Infrared Thermography to Evaluate Guastavino Vaulting at the West Side Market

INFRARED THERMOGRAPHY TO EVALUATE GUASTAVINO VAULTING AT THE WEST SIDE MARKET

A thesis submitted to the Kent State University Honors College in partial fulfillment of the requirements for General Honors

Catalina Estrada

May 2013

Thesis written by

Catalina Estrada

Approved by

______, Advisor

______, Dean, College of Architecture

Accepted by

______, Dean, Honors College

TABLE OF CONTENTS

LIST OF FIGURES………………………………………………………………………iv

ACKNOWLEDGEMENTS....…………………………………………………………….v

CHAPTER I: INTRODUCTION………………………………………………………….1

CHAPTER II: THERMOGRAPHY AND ITS APPLICATIONS…………………...…...2

CHAPTER III: THE HISTORY OF GUASTAVINO VAULTING……………………...8

CHAPTER IV: THE WEST SIDE MARKET…………………………………………...16

CHAPTER V: FIELD STUDY WITH PASSIVER THERMOGRAPHY AT THE WEST

SIDE MARKET………………………………………………………………………...21

CHAPTER VI: CONCLUSIONS GATHERED FROM DATA………………………...32

WORKS CITED…………………………………………………………………………34

APPENDIX OF IMAGES.....……………………………………………………………35

iii

LIST OF FIGURES

Figure 1.1- Archives of Civil and Mechanical Engineering, “sciencedirect.com.” Last modified 2012. Accessed

March 12, 2013.

Figure 1.2- Maldague, Xavier. Theory and Practice of Infrared Technology for Nondestructive Testing. New York

City: John Wiley & Sons, Inc., 2001, 154.

Figure 2.1- Ochsendorf, John. Guastavino Vaulting: The Art of Structural Tile. New York City: Princeton

Architectural Press, 2010, 55.

Figure 2.2- Tarrago, Salvador. Guastavino Co.: Catalogue of Works in Catalonia and America . Barcelona: Collegi d’Arquitectes de Catalunya, 2002, 107.

Figure 2.3- Ochsendorf, Guastavino Vaulting, 127.

Figure 2.4- Ibid., 147.

Figure 2.5- Ibid., 116.

Figure 3.1- Twist Creative Inc., “Reacquainting a City with its Public Market.” Last modified 2013. Accessed

March 12, 2013. http://www.twist-creative.com/portfolio/west-side-market/.

Figure 3.2- Tarrago, Guastavino Co., 78.

ACKNOWLEDGEMENTS

I would like to thank those who supported me throughout this endeavor. To the

Honors College, for allowing me this opportunity. To Dr. Robison, my thesis advisor, for his ability to stir my thoughts and interests in the matter. To my defense committee, for giving me valuable critiques and pushing me closer towards excellence. To my friends and classmates, who encouraged me to persevere whenever I had any doubts. To my family members, who always believe in me and support me in whatever work I choose to undertake. To my mother, who helps me to be a strong woman. To my father, who taught me that “only the busy have time.”

You were all right, and without you I wouldn’t be where I am today.

Thank you,

Catalina Estrada

CHAPTER I: INTRODUCTION

Infrared thermography is a promising technique for evaluating Guastavino vaulting for the presence of voids and other anomalies. The West Side Market in

Cleveland, Ohio will be used as a test case. The current methods used for evaluating

Guastavino vaulting involve tapping the surface with hammers and listening for voids.

This method is time-consuming and costly. The use of an infrared thermal (IRT) camera to evaluate a Guastavino vault would be quick and inexpensive in comparison to the current expenses necessary to evaluate vaulting. While the scope of this thesis does not permit following up the IRT camera evaluation with a hands-on evaluation of the vault, this thesis aims to demonstrate the ability of IRT imaging to locate anomalies in a tile vault, and provide the incentive to apply potentially cost saving evaluation procedures to

Guastavino vaulting in the future. A FLIR T-620 infrared camera will be used to thermally image the vault. Anomalies found in the post-processing of the images will be analyzed and discussed, identifying possible and likely causes for the observed hot or cold spots in the vault.

Through a better understanding of thermography and the pushing of its boundaries, this thesis will evaluate the use of infrared imaging in order to demonstrate its promise to be a time-efficient and cost-efficient way to check for anomalies in

Guastavino vaulting.

CHAPTER II: THERMOGRAPHY AND ITS APPLICATIONS

The first quantification of temperature was accomplished by Galileo in the year

1593, with the invention of the first glass thermometer. 1 At the time of this invention, however, the science of temperature was not completely understood. It would take a couple centuries before the science was better comprehended. Infrared rays were discovered by William Herschel in the year 1800, when he used a prism to protect his eyes while observing the sun, after having accidentally discovering the planet Uranus.

After this discovery, the doors opened for an array of studies and discoveries in this field, allowing for a greater understanding of temperature.2

Thermography is the study of temperature distribution and is used as a nondestructive testing method in the analysis of buildings and electromechanical systems.

