University of Plymouth PEARL https://pearl.plymouth.ac.uk 04 University of Plymouth Research Theses 01 Research Theses Main Collection 2002 THE DEVELOPMENT OF A METHODOLOGY FOR CREATING AN EARTHEN BUILDING INVENTORY FORD, MARGARET LYN http://hdl.handle.net/10026.1/1115 University of Plymouth All content in PEARL is protected by copyright law. Author manuscripts are made available in accordance with publisher policies. Please cite only the published version using the details provided on the item record or document. In the absence of an open licence (e.g. Creative Commons), permissions for further reuse of content should be sought from the publisher or author. This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with its author and that no quotation from the thesis and no information from it may be published without the author's prior consent. il i THE DEVELOPMENT OF A METHODOLOGY FOR CREATING AN EARTHEN BUILDING INVENTORY by MARGARET LYN FORD A thesis submitted to the University of Plymouth in partial fiilfilment for the degree of DOCTOR OF PHILOSOPHY The School of Architecture Faculty of Technology August 2002 ABSTRACT THE DEVELOPMENT OF A METHODOLOGY FOR CREATING AN EARTHEN BUILDING INVENTORY Margaret Lyn Ford This thesis addresses the issue of cataloguing traditional earthen architecture. It proposes a methodology that will permit the systematic collection and analysis of objective and quantifiable data relating to historic earthen, or cob, buildings in a parish in mid Devon. The brief given for this project requhes a multi-disciplinary approach to be taken, one that considers the topographical surroundings and the historic context of the buildings as well as the architectural characteristics. A triangular concept is expounded, with the three elements providing a sound basis for the development of an holistic methodology for creating an earthen building inventory. To comply with the requirements of the brief, a comprehensive review of a wide range of relevant literature is described. Historic and current literature on the use of earth as a constructional material is considered, as well as literature on landscape history and historic documentation. The rationale is that a broad based understanding of the key elements will guide the selection of data for inclusion in the proposed inventory database. Data included in existing methodologies, devised for inventorying historic buildings, is assessed, and the necessity to develop a methodology to manage cob buildings is evaluated. The selection of the study area, the parish of Sandford, in which to demonstrate the proposed methodology, and the collection of the descriptive and the spatial data relating to the cob buildings is explained in detail. The use of a relational database, linked to a Geographical Information System, to collate the collected data and the results achieved fi"om analysis is fiilly described and discussed. The potential use of the methodology as a powerfiil conservation tool, indicated by the results of case studies undertaken, is also considered. The conclusions drawn are that the developed methodology represents the first systematic study on cob buildings inDevon, and that the important results achieved, and discoveries made, present a distinct and significant contribution to the current knowledge of cob buildings in mid Devon. iii CONTENTS Page Chapter One - Introduction to Research Project The brief: 7 The aims 8 The study area 10 Platform for the inventory. 10 Structure of the thesis 11 Chapter Two - Literature Survey Introduction. 13 Literature relating to the global and European use of earth as a buildmg material 14 Literature on the use of earth as a buildmg material m the United Kingdom. 20 Literary references specific to the use of cob as a constructional material 25 Literature relating to landscape 35 Literature relating to historic documentation 48 Conclusions 52 Chapter Three - Recording Methodologies Introduction 54 Recording methodologies world wide 56 Recording methodologies within the United Kingdom. 72 Recording methodologies iised by English Heritage 85 Discussion 97 Conclusions 100 iv r Chapter Four -The Study Area and the Development of The Proposed Recording Methodology using a GIS Introduction- • • 102 Choice of study area ' 103 The cob buildmgs of the study area , 106 The historic context 110 The geology and topography of the study area.. 118 The proposed recording methodology for the cob buildings of Sandford 126 The trial survey. 