fragments were appropriate sufficient funds for annual main tenance. subsequently treated with chemical consolidants popular at earthen sites administered by the For decades now, the modern caretakers of National Park Service (NPS) at the time. these sites have sought to "preserve" them, using Alarmed by rapid erosion of the adobe at the best technologies of the day. The sites have the site following the removal of the soil-cement been unburied and buried. They have been bricks, the NPS covered the adobe fragments sprayed with waxes, solvents, epoxies, silanes, sili with lime plaster shelter coats in 1988 and 1989. cones, acrylics, and urethanes. They have been With each change in treatment, more historic capped, uncapped, mudded, plastered, and adobe was lost. Although the lime plaster will wrapped. They have been rebuilt, augmented, remain and be maintained, the Fort is developing reinforced, braced, propped, and reroofed. a new preservation guide to shelter the adobe. Perhaps the wonder is not how much adobe is Fort Davis National Historic Site gone, but how much remains at these sites. There were two forts known as Fort Davis. After the forts were abandoned by the army, Deep in the mountains of west Texas are the they served as hardware and building supply cen remains of the second fort, begun in 1867; these ters for the local populations. Quickly, roofing remains have been preserved and in some cases material, floor and ceiling joists, doors and win
56 CRM No 6—1999 reconstructed. Of the four forts, Fort Davis north of Las Cruces. There was only one Fort retains the most intact original adobe structures, Selden and it was composed almost entirely of primarily one- and two-story adobe officers' adobe. quarters. They are full of original plaster and Fort Selden was abandoned in 1878, but it many original wooden features. Two large adobe was reoccupied three years later and reconstruc barracks buildings were reconstructed and today tion began, completed in 1885. In 1891, the serve as the administrative offices, visitor facili troops left Fort Selden again, for the last time. ties, and museum. The site passed into private ownership in 1892, Never truly abandoned, Fort Davis had a and remained so until 1963 when it was donated different fate than the other forts. From the time to the State of New Mexico. In 1974, Fort Selden the army left in 1891 until the site was set aside was declared a New Mexico State Monument. by the federal government in 1961, the fort saw Initial stabilization consisted of clearing away the mixed use by ranchers, local residents, and entre wall falls and fill, and compacting the soil at the preneurs. Not all of its buildings stood roofless wall bases. Most of the walls were initially capped for 70 years, and several were constructed of with urethane-modified adobes, but these were stone masonry. removed two years later because of concern about The Park Service made a bold decision to erosion associated with the caps. Some low reconstruct missing portions of the adobe build eroded walls at Fort Selden were covered with ings that were at least 70% intact and to replace geotextile fabric and covered with fill, an effective missing roofs. Concrete bond beams were technique for preserving these ephemeral frag installed around adobe perimeter walls, and the ments. porches were reconstructed. Exterior plasters were Fort Selden has been the site of an extensive renewed on the structures on officers' row. experimentation in adobe preservation. A test Sheltering the structures with new roofs has wall program—trials of wall coatings, founda slowed deterioration significantly. Consolidating tions, and capping—was begun in 1985, and the chemicals also appeared at Fort Davis, but today Getty Conservation Institute used the site for the unroofed adobe ruins are treated with una consolidation-amended-shelter coat trails begin mended adobe caps and veneers. Some water ning in 1993. For awhile, selected wall fragments repellants are used on modern adobe veneers to were wrapped in aerotextiles to protect them lengthen their life. from rain and wind. Lime piaster Fort Selden State Monument In 1997, New Mexico State Monuments shelter coats over adobe and The site chosen for Fort Selden was on the commissioned a new preservation plan for Fort lime concrete Camino Real de Tierra Adentro, a "royal road" Selden, and it is investigating the options for foundation walls extending from Mexico into its northern colony constructing free-standing shelters over some of of the Cavalry Barracks, Ft. of New Mexico. Fort Selden was established in the ruins. Adobe treatments are now limited to Bowie NHS. 1865 on a bank of the Rio Grande 18 miles unamended shelter coats, and veneer infills and capping with unmodified adobes. Fort Union National Monument Fort Union was the first of the four forts to be set aside as a monument in 1956. Constructed in the 1860s on the windswept high plains of northeastern New Mexico, it was the largest fort in the Southwest. Today it is the largest adobe ruin in the United States. The adobe fort pre served today was the third Fort Union, following the first log fort and a Civil War earthworks. The fort housed not only military troops but also served as a depot and arsenal, warehousing freight and munitions hauled down the Santa Fe Trail, and distributing supplies to other Southwest posts. In the initial stabilization of Fort Union in the late-1950s and early-1960s, soil-cement
CRM No 6—1999 57 intractable, and unbeatable, foe. Properly and continually cared for, adobe buildings can last for centuries. Indeed, there is evidence that the adobe building General Kearny used to make his pronouncement on the Las Vegas plaza more than 150 years ago is still standing. Today it is a music store. Roofless and exposed to the environ ment, however, these buidlings are continually at risk.