The science of infrared imaging is used to check the thermal qualities of specific surfaces during the performance of building diagnostics.3 By observing the surface temperatures of building elements subjected to a heat flux, internal structures of the elements can be revealed in the surface temperature pattern.

1. Maldague, Xavier. Theory and Practice of Infrared Technology for Nondestructive Testing. New York City: John Wiley & Sons, Inc., 2001, 4-11.

2. Maldague, Theory, 4-11.

3. Ibid., 1.

There are several different thermography procedures that can be applied to buildings. They include passive methods and active methods

(Fig. 1.1). Passive methods use the first law of thermodynamics in conjunction with the collection of temperature Figure 1.1 Diagram of passive versus active differentials across a surface. Heating thermography sources are ambient sources, such as sunlight, or building heating and cooling cycles.

Active methods apply energy to the surface being tested in order to capture more drastic temperature differentiations. The energy being directed at the surface can differ in the length of the pulse when using active thermography. The temperature field can also be recorded based on the variance of time between the input and the output of energy.

Another form of active thermography is vibrothermography, which induces mechanical vibrations to the surface through direct contact, and measures the heat being released at defective locations in the material.4

Given the size of the West Side Market, using active thermography techniques where heat is applied to the building is not a practical means of evaluating the Guastavino vaulting in the West Side Market. Passive thermography will be the more practical technique in order to gather information on temperature differentials of the vault without

4. Ibid., 1-3.

having to directly access the surface. 5 Instead of relying upon the direct application of heat or energy as done in active thermography, the building heating system will be the source of the heat flux, as the exterior temperatures in the 20°’s and 30°’s create a strong temperature flux through the vault to the cold attic above. These surface temperatures on the vault which result from the temperature differential between the conditioned space and the attic will then be analyzed to determine where there are air leaks in the ceiling, where delaminations between tile layers impede the heat flux, and where moisture infiltration causes cooling of the surface through evaporation.

Passive thermography deals with locating hot spots on an object or material. Hot spots are the ∆T’s, or temperature differences, that are picked up by the infrared camera.

These hotspots are generally a few degrees off from the surrounding temperatures.

Passive thermography methods are typically considered to be of a qualitative nature, since it is usually used to locate abnormalities in an object or surface, but the use of passive thermography to locate temperature differentials on the ceiling of the West Side

Market will be a quantitative study as well.6 By scanning the vault of the West Side

Market in varying conditions, it is eventually hoped to develop practical guidelines for obtaining the optimal information from IRT scans of tile vaults.

5. Rosina, Elisabetta, and Elwin C. Robison. “Applying Infrared Thermography to Historic Wood-Framed Buildings in North America.” APT Bulletin. 33. no. 4 (2002), 38.

6. Maldague, Theory, 1.

There are three main benefits of using infrared technology. The first is that surface temperatures are denoted based on the actual temperature that the surface is experiencing at that exact moment. The second is that infrared images can be taken from a distance without the need of scaffolding. The third benefit is the time-efficiency provided by being able to cover large areas at a time through one image.7

Sometimes the optical science behind thermography can reduce the accurate reading of infrared imaging (Fig. 1.2). Aberrations caused by the type of lens used or the way in which it was used can degrade the image

Figure 1.2 Diagram of a thin lens used in being studied. Spherical aberrations in lenses infrared cameras with curved surfaces are caused when rays both close and far from the optical axis are being focused at different points. Coma aberrations are caused by light passing obliquely through a lens in a comet-like fashion across the optical axis. Astigmatism aberrations are caused by cameras not being able to produce a plane object into a plane image. The edges of the image are blurred when the image is shown on a flat screen due to the curvature of the field. Distortion aberrations may occur when trying to correct or limit spherical aberrations in lens. Vignetting aberrations may occur when the lens aperture is reduced, causing images with darker edges.8 When analyzing an image, aberrations such as these

7. Rosina, Robison, “Applying.” 38.

8. Ibid., 160-161.

should be taken into consideration to better understand what is happening on the surface or material being studied.

Passive thermography has been used in the construction industry for decades. In the 1970’s, as building standards became more developed, thermal loss was studied with infrared cameras. These studies led to advancements in thermal building insulation, which helped to save energy and money in the energy crisis of the time. Since the ‘70’s, the use of infrared imaging on buildings has grown to include moisture detection and historical building analysis and repair.9 Passive thermography will be used to analyze the historical ceiling at the West Side Market to check which areas may warrant further analysis, depending on the characteristics of the anomaly.

The thermal insulation of a wall or roof can be assessed through the use of infrared technology. Holes and weak spots in the insulation can be found at points with a significant ∆T.10 ∆T’s denote a disturbance in the heat flux through the material.

Anomalies interrupting these heat fluxes include voids, delaminations, or an incorrectly done repair.11 What affects the differentiation visible through infrared imaging is the thickness of the material being viewed, the thermal properties of the materials, and the radiation and convection of energy being experienced by the surface.12

The layering of the ceramic tiles in the Guastavino vault is critical to the understanding of heat transfer. If the bonding between the layers of tile has imperfect

9. Ibid., 509-510.

10. Ibid., 515.

11. Rosina, Robison, “Applying.” 38.

12. Ibid., 515.

thermal contact, differences in temperature will be seen through infrared imaging.13 If the differences in temperature found in the West Side Market are significant enough, it can be considered an anomaly in the structure, and potentially the location of delamination in the vault structure.