153 Discussion 156 Conclusions 159 Chapter Five - Examples of Analysis on the Collected Descriptive and Spatial Data using a Geographical Information System IntroductiorL 160 Series of General Analysis , 161 Series 1: Analysis of identification and location data 162 Series 2: Analysis of general characteristics data 165 Series 2a: Analysis of general characteristics data 165 Series 2b: Analysis of constructional characteristics and plan form data. 171 Series 2c: Analysis of architectural details data. 183 Series 3: Analysis of historic context data 187 Series 4: Analysis of the relationships between the Listed cob buildmgs and the surroimding topography and geology 198 Discussion 211 Conclusions 218 r Chapter Six - Application of the Recording Methodology to Twelve Case Studies Introduction • • 220 Part I Case studies of Listed cob buildings 221 Case study one: The Old Forge 222 Case study two: Gaters 224 Case study three: Combe Lancey 227 Case study four: Woolsgrove Farmhouse : 232 Case study five: Ruxford Barton .....237 Case study six: Dowrich House 241 Case study seven: Park House 247 Case study eight: Sandford School 250 Conclusions dravra from the case studies of Listed buildings 253 Part n Case studies of non Listed buildings 254 Case study nine: Aller , 257 Case study ten: Cross 258 Case study eleven: Frogmire 261 Case study twelve: Doggetsbeer 265 Conclusions drawn from the case studies of non Listed buildings 269 Discussion. 270 Conclusions 270 Chater Seven - Conclusions Final conclusions 276 vi Appendices , i 279 Appendix One: Enlargements of Photographs from Figures m main text 280-322 Appendix Two: Documentary material relating to Sandford Parish 323-327 Appendix Three: Table 4.1 Complete database of descriptive data 328-358 Appendix Four: Description of cob building characteristics by century 359-363 Abbreviations 364 Glossaiy 365-369 References 370-387 Publications 388 vii ILLUSTRATIONS Page Figure 1.1 Global examples of earthen buildings 2 Figure 1.2 Devon examples of earthen buildings 4 Figure 1.3 Diagrammatic drawing of a cob house showing stone plinth and horizontal layers, or lifts, of cob walling material 6 Figure 1.4 The Triangular Concept 9 Figure 3.1a Lettelier's figure showing traditional recording techniques 59 Figure 3. lb Lettelier's figure showing digital recording techniques 60 Figure 3.2 Example of Portugese National Monument record 62 Figure 3.3 Recording methodology used for City of Wellington, New Zealand 64 Figure 3.4 Showing examples of earthen buildings in South Island, New Zealand 66 Figure 3.5 An example of an earthen building from the Region Rhones-Alpes inventory 68 Figure 3.6 Showing earthen building included in the Province of Chieti inventory 70 Figure 3.7 Showing the Fletchers Tree of Architecture 76 Figure 3.8 Showing suggested record card devised by Brunskill 78 Figure 3.9 Showing the record form devised by Alcock 80 Figure 3.1 Showing part of a record of Holnicote Estate building 82 Figure 3.11 Showing example of Cox and Thorp's inventory of Kent farm buildings... 84 Figure 3.12 Showing example of a Listed description of a Grade n building 88 Figure 3.13 Showing form used for assessing Buildings at risk 91 viii Figure 3,14 Showing the use of a GIS to create a digital terrain model of a World Heritage Site -98 Figure 4,1 Showing location of study area in mid Devon 104 Figure 4.2 Examples of cob buildings in the Study Area 107 Figure 4,3 Examples of historic maps and plans relatmg to the study area 116 Figure 4.4 Showing the major geological formations in the study area 120 Figure 4.5 Examples of landscape in study area, : 125 Figure 4.6 Illustrates the use of a GIS to analyse differmg variables 128 Figure 4.7 Showing the coverages for the parish boundary, rivers, roads, contours and field boundaries 145 Figure 4.8 Contours in the study area 146 Figure 4.9 Water systems m the study area 146 Figure 4.10 Road systems in the study area 147 Figure 4.11 Field boimdaries in the study area 147 Figure 4.12 Combined topographical themes for study area 148 Figure 4.13 Geological theme for section of study area 148 Figure 4.14 Combined spatial and building themes m study area 149 Figure 4.15 Shows examples of Grade n cob buildmgs in the Trial Survey area and related historic maps 155 Figure 4.16 Showmg elevations, roads, rivers and parish boimdary for part of the study area 158 Figure 5.1 Showing location of Listed cob buildmgs in study area 164 Figure 5.2 Location of Listed cob buildings with jointed cruck roof structures showing those that are also smoke blackened 177 Figure 5.3 Shows decorative mouldings in two sixteenth century buildings 178 ix Figure 5.4 Showmg archaeological sites included m the Devons Sites and Monuments Register ...190 Figure 5.5 Shows sites of buildings for which there is documentary evidence prior to the 19* century 194 Figure 5.6 Showing relationship between selected cob buildings and the contours and water systems 200 Figure 5.7 Showing siting of Ruxford Barton 203 Figure 5.8 Showmg siting of Woolsgrove and Higher Furzeland .204 Figure 5.9 Shows relationship of Listed cob buildings to historic routes 205 Figure 5.10 Showing field boundaries and orchards close to Listed cob buildings 207 Figure 5.11 Compares current field boundaries at Dowrich with those on the tithe map of 1839 209 Figure 5.12 Showmg relationship between pre 1800 Listed cob buildmgs and the sohd and drift geology in part of the study area.