Note Dwight Pitcaithley and Jerome Greene, Historic Structure Report, Historic Data Section, The Third Fort Union, 1863-1891, Fort Union National Monument (Denver, Colorado: Denver Service Center, National Park Service, Department of the Interior, 1982), 12.
Non-commis adobe caps were placed on nearly all the walls, Bibliography sioned Officers' and tall unstable walls were braced with internal Cohrs, Timothy and Thomas Caperton. Fort Selden. Quarters, Ft. armatures of iron. Soil-cement adobes were used Santa Fe, New Mexico: Museum of New Mexico Davis National Press, 1993. to rebuild missing corners and fill eroded wall Historic Site. Greene, Jerome. Historic Resource Study, Fort Davis bases. Almost every chemical in the NPS arsenal National Historic Site, Texas. National Park Service, was at one time or another sprayed on a wall at Department of the Interior, 1986. Fort Union, but preservation today relies primar Greene, Jerome. Historic Structure Report, Historic Data ily on unamended mud shelter coats and adobes. Section, Fort Bowie National Historic Site, Arizona. In 1995 Fort Union commissioned a study Denver, Colorado: Denver Service Center, National of adobe deterioration to determine the patterns Park Service, Department of the Interior, 1980. and causes of deterioration and suggest treat Pitcaithley, Dwight and Jerome Greene. Historic Structure Report, Historic Data Section, The Third ments. As a result, most of the walls at Fort Fort Union, 1863-1891, Fort Union National Union were recently recapped with new soil- Monument. Denver, Colorado: Denver Service cement adobes, and certain deteriorating archi Center, National Park Service, Department of the tectural features, eroded corners and lintels for Interior, 1982. example, are augmented with unamended adobes Robbins, John. Historic Structure Report, Ruins immediately. Stabilization Architectural Data, Fort Bowie Conclusion National Historic Site, Arizona. Denver, Colorado: Denver Service Center, National Park Service, Following a long flirtation with chemistry Department of the Interior, 1983. (and the romance isn't completely dead) the forts Welsh, Michael. A Special Place, A Sacred Trust: are relying less on chemical solutions and more Preserving the Fort Davis Story. Administrative on compatible materials. Sheltering with mud or History, Fort Davis National Historic Site. Santa lime plaster, or with roofs, and maintaining his Fe, New Mexico: Intermountain Cultural Resource toric plasters where present are the preferred Center, Professional Paper No. 58, 1996. preservation methods. Each fort has a documented history of Robert Hartzler is an exhibit specialist!conservator at Fort Union National Monument, Watrous, New Mexico, preservation and stabilization. By revisiting these responsible for preservation activities at the site. histories, by studying what technologies work and why, and by better understanding the Photos courtesy the author. processes of deterioration of adobe architecture the preservation specialists charged with caring for these important sites are becoming more effi cient and effective. For years these cultural properties have had to make do with fewer resources—both financial and human—than required. Nature is an
58 CRM No 6—1999 Frank G. Matero The Conservation of Plasters in Earthen Archeological Sites
he preservation of architectural building's primary structural system for protec ruins and earthen archeological tion, decoration, and meaning. These materials, sites presents complex problems generally applied as one or more thin and contin of conservation, interpretation, uous layers, protect a building by concealing its and managementT . Because of the tremendous dif structural core and its vulnerable construction ficulties and limitations in stabilizing such frag joints. As continuous skins, plasters generally mented and exposed sites, remaining original fab provide protection and a reduced surface area to ric must be given maximum protection, and water intrusion, mechanical abrasion, and biolog implemented contemporary preservation stan ical attack. If damaged or failed, plasters and dards must be thoroughly documented. Sites stuccos are more easily repaired or replaced than open to the public must meet these requirements is the structural core. while providing interpretation that is both sensi All plasters exhibit certain properties in tive to their long-term preservation as well as their wet and cured states, and these properties comprehensible to the visitor. Satisfying these allow them to perform successfully as protective requirements is difficult in any ruin site and in skins. At the very least, plasters must possess particular those with fragile materials such as good plasticity and adhesion in the wet state and earthen walls and plasters, which are best under low shrinkage and a hard durable surface after stood in context but are highly susceptible to cure. Specific environmental conditions or use deterioration from exposure and weathering. The impose other requirements such as resistance to many diverse prehistoric and historic sites in the moisture, heat, or abrasion. As an integral com American Southwest offer a unique opportunity ponent of the entire construction system, a plas to consider the problem of the preservation of ter's formulation, application, and use are depen architectural plasters within earthen and masonry dent on its composition and chemical and ruins.1 mechanical compatibility with its structural sup Plasters as Architectural Materials port. This often produces specific systems of Regardless of their appearance, composi installation, keying, or