13. Maldague, Theory, 58-59.

CHAPTER III: THE HISTORY OF GUASTAVINO VAULTING

Vaults have been used in buildings for centuries. Masonry vaults were used by the

Romans and Middle Eastern civilizations, while tile vaults were used in Mediterranean architecture for aesthetic and structural reasons. Advancements in tile vaulting dating as far back as the fourteenth century allowed for a more economical, time efficient alternative to stone vaulting. The entirety of a tile vault is made of layers of thin tiles adhered to one another with mortar. Initial layers are sometimes placed with gypsum plaster. The plaster sets quickly so no support or centering is necessary below the vault as the tiles are placed. Overall, the total thickness of the layers of tile that make up a tiled vault is less than the thickness of a traditional stone or brick vault. Also, the lateral forces coming off of a tile vault are less than a conventional vault due to its lower mass, allowing for less buttressing and thinner walls to support the structure.14

Rafael Guastavino Moreno was a Spanish innovator in the field of vaulting. His career began in Barcelona, in the 1860’s, where he had studied architecture at the Escola

Especial de Mestres d’Obres, but never completed the program to become an architect.

This, however, did not deter or hinder him from becoming one of the masters of architectural aesthetics and structure. Growing up in Catalonia, where the use of tile had been widespread for centuries, he acquired much experience through his apprenticeship

14. Ochsendorf, John. Guastavino Vaulting: The Art of Structural Tile. New York City: Princeton Architectural Press, 2010, 20.

as a master builder.15 His training at the Escola Especial de Mestres d’Obres along with his hands-on experience as a master builder gave him an edge to his more theoretically- trained contemporaries coming out of the Ecole des Beaux-Arts in France. This enabled him to receive many commissions in Catalonia, launching his career as a distinguished professional in the area of vaulting before the age of thirty.16 Guastavino’s expertise in structural innovation in Spain opened doors for him in other European countries as well as in the United States. In 1876, he was invited to the Centennial Exposition located in

Philadelphia to present some of his work. This exposure to other parts of the world, along with larger commissions that came his way, alluded to his impact on the world outside of

Spain.17

In 1881, Guastavino decided to uproot his life in Spain, and transfer his practice to New York City. The sudden decision was due to a combination of his dissatisfaction with his practice in Barcelona, and because of his embarrassment of his failed marriage.

He sailed to New York with his youngest son, also named Rafael, bringing with him a new technology in vaulting to the Americas for the first time in centuries.18 The United

States of the nineteenth century had not had much practice with vaulting, but the demands for Gothic Revival style buildings and fire-proof construction advanced his career in the United States. Due to their lack of education in other methods of fire-

15. Ochsendorf, Guastavino Vaulting, 18-20.

16. Ibid., 25.

17. Ibid., 35.

18. Ibid., 39.

proofing and vaulting, American architects designed structural systems that were very heavy and expensive.19

In Spain, architects had to be trained at specific schools in order to earn the title

“architect.” In the United States at the time, however, no such parameter existed.

Guastavino, despite not having completed his education as an architect in Spain, was able to sign his drawings as “architect” in the United States. Guastavino was finally able to work as an architect, and received many commissions in New York City, in which he implemented the use of tile vaulting. His successful use of tile vaults in his architecture allowed for the shift in 1885 of his career from architect to a vault designer and builder.20

Due to the public’s concern with the danger of fires in buildings, the industry for fire-proofing was booming, in particular during the decades after the

Great Chicago Fire of 1871. This opened the door for Guastavino to step in and Figure 2.1 View from above of the construction of the promote his innovative technique of vaulting in the Boston Public Library structure and aesthetics through the use of his vaults. He filed a total of 24 patents for his technique in construction, gaining him credibility in America as a specialist in the construction of vaults.21

19. Ibid., 42-43.

20. Ibid., 45.

21. Ibid., 47.

His largest and most significant commission to date came in the year 1889, when he was given the opportunity to design his vaults in the Boston Public Library (Fig. 2.1).

This grand success granted him even more recognition nationally, and he was invited two separate times to the Massachusetts Institute of Technology to discuss and educate the audience on his tile vaulting methods. Guastavino’s prominence in the industry allowed for the establishment and growth of his company, the Guastavino Fireproof Construction

Company. His projects extended from New York, to Massachusetts, Colorado, New

Hampshire, Pennsylvania, Rhode Island, and New Jersey. He was able to advertise for and market his “system” through the publicity received from his work in the Boston

Public Library.22

Guastavino’s son, Rafael Guastavino Jr., took over his father’s company since before the death of his father in 1908. Renamed the R. Guastavino Company, it began to face challenges posed by the new aesthetic styles of the 1920’s, when the use of steel and concrete began to be more valued than the ornamental styles of the previous decades.