the addition of various tion, application method, and use, all plasters, organic additives such as animal hair, plant fiber, Cliff Palace, Mesa Verde stuccos, and renders may be characterized as sec gums, oils, and resins. Because plasters require National Park. ondary non- structural components applied to a large and exact amounts of water for adequate preparation and because their successful drying or cure is often affected by ambient conditions of temperature and humidity, plastering as an activ ity is often determined by optimal seasonal or environmental conditions. Other factors affecting plaster's manufacture and use include the avail ability of raw materials and sources of fuel for calcining. Plaster occurrence, type, and frequency of application can connote important archeological information about past technical knowledge and attitudes toward space and its differentiation. Moreover, the presence of specific components that determine physical appearance or perfor mance can be useful indicators for identifying cultural values be they aesthetic, utilitarian, or
CRM No 6—1999 59 symbolic. For exam tion and display indoors, preservation and inter ple, the selection and pretation in situ is ideologically the preferred use of certain binders solution, even if reburial or sheltering are the or aggregates for only options. In situ conservation of architectural color, texture, plastic plasters ensures future study of the entire resource ity, low shrinkage, and allows visitors an opportunity to understand and early or damp set the ruin as a once-complete structure. Finishes of all suggest a level of surviving plasters often assist in site interpreta sophistication in tion because they define interior and exterior keeping with other spaces and make tangible and present on a technological achieve human scale what otherwise might be incompre ments. hensible. As skins, plaster In situ preservation of extant plasters within surfaces are suscepti ruin sites has received limited attention due to ble to the elusive evi earlier preferences for the removal of choice deco dences of building use rated fragments and the neglect of more common and alteration that architectural remains. This inattention is proba might not be readily bly the result of a bias toward plaster s ephemeral discernible in a build nature, especially as compared with other more ing's structural ele durable materials, coupled with a dearth of Architectural fin ments. Such ephemeral information—detected research on practical site conservation techniques. ishes on the on these fragile surfaces as wear, profile ghosts of Published research and field work on in situ plas Speaker Chief architectural details, and other marks—makes ter treatments are limited and have focused Tower in Cliff Palace, Mesa them remarkably subtle indicators of past human largely on lime plasters; little attention has been Verde National activity. given to earthen plasters as well as to lime, gyp Park. Preservation Issues sum, or earthen plasters on earthen supports such Whether used externally or internally, plas as adobe, rammed earth, ana jacal. Moreover, ters generally function as intentional or defacto treatment studies have tended to focus specifi temporary materials that were periodically and cally on materials and techniques for consolida sometimes regularly removed or reapplied. tion and not on surface finishes. Despite the Maintenance of this protective skin is tanta widespread observation of and many reports on mount for protection of the entire architectural the detachment and loss of historic plasters from structure as well as for aesthetic conformity. In a earthen and masonry walls, almost no research on preservation context, these functional require reattachment methods has been published. A ments and traditional approaches to maintenance major research program on this subject was initi are often difficult to satisfy since after years of ated in 1991 by the University of Pennsylvania's weathering the plaster surfaces often no longer Architectural Conservation Laboratory of the function effectively as well-integrated and contin Graduate Program in Historic Preservation with uous protective coverings. As a result, these mate the Intermountain Region-Santa Fe Support rials are generally removed and replaced, often Office of the National Park Service. This pro without sufficient documentation or analysis. If gram is directed toward the research, design, and replacement materials less compatible with the implementation of techniques to record, charac structural support or existing plasters are used, terize, test, and treat historic and prehistoric plas the result is often unsatisfactory. Unlike inhabited ters at ruin sites in the American Southwest. sites, archeological sites whose structures are Preservation Strategy incomplete and whose materials are exposed in Plasters often represent a large percentage of ways never intended (unroofed or fragmented) or the architectural finds still in situ at archeological in new unstable environments (after excavation) sites. Their ephemeral nature (especially when present a particularly difficult problem. In these compared with stone or brick) and poor frag situations, remaining plasters will almost always mentary condition necessitate the development deteriorate rapidly or catastrophically. of a phased preservation strategy that allows for Despite the earlier practice of complete or efficient and immediate documentation, stabi selective removal of decorated and painted plas lization, interpretation, and maintenance of these ters from ruins and archeological sites for protec finds.
60 CRMN06—1999 Documentation be accurately diagnosed by professional conserva Documentation of plasters should provide tors. as complete a record as possible of the physical Priority should always be given to intact evidence, including fragment location in plan surfaces and finish layers because features such as and elevation; support material(s), construction tooling, painted decoration, and wear marks techniques including mechanical keying; number often carry much information. In areas where the of layers and their thickness, color, texture, and finish layer is lost and the intermediate or base composition (all verified with laboratory exami layers are exposed, preservation is always recom nation and analysis); application methods and mended although it may be discretionary. In work sequence; existence of secondary finishes areas where a complete loss of plaster has (paints, incisions, relief, etc.); existing conditions occurred, additional problems may arise due to (including environmental); and any subsequent the instability of isolated non-supported frag alterations or treatments. The specific methods of ments or the deterioration of the structural core survey and documentation will depend on avail resulting from the loss of the protective plaster; able funds, time, and expertise, and the level of such is the case with water-sensitive adobe. recording should be commensurate with the sig Stabilization measures may range from simple nificance of the site and the finds. A standard lex protective coverings to complex reburial, or they icon of terms, including those describing condi may involve temporary emergency facing treat tions, should be established and used for long- ments until full-scale conservation can be imple term assessment and multi-site comparison.^ mented. Detachment is a common problem Stabilization affecting many site plasters, especially those of or The most important goal of any archeologi- on earthen materials. During the past eight years, cal plaster stabilization effort should be the mini detached plaster has been treated successfully by mal treatment necessary to insure the preserva using moderate strength, low viscosity grouts of tion of the physical fabric so its informational moderately hydraulic lime, fine sand, and value remains unimpaired for future study and ceramic microspheres. interpretation. Depending on the conditions of Interpretation the plasters, their support, or the environment, The goal of interpretation is to offer a clear stabilization may take the form of temporary explanation of a site and its elements in their Kiva "C" fin emergency work (often necessary after excava fragmented state. While this has sometimes been ishes, Mug tion) or long-term remedial treatment, such as House, Mesa viewed as an opportunity for reconstruction, or consolidation and reattachment. Because rates of Verde National "consolidation" as it is sometimes termed in Park. change (that is, deterioration) are a critical aspect archeological parlance, the process is most suc concerning the rele cessful when the intervention to the fabric is vance and efficacy of minimal and supporting materials deciphering any intervention, every the physical remains and enhancing the visitor's effort should be made to record and identify the understanding of the site are provided. In the causes and mechanisms case of plasters, effective site solutions that both of deterioration before stabilize and emphasize surviving fragments and treatment. Unlike other their architectural context without requiring the integral materials, such removal or replication of entire finishes can be as stone or brick, plas designed. ters are particularly sus Maintenance ceptible to catastrophic Most, if not all, conservation treatments are failure from subtle con temporary in that they require monitoring, main ditions such as blind tenance, and usually eventual re-application. detachment, which While modern conservation principles demand leads to collapse and treatments to be executed with stable materials complete loss. As such and in a manner that allows for re-treatment in their present and antici the future, it would be incorrect to think that pated conditions must many necessary stabilization techniques, such as consolidation or grouting, regardless of the mate rials used, are in fact reversible or allow for com plete re-treatment. Therefore, every effort should