Although the distinction between father and son is sometimes lost in between the lines of history, Guastavino Jr.’s projects directed the company towards a new direction with new innovations and technologies in the

23 construction industry. Figure 2.2 Image of St. John the Divine used in an advertisement for the R. Guastavino Company

22. Ibid., 48-60.

23. Ibid., 115.

The R. Guastavino Company began to be commissioned larger projects, and even built one of the largest masonry domes in the entire history of architecture, for the

Cathedral of St. John the Divine in New York City (Fig. 2.2). Not only was it one of the largest domes in history, but it was also one of the quickest built and lowest costing domes for its size.24 The company’s system of erecting domes and vaults was proving itself to be a game changer in the history of American architecture. Not only did

Guastavino Jr. make advancements in the structural integrity of the tile domes and vaults, but also augmented the aesthetic quality of his work by creating sophisticated tile patterning. In earlier projects such as the Boston Public Library, less layers of tile were used, leaving exposed some rougher interior finishes. By

1910, the company was using four steps to complete a vault in

the Guastavino style (Fig. 2.3). Figure 2.3 Four-step process of building a Guastavino vault The first layer was erected by the use of the quickly adhering gypsum and rough tiles. A second layer of rough tiles was placed on top of the first with a layer of Portland cement mortar in between the two. A third layer of finished tile was placed below the first layer, also adhered by a layer of Portland cement mortar. Finally, the joints between each

24. Ibid., 121.

finished tile were filled with Portland cement mortar. After these four steps, additional layers of tile could be added to the top of the vault if its structure depended on it.25

On top of all of the Guastavino Company’s successes in structure and aesthetics,

Guastavino Jr.’s interest in acoustics drove the company towards a new area of expertise.

Guastavino Jr. received six patents for his developments in acoustical tiles used in his structures. This breakthrough in the use of tile allowed for the company to expand even further into the American construction industry.26

Although the R. Guastavino Company enjoyed its greatest success in the 1910’s and 1920’s from its new innovations in aesthetics and acoustical qualities, its decline was imminent. The company went from producing almost 900,000 tiles per year in 1915, to a mere 10,000 tiles in 1928 (Fig. 2.4). The company’s decline continued when new construction took a devastating hit from the Great Depression, reducing the demand for the production of tiles for vaults and domes. In addition to the decline in demand for tile construction due to the economic downturn, the company was transforming from a producer of an inexpensive structural solution, to a producer Figure 2.4 Guastavino tile production in the 1900’s of an expensive interior finish.27 The market

25. Ibid., 127.

26. Ibid., 133.

27. Ibid., 147.

that had originally been wide open for a structural system that was quick, cheap, and effective, was not being given the full attention of the R. Guastavino Company. The company had expanded itself beyond this market, to the point where its original intentions of a simple system were lost behind layers of tiles and mortars and high-quality finishes.

Rafael Guastavino Sr. and Jr. earned themselves and their company a place in the history of the “American Renaissance,” which was considered to be the period of 1876-

1917. The desire for historicist buildings flourished in this period, due to their feeling of monumentality and grandeur. Guastavino vaults and domes were even considered “as genuine a piece of constructive design as any of the Roman or medieval works.”28 This level of accolade proved that a Guastavino design was critical for the authenticity and legitimacy of any monument in the American city.29 In this time period, architects sought to give a lasting feeling of significance to their buildings, so the use of a Guastavino-vaulted Figure 2.5 R. Guastavino Co. advertisement depicting several of the company’s greatest ceiling or dome spread across the entire United accomplishments

28. Ibid., 150-151.

29. Ibid., 151.

States (Fig.2.5). Such monuments to craft and technology such as Cleveland’s West Side

Market should be preserved and revered.

CHAPTER IV: THE WEST SIDE MARKET

The West Side Market, located in Cleveland on West 25th Street and Lorain

Avenue, has been in existence long before its present structure was built (Fig. 3.1). In the

1840’s, there was a distinction in municipalities between Cleveland and Ohio City. The land at the intersection of Lorain and West

25th, then known as Pearl Street, was donated by two businessmen to the municipality of Ohio City for the sole purpose of being an open-air market. As the two cities flourished a decade later, Cleveland Figure 3.1 Present-day West Side Market adopted Ohio City as a part of its municipality.30

The Pearl Market, as it was called at the time, was housed under a wood-framed building in the late 1860’s. The boom of the city’s population brought much prosperity to the market, causing it to outgrow its small structure, and requiring a larger space. At the turn of the century, the city of Cleveland purchased a plot of land on the same intersection, directly across the street of the Pearl Market, and called for the design of a new market space.31 W. Dominick Benes and Benjamin Hubbell were the two architects

30. Cleveland Historical, “West Side Market.” Last modified 2013. Accessed March 5, 2013. http://clevelandhistorical.org/items/show/67.

31. Cleveland Historical, “West Side Market.”

responsible for the design of the market.32 They created a 30,000 square foot column-free space that could house 100 vendor stalls.33 In addition to these vendor stalls located within the structure, 85 outdoor produce stalls were also housed.34

The new West Side Market was finally opened to the public in the year 1912.