CRM No 6—1999 61 Condition ing capping, grouting, and consolidation. These assessment of practices have been employed at many sites architectural fin ishes, Mug around the world with varying degrees of success. House, Mesa Their selection, however, must be based on Verde National a careful consideration of the site's significance, Park. present materials and building systems, environ mental and human factors, maintenance, and treatment predictability. Low pressure injection grouting with a mixture based on a moderately hydraulic lime, ceramic microspheres, and fine silica sand offers an effective method of reattach ment and meets the essential performance criteria of injectability with low viscosity, reasonable set ting time, minimal shrinkage and weight, maxi mal stability, adequate adhesive bond strength, and good water vapor transmission. Furthermore, using hydraulic lime as a single component bind ing material is advantageous because it is cost effective, readily available, chemically compatible, and easy to use. These techniques have been used for plain and decorated mud and lime plasters on a variety of earthen and masonry structures at historic and prehistoric sites in the American Southwest. be made to employ techniques that best balance Notes preservation needs with the anticipated require 1 The most complete source on the development and ments of future studies and the maintenance of standardization of stabilization techniques for ruin the materials and the site. Although most conser sites in the American Southwest is R. V. Richert and vation research has focused on long-term treat R. G. Vivian, Ruins Stabilization in the Southwestern ment solutions, effective preservation can often United States (Washington, D.C.: National Park be achieved by opting for indirect protection pro Service, 1974). Plaster stabilization, however, is not addressed in this text. vided by shelters or reburial, or by selecting 2 Both historical and current terminology is imprecise directly applied prophylactic techniques, such as on the exact meanings of and distinction between water repellents, and sacrificial shelter coats, these terms. The term plaster is used here to mean which offer easy renewable protection options any inorganic binder (such as clay, lime, gypsum, but with a higher replacement cycle due to their natural or artificial cement) used alone or in combi lower durability. Only through on-site compara nation with aggregates that when mixed with a suit tive monitoring can such methods be evaluated able amount of water forms a plastic mass. When this plastic mass is applied to an interior or exterior in contrast to other solutions designed to be surface, it adheres to it and subsequently sets or long-term. hardens, preserving in a rigid state the form ot tex Conclusions ture imposed during the period of plasticity. Developing an effective preservation strat ' A comprehensive three-part graphic documentation egy that is conservative yet responsive to the program for the Southwest has been proposed by existing and varied contexts of any ruin site and the Intermountain Region Cultural Resources takes into account the ephemeral nature of sur Management Program (NPS) for historic and pre viving building materials (such as adobe and plas historic sites and structures. ter), the vulnerability of the ruin's condition, and Frank G Matero is Associate Professor of Architecture the increasing demands for public interpretation and Chairman of the Graduate Program in Historic is a difficult task. Past and current preservation Preservation at the University of Pennsylvania. practices include replacement; encapsulation with nonhistoric veneers; protective shelters and rebur Photos courtesy the author. ial; and remedial conservation treatments includ
62 CRM No 6—1999 Todd R. Metzger or groupings of related structures that are in a "ruined" state; have exposed intact fabric (e.g., earthen, stone, wood); are not being used for their original function(s); have experienced occu Vanishing Treasures pation^) and utilization(s) that have been inter rupted or discontinued for extended periods of A Legacy in Ruins time; are located in the arid West; and are the resources or part of the resources for which the park was created (or, if National Historic Buildings made of the stuff of earth itself... as Landmarks, are either listed on or are eligible for old as time and human labor, the containers of listing on the National Register of Historic the experience of community, ours in trust.... Places). Examples include architectural remains Now there is an undeniable crisis of care. And wetha t have intact historic fabric exposed at or need your help. above grade (e.g., wall alignments, upright slabs, Roger Kennedy foundations, bins, cists, constructed hearths); Former Director, National Park Service subgrade architecture exposed through excavation or erosion (e.g., pithouses, dugouts, cists); Native American architectural structures (e.g., pueblos, fter 20 years of inadequate fund cliff dwellings, hogans, wickiups, ramadas, cor ing, backlogged treatment needs, rals, earthen architecture); and Euroamerican and a lack of information on architectural structures (e.g., churches, convents, Acondition, thousands of prehis forts, ranch/farm structures, homesteads, mine toric and historic ruins at 38-plus National Park buildings, acequias or related features, kilns). Not Service (NPS) units in the arid West are threat included