Since then, the West Side Market has been an icon of Cleveland, being the oldest publicly owned market. Featured on many popular television shows on the Travel

Channel and Food Network, the market attracts tourists all year round. Over a million people from all over the world visit the West Side Market yearly to partake in the unique shopping experience the market provides.35 The culture of the market precedes the age of the building itself, therefore the meaning associated with the West Side Market transcends just the space itself. A building such as this must be protected and preserved in order for it to fulfill its meaning as a symbol of the growth of Cleveland and the sense of community it grants.

The market was listed on the National Register of Historic Places in 1973, and named one of the “10 Great Public Places in America” by the American Planning

Association in 2008. Not only is the West Side Market culturally significant, but architecturally significant as well. A signature clock tower, standing at 137 feet tall, acts as a beacon denoting the location of the market and the arrival to an important space. The

32. The Ohio Historical Society, “Remarkable Ohio.” Last modified 2012. Accessed March 5, 2013. http://www.remarkableohio.org/HistoricalMarker.aspx?historicalMarkerId=106244.

33. Bunnell, Gene. “Great Public Spaces.” American Planning Association. no. December (2008).

34. Cleveland Historical, “West Side Market.”

35. West Side Market, “About the Market.” Last modified 2008. Accessed March 5, 2013. http://www.westsidemarket.org/about.html.

materials range from granite to brick, and the large column-less arcade is supported by a

Guastavino vault.36

The decision to use a Guastavino vault in the West Side Market was a logical one.

During the period of rapid increase in Cleveland’s population, regulations on public spaces were virtually nonexistent. At the end of the 19th century, Cleveland was a rather unsanitary and polluted place to live. When proposals for a new market on West 25th and

Lorain began to emerge, a Market Commission was formed. This commission had been recently inspired by the most recent World’s Columbian Exposition, and wanted to bring some of the new innovations seen there to Cleveland. There was a call for the improvement of sanitary conditions within the city during the turn of the century, and a wanting to improve the quality of the residents’ lives. The Commission hired the architects Hubbell and Benes, who were known for their public works of high quality, to aid in their vision to create a better Cleveland.37

As more attention to sanitary conditions was given, the Market Commission determined that the new market must be build out of completely fireproof material, in comparison to the existing Pearl Market’s wooden construction. The architects, Hubbell and Benes, were not unfamiliar with Guastavino’s work in tile construction, such as the work in the Boston Public Library, so the decision to use such a successful technique of fireproof construction was clear. The architects appreciated the aesthetic quality of the unfinished versus finished tile, and were inspired by this Beaux Arts technique. Hubbell

36. The Ohio Historical Society, “Remarkable Ohio.”

37. DeAngelo, Daniel. “Cleveland’s West Side Market at 100.”Construction History Society of American Conference. no. November (2012), 3-4.

and Benes designed the West Side Market to be almost a completely masonry structure, with a tile ceiling, tile walls, and a tile floor. This allowed the entire interior of the market to be easily cleaned, as the concern for sanitary conditions in the marketplace was high, as well as completely resistant to fire, another requirement set up by the Market

Commission.38

The structure of the ceiling is composed of five steel arches that span across the space and Guastavino tile vaults in each bay. The design of the ceiling was done by the

R. Guastavino Company, proving the Market Commission’s dedication to providing an aesthetically pleasing and long lasting for its vendors and shoppers (Fig. 3.2). The

Guastavino method for constructing this space permitted Hubbell and Benes to create a grand, large-scale food hall for the West Side Market in an affordable way. The thinness of the tile vault paired with the requirement for less material on the bearing walls which needed to support less weight laterally than for that of a regular vault, exemplified the cost-efficiency and the structural integrity of the Guastavino tile vault Figure 3.2 Image used by R. Guastavino Co. as advertisement for large-span spaces system.39

38. DeAngelo, “Cleveland’s,” 5.

39. Ibid., 5-6.

The overall dimensions of the herringbone-patterned Guastavino vault are vast in comparison to the surrounding narrow streets and the smaller scale buildings. The market hall is 124 feet by 241 feet, with the height of the vault reaching 44 feet, and the proportions of the market in plan are almost 2 to 1. The market becomes a basilica-like space, emphasizing its importance and prominence as an icon of the city of Cleveland.

The soaring ceiling overhead creates not just the space, but the experience of the marketplace, and elevates it from simply a banal act of grocery shopping to a cultural and traditional experience.40

The West Side Market has seen the quick rise as well as the steady decline of

Cleveland over the past 100 years. However, Cleveland has begun to experience a renaissance of its own. The countless television programs featuring the West Side Market have brought much attention to the area, and the Ohio City neighborhood has become a new hotspot for food, drinks, and fine dining. The area is going through a rebirth; one that may have never happened if it was not for the West Side Market. The significance of the market throughout history requires that it continues to be maintained and preserved.

Techniques of building analysis such as passive thermography can be applied to explore the condition of the market, in particular, its Guastavino vault.

40. Ibid., 6-7.

CHAPTER V: FIELD STUDY WITH PASSIVE THERMOGRAPHY AT THE WEST

SIDE MARKET

In order to preserve a historic building such as the West Side Market, its vault needs to be maintained. This thesis will test the applicability of thermography in order to demonstrate a safer, more cost-efficient way to check for potential delaminations, air leaks, and water infiltration in the Guastavino-vaulted ceiling in the West Side Market.

Currently, the methods of testing for delaminations are limited to engineers and technicians standing on scaffolding to reach the ceiling in order to sound the vault surface with hammers. However, this can be costly due to the man-hours needed and due to the cost of scaffolding. By using an infrared camera, however, work is conducted remotely from the ground. The infrared camera picks up degree differences to the tenth decimal, therefore showing points in the ceiling where there is a temperature change.

Thermography can quickly point engineers to likely areas of problems, significantly reducing survey time.

The field study at the West Side Market was conducted on two different days and times with different ambient temperatures. Thermal images of the ceiling were taken with a FLIR T-620 model infrared camera. They have been analyzed to find locations on the ceilings where there is a significant thermal discrepancy. This study intends to show that thermography is an effective tool for locating anomalies in the Guastavino vaulting when 22

a significant heat flux is present. Each image and its analysis will refer to the reflected ceiling plan seen below of the seven bays of the Guastavino vault.

Interior space of the West Side Market

Reflected ceiling plan of the West Side Market

Documenting the vault with a FLIR T-620 camera

The first day of field work at the West Side Market was the morning of January

8th, at approximately 9:00AM. Images of the ceiling were taken beginning with the southwestern-most bay and in order from the right edge of the bay to the left edge of the bay and numbered accordingly. The temperature inside of the West Side Market was

68°F, while the temperature outside was in the upper 20°’s to mid 30°’s. The windows were closed inside of the market, and the interior lights were on. In the post-processing of the images, the temperature range was modified depending on the image in order to better view certain elements and their thermal qualities.

The second day of field work at the West Side Market was the middle of the day on January 10th, at approximately 1:00PM. Similarly to the previous field study, images of the ceiling were taken beginning with the southwestern-most bay and in order from the right edge of the bay to the left edge of the bay and then numbered accordingly. The temperature inside of the West Side Market was again 68°F, while the exterior temperature was in the mid 40°’s. The windows were closed inside of the market, but this time the interior lights were off. This allowed for the viewing of the light sockets. Also similarly to the first day, the temperature span was modified in post-processing, as required by each individual image in order to see the anomalies. The following images from day 1 and day 2 were selected according to phenomenon, with the additional images from the respective day organized in the appendix of images.

Analysis of Image 1.5:

 hot area dispersing over surrounding tiles  cold spots in between certain tiles  defined line of cold moments in between tiles may indicate a change in mortar

∆T between Sp1 & Sp3 = 0.9°

Hotspots tended to be visible at the corners of the bays. The striations on the backs of the tiles, used for the placement of mortar to adhere one tile to the next, were visible in most of the images. A change in mortar, as speculated above, is called a cold joint. 25

Analysis of Image 1.6:

 area of ceiling more homogenous in temperature  warmer tiles surrounding light fixture

∆T between Sp1 & Sp3 = 0.3°

Images taken of the center of the bays showed a more even surface temperature of the vault. However, the tiles around the light fixture were warmer due to the ceiling lights being turned on.

Analysis of Image 1.16:

 hot area at location of light fixtures  cold area at connection between steel structure and tiled ceiling  relatively even temperatures across tiles  plume of cold area could indicate a moisture leak

∆T between Sp1 & Sp3 = 0.6°

The area in this image with the coldest surface temperature resembles what a plume of moisture looks like. This could indicate a possible instance of moisture leakage in the corner of this bay. 27

Analysis of Image 2.2:

 cold area in the middle of a warmer area  joints of tiles are visibly cooler  relatively even distribution of temperature

∆T between Sp1 & Sp3 = 0.3°

The second day yielded similar results in the centers of the bays. The tiles had an evenly distributed surface temperature, with the joints of the tiles visibly cooler.

Analysis of Image 2.8:

 significantly warmer areas near corner of bay  striation of tiles can be seen  cooler joints around tiles

∆T between Sp1 & Sp3 = 1.1°

Day 2 also demonstrated hotspots at the corners of the bays, with the striations behind the tiles still visible. 29

Analysis of Image 2.9:

 warm areas where light bulbs exist  holes around fixtures visible

∆T between Sp1 & Sp3 = 1.1°

With the ceiling lights off, instances of probably air leaks were visible around the fixtures. Although the lights were off, the light bulbs were still warmer than the areas surrounding them. 30

After the first day of gathering images and temperature data from the Guastavino ceiling, it can be determined that the joints filled with Portland Cement mortar allow for cold air to leak in to the West Side Market space below. Images 1.7 and 1.11 (found in the appendix) demonstrate this very clearly. Also, images 1.5 and 1.14 (appendix) show the striation of the tiles on their backside that helps them adhere better to the Portland

Cement mortar and to the adjacent tiles. In most areas, the temperature across the tiles was rather homogenous; cooler tiles next to the edges of bays with warmer tiles towards the center of the bays. Some exceptions to this such as images 1.1, 1.3, 1.10, 1.14, and

1.15 (appendix) are hot spot anomalies in the ceiling and should be further studied. These warm areas, typically found in the haunch of the vault about 4 tiles away from the vault perimeter, suggest a condition common to all of the vaults. It is theorized that some delamination of the tile vault may occur at this region of greatest tensile and shear stresses. A few intriguing cold spots in areas other than at the joints, such as in images

1.17 and 1.18 (appendix), may indicate moments of thermal bridging in the ceiling.