among Vanishing Treasures resources are ened with severe deterioration and collapse. sites with no exposed architecture or structural These architectural resources—some of them remains (e.g., collapsed, buried, mounded, or World Heritage sites—are important to our otherwise not evident); archeological or other national heritage, and they also hold special and sites with no architectural remains (e.g., lithic significant meanings for a number of traditional scatters, dumps, campsites); Civilian Native American and other communities. In Conservation Corps and Civil Works addition, the NPS employs very few highly Administration buildings and features; historic skilled preservation craftspersons, and many of structures that are regularly maintained and/or them are retiring after 30-plus years in the adaptively used and that fit within Historic Service. A lack of funding has prevented their Structures/List of Classified Structures defini specialized knowledge from being passed on to a tions; structures in use as NPS facilities (e.g., Antelope House new generation of craftspersons. Ruin, Canyon de administrative buildings, trails, bridges, ditches, Chelly National The Program canals); mine shafts and caves without architec- Monument, In 1993, the National Park Service identi Arizona. A large fied and began to correct critical multi-story ancestral preservation weaknesses through puebloan village a grassroots program strongly dating from AD supported by the NPS direc 800 to AD 1275 located in torate and managers that has Canyon del become known as the Vanishing Muerto. The site Treasures Initiative. exhibits numer ous kivas, multi Currently, more than 40 story structures, national parks, monuments, his intact plasters torical parks, historic sites, and decorative paint on walls, memorials, and recreation areas stratified archeo- in Arizona, New Mexico, Utah, logical remains, Colorado, Texas, and Wyoming and numerous rock art images. have identifiable Vanishing Photo by Al Treasures resources. Vanishing Remley. Treasures resources are structures
CRM No 6—1999 63 tural/structural features); pictographs, petro- guidelines for future planning and preservation glyphs, and other rock art (except if found in or will be developed. Adequate funding levels to on architectural structures); and NPS or other achieve specific goals are estimated to be some reconstructed buildings or ruins (e.g., Aztec $67 million—$59 million for emergency preser Ruins' Great Kiva, Aztec, New Mexico, and vation needs and $8 million for the preservation Bent's Old Fort, La Junta, Colorado). (Please workforce. Parks estimate that approximately 65 note that, for purposes of convenience, this arti to 70 technical craftspersons and 50 to 60 arche- cle uses the term "ruins" in full recognition of the ologists or other specialists will need to be fact that some Native American and other com recruited over the next decade (over time, the munities do not use this term because they do boundaries between these two groups will blur, not consider the places to be "ruined," out of use, and a new kind of employee—the preservation or unoccupied.) specialist—will be born). This very rough estima The common thread shared by all tion comes to approximately $1 to $1.5 million, Vanishing Treasures units consists of the ongoing and 3 to 4 new staff for each of the known and degradation of their architectural resources, the potential Vanishing Treasures park units (with continuing and ever-increasing backlog of work actual funding and personnel needs dependent required to bring the condition of the resources upon the size, number, and complexity of the up to a stable and maintainable level, and the resources within each unit). lack of or decline in the availability of qualified In 1993, a Vanishing Treasures: A Legacy in expertise to address current and future needs. At Ruins video was created by concerned NPS man present, most parks are doing only emergency agers—and the work began. work to protect deteriorated infrastructures and stabilize dangerous conditions. Obviously, the Todd R. Metzger is Program Agent of the National Park longer that vitally needed preservation work is Service's Vanishing Treasures Program. put off, the more expensive the final costs are going to be. Vanishing Treasures Initiative administra For more information on the Vanishing tors will create a career development and training Treasures Initiative, contact Todd R. Metzger, program in which skilled craftspersons and other Chief, Division of Resources Management, professionals will have career status, benefits, and National Park Service, Flagstaff Area National career development options analogous to other Monuments, 6400 North Highway 89, segments of the federal workforce, in order to Flagstaff, Arizona 86004; telephone 520-526- ensure work continuity. In addition, a computer 1157, ext. 222; e-mail
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