Images 1.7, 1.10, 1.14, and 1.17 (appendix) had ∆T’s of 1.0° or more, while images 1.5,

1.12, and 1.15 (appendix) had ∆T’s of less than 1.0° but more than 0.8°.

The second day of gathering data from the West Side Market yielded supporting results for day one, in that the light fixture penetrations allow for cold air to leak in to the space below. Cooler joints are evident in almost every image taken on day two, showing that the Portland cement mortar is a better conductor of heat (or cold) than the terracotta tiles. Again, striations were visible in some instances in the tiles, such as in images 2.8 and 2.17 (appendix). It is clear that the thermal properties of the mortar joints and the 31

tiles are different, since there were so many instances where their temperatures differed.

Even within the tile, the moments where the striations decrease the thickness of the tile, the different thermal qualities are visible. During day two of data collection, the interior lights of the space were turned off, which provided an interesting opportunity to view the thermal retention of the light fixtures. As seen in images 2.7, 2.9, and 2.12 (appendix), although the light bulbs were not on, they remained warmer than the other surfaces around them. Also, with the lights off, holes in the light fixtures were evident where cool air was entering the building. On day two, ∆T’s were much greater than on day one. This could be due to the hour of the day in which the images were taken. By the time the field study was conducted, the sun had much more time to warm the ceiling than on day one.

The study on day one was conducted in the morning, when the sun perhaps had not had enough time to warm the ceiling to a point where anomalies would be more apparent. The images with the largest ∆T’s (over 1.0°) were 2.4, 2.6, 2.8, 2.9, 2.10, 2.11, 2.12, 2.15, and

2.16 (appendix). Of these, the largest ∆T was that of image 2.11, with a difference of

4.2°. In these images, hot spot anomalies can be seen in 2.3, 2.6, 2.8, 2.10, and 2.11

(appendix). These images show sudden hot areas that quickly become cooler over the course of a few tiles.

CHAPTER VI: CONCLUSIONS GATHERED FROM DATA

After gathering data from two different days and analyzing each image, speculations on what the anomalies in the images could mean were made. A consistency of hot spots near the edges of the bays was found, while the centers of the bays were consistently homogenous in temperature distribution. This could be due to the tension and shear forces being experienced by the edge of the bays. The haunch of an arch is the point where the greatest tensile and shear forces are experienced; therefore it could be possible that these hot spots are locations where cracking in the mortar located in between the layers of tiles is occurring. This air gap created between the layers acts as an additional layer of insulation, which can create warmer areas in the ceiling. In contrast, the centers of the bays experience more evenly distributed temperatures. The center of an arch is in compression, which can explain why the centers of the bays are not experiencing many moments of cracking mortar visible as hot spots. It seems to be that the tiles and their joints that are in compression are in better shape than the tiles and joints in tension. However, throughout the ceiling there are cooler areas that suggest moments of a good mortar bond. After analyzing the data, it can be speculated that the anomalies near the bays should be further investigated and tested in order to help preserve the Guastavino vault’s magnificence. 33

Imaging on day two produced more detail in the structure of the vault. While increased sunshine in the afternoon would decrease the potential temperature differential between the heated interior and the attic, it is speculated that having the heating system on for many more hours increased the temperature at the vault level, resulting in better imaging.

Works Cited

Bunnell, Gene. "Great Public Spaces." American Planning Association. no. December (2008).

Cleveland Historical, "West Side Market." Last modified 2013. Accessed March 5, 2013.

http://clevelandhistorical.org/items/show/67.

DeAngelo, Daniel. "Cleveland's West Side Market at 100."Construction History Society of American

Conference. no. November (2012).

Maldague, Xavier. Theory and Practice of Infrared Technology for Nondestructive Testing. New York

City: John Wiley & Sons, Inc., 2001.

Ochsendorf, John. Guastavino Vaulting: The Art of Structural Tile. New York City: Princeton Architectural

Press, 2010.

Rosina, Elisabetta, and Elwin C. Robison. “Applying Infrared Thermography to Historic Wood-Framed

Buildings in North America.” APT Bulletin. 33. no. 4 (2002).

The Ohio Historical Society, "Remarkable Ohio." Last modified 2012. Accessed March 5, 2013.

http://www.remarkableohio.org/HistoricalMarker.aspx?historicalMarkerId=106244.

West Side Market, "About the Market." Last modified 2008. Accessed March 5, 2013.

http://www.westsidemarket.org/about.html. 35

APPENDIX OF IMAGES

Analysis of Image 1.1:

 cold areas at the junction of the ceiling and the steel structure in between each bay  large warm area across several tiles  cold moments at the joints  optical image reveals efflorescence indicating a moisture leak occurring along edge of bay

∆T between Sp1 & Sp3 = 0.3°

Analysis of Image 1.2:

 transition of warmer tiles at the top of the image to colder tiles towards the bottom of the image  warm spots in the middle of some tiles

∆T between Sp1 & Sp3 = 0.4°

Analysis of Image 1.3:

 cold next to steel structure  sudden warm area next to cold area  cold moments in between joins  delamination appears to be occurring

∆T between Sp1 & Sp3 = 0.4°

Analysis of Image 1.4:

 warmer areas in the center of some tiles  cold spots in between tiles

∆T between Sp1 & Sp3 = 0.6°

Analysis of Image 1.7:

 clear definition of tiles versus joints  warmer moment next to juncture with steel structure

∆T between Sp1 & Sp3 = 1.3°

Analysis of Image 1.8:

 significantly colder area at corner of bay  tiles with warmer moments in their center and colder moments closer to the joints  stain visible in optical  instance where a new mortar may have been used

∆T between Sp1 & Sp3 = 0.7°

Analysis of Image 1.9:

 warm area near corner of bay  relatively homogenous tile temperature across tiles

∆T between Sp1 & Sp3 = 0.7°

Analysis of Image 1.10:

 isolated hot spot  colder area immediately next to warmer area

∆T between Sp1 & Sp3 = 1.0°

Analysis of Image 1.11:

 very clear definition of tiles versus joints  warm area spreading out towards adjacent tiles

∆T between Sp1 & Sp3 = 0.4°

Analysis of Image 1.12:

 hot spots in corner of bay  cold joints in between

∆T between Sp1 & Sp3 = 0.9°

Analysis of Image 1.13:

 two warm areas with colder areas separating the two  cold tiles next to corner of bay

∆T between Sp1 & Sp3 = 0.4°

Analysis of Image 1.14:

 sporadic hot spots on tiles  uneven temperatures across image

∆T between Sp1 & Sp3 = 1.1°

Analysis of Image 1.15:

 isolated hot spot in corner of bay  cold tiles around warm area

∆T between Sp1 & Sp3 = 0.8°

Analysis of Image 1.17:

 isolated cold spot next to warmer area  cold joints visible

∆T between Sp1 & Sp3 = 1.2°

Analysis of Image 1.18:

 several hot areas  four particular cold spots at top of image next to Sp3

∆T between Sp1 & Sp3 = 0.7°

Analysis of Image 2.1:

 large hot spot near corner of bay  tiles with warmer center and cooler edges near hot spot

∆T between Sp1 & Sp3 = 0.4°

Analysis of Image 2.3:

 sporadic hot spots with cooler areas in between  unique hot spots near the middle area of a bay are moments of interest

∆T between Sp1 & Sp3 = 0.4°

Analysis of Image 2.4:

 large hot area over many tiles  cooler joints in between warmer tiles  discoloration visible in optical is reflected in anomaly seen in infrared image

∆T between Sp1 & Sp3 = 1.6°

Analysis of Image 2.5:

 warmer area decreases in temperature over the course of several tiles  even distribution in center of bay

∆T between Sp1 & Sp3 = 0.7°

Analysis of Image 2.6:

 several particular hot spots on half of a few tiles, seen below point Sp2  instances of distress visible in optical and infrared image, possible water leakage

∆T between Sp1 & Sp3 = 1.6°

Analysis of Image 2.7:

 turned-off light fixture shows visibly warmer areas where the light bulbs are located  some holes can be seen around the light fixtures  air leakage apparent

∆T between Sp1 & Sp3 = 0.5°

Analysis of Image 2.10:

 significant large hot spot in area

∆T between Sp1 & Sp3 = 2.7°

Analysis of Image 2.11:

 hot spot spreads over large area  very large temperature differential

∆T between Sp1 & Sp3 = 4.2°

Analysis of Image 2.12:

 hot spots where bulbs are located and around light fixture  some holes around the fixtures are visible

∆T between Sp1 & Sp3 = 1.1°

Analysis of Image 2.13:

 hot area gets cooler over the course of several tiles  cooler joints can be seen between virtually every tile  cold area in infrared image, visibly affected in optical image could be moisture

∆T between Sp1 & Sp3 = 0.6°

Analysis of Image 2.14:

 large hot area in corner of bay

∆T between Sp1 & Sp3 = 0.8°

Analysis of Image 2.15:

 hot spot gets broken up by cooler areas surrounding it

∆T between Sp1 & Sp3 = 1.4°

Analysis of Image 2.16:

 hot spot near corner of bay  joints can be seen as cooler even within the large hot spot

∆T between Sp1 & Sp3 = 1.9°

Analysis of Image 2.17:

 hot spot broken up by a series of cooler tiles in between

∆T between Sp1 & Sp3 = 0.7°