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Chronological Listing

Pecos National Historical Park, Pecos, MN

Pecos National Historical Park is quite complex, consisting of multiple historic and cultural features which include Native American ruins, an 18th century catholic church, the western most battle field of the Civil War, and a historic ranch which was once the home of the movie star Greer Garson.  The largest feature, the mission, was constructed of adobe, a historic material used extensively in the arid climate of the American Southwest, but which has fallen into disfavor in recent decades for a variety of reasons including building code, lack of skilled labor, and cost of construction. This project attempts to identify and describe the modes and mechanisms of deterioration of traditional structures and standing architecture and damage thresholds within the mission and convento of Pecos National Historical Park. Vulnerabilities based on factors such as composition, construction, orientation, exposure, past treatment, and maintenance are the primary focus.

Mission San Xavier del Bac, Tucson, AZ2018

The Mission is an iconic regional focal point, nationally and internationally renowned as one of the most impressive and well-preserved examples of Spanish Colonial architecture in the United States. It remains an active Catholic parish, primarily serving the local Tohono O’odham community. Successful management and conservation of a complex site such as San Xavier requires a nuanced understanding of the ways in which the site was and is valued and utilized by different stakeholder groups. This project involves the development of a Conservation Management Plan (CMP) which incorporates the values  these different stakeholders and takes this input into account in the determination of significance, setting out a set of priorities reflective of different user groups that can serve as a principal reference for future decision-making

Quarters 5 and 6, Mesa Verde National Park, Cortez, CO

Mesa Verde’s Administrative Loop is comprised of 15 buildings, including a sub-group of eight residence quarters located on a service road on the western side of the Spruce Tree House Loop. Two of these structures, Quarters 5 (Q5) and Quarters 6 (Q6), were built in the traditional Pueblo Revival style and are within 50 feet of each other, however, they were not constructed at the same time. Q5 was built in 1926 being part of the original building campaign initiated by park superintendent Jesse Nusbaum and his wife Aileen. The sixth residence, Q6,  was erected by members of the Civil Conservation Corp during the CCC years from 1932 to 1942. These building were the first buildings in the park system to reflect the cultural heritage of a region; a concept that would later become a standard approach for the entire National Park Service.The significance of all of these residential structures, as well as their landscape, cannot be overstated as they are an integral part of Nusbaum’s original vision for the park as a whole, which was based on the research that he and his wife did on the architecture and building techniques of the Pueblo peoples of  Arizona and New Mexico.

John Moulton Homestead, Jackson, WY

Commonly known as “the Pink House,” the John Moulton homestead, located in Garand Teton National Park, stands out among the many vernacular log structures in the park for its principle character-defining feature: a pink-painted cement stucco exterior. The principle goal for the CAC was to determine the cause of the cracking in the exterior stucco, as well as the extent of post construction detachment. The hope was that the findings from three methods of non-invasive investigation, Geographic information system (GIS), infrared radiation thermography (IRT) and Structure from Motion (SfM), could help enhance the understanding of the visible phenomena. The success of this experiment hinged on the degree to which these techniques could clarify the evidence of deterioration conditions beyond traditional documentation, ultimately rendering the analysis more robust.

Florissant Fossil Bed National Monument 2017

The Architectural Conservation Laboratory is actively involved in a unique project examining the feasibility of stabilizing large petrified stumps on the Petrified Forest Loop at Florissant Fossil Beds National Monument. These petrified stumps constitute one of the major natural resources of the park. This project focuses on developing site-based methods for the conservation of petrified trees to benefit the park’s mission to conserve its fossil forest.

Fort Union National Monument, Watrous, NM 2016

Established in 1964, Fort Union National Monument is the largest earthen ruin in North America, and commemorates the United States’ expansion of the American frontier during the age of Manifest Destiny. Long rectangular voids in the adobe walls once served as doors and windows. There are no roofs, there is no shelter, these ruins are exposed to the elements all around themThis research developed and tested a framework for the identification and classification of climate-related risks associated with specific masonry and earthen (adobe) built heritage including their context, exposure, materials, construction, previous treatments, maintenance, monitoring, and other critical attributes that affect durability and weathering. The goal was to describe how different manifestations of climate change (e.g., threats) will affect different types of traditional built heritage, especially masonry and adobe ruins. 

Tiffany Mosaic, Woodlawn Cemetery, Bronx, NY


Pit and Quarry, Northampton, PA 2016

The Lehigh Valley’s extractive industries created a much altered landscape with vast and deep quarries, enormous kilns, and mill buildings in a complex landscape that allows for the exploration of architectural, ecological, and socio-cultural considerations.The intent of this project was to produce a well-documented and methodologically driven website that clearly identifies the critical components of this neglected large-scale industrial landscape through one of its principle industries. The Pennsylvania “Slate Belt,” an area of only 22 square miles, lies approximately 50 miles to the northwest of Philadelphia and just south of Blue (Kittanning) Mountain between the Delaware and Lehigh Rivers. The first quarries opened in the 1830s, but significant growth followed in the first decade of the twentieth century when Lehigh Valley accounted for approximately half the slate produced in the United States, eventually becoming the greatest slate producing region in the world.

George Nakashima’s Art Building and Cloister, New Hope, PA 2015

The Arts Building and Cloister occupies a privileged position as the most iconic and architecturally significant of Japanese-American woodworker and architect George Nakashima’s built work. Dedicated on May 7, 1967, the building was intended as space of artistic interchange and contemplation. Of paramount importance is its hyperbolic paraboloid roof expressed in plywood.

Mancos Free Press, Mancos, CO 2015


Jackson Lake Lodge, Jackson, WY 2014

Completed in 1955, Jackson Lake Lodge was designed by architect Gilbert Stanley Underwood. The lodge is an example of the National Park Service’s interpretation of the International Style which became a hallmark of the Mission 66 Program from 1956 to 1966. The lodge combines elements of rustic structures of the earlier decades of the 20th century with a modern design aesthetic that responded to automobile travel.

Tumacácori National Historical Park, Tumacácori, AZ 2014

The Mission San José de Tumacácori is a Spanish Colonial mission now part of the Tumacácori National Historical Park. Federally designated in 1908, Tumacácori was one of the earliest national site dedicated to America's colonial Hispano history. The site is equally important for its long history of preservation and especially its surviving decorative painting on the exterior and interior.

Hovenweep National Monument, Montezuma Creek, UT 2012

Hovenweep National Monument is located in the Four Corners region in a very remote series of canyons on Cajon Mesa. With sweeping horizons and open skies, the large concentrations of freestanding masonry towers are the only interruptions in the southwestern landscape. Holly Tower was constructed around 1200 AD atop a large detached sandstone ledgerock in the center of a deep canyon. It is often considered the most impressive of the Hovenweep structures and one of the best preserved. While the towers have been subjected to multiple stabilization campaigns since the creation of the National Monument in 1923, the condition of the Holly Tower support rock has been largely ignored in previous surveys. Today the support rock’s accelerated erosion threatens the foundation of the tower above, prompting an in-depth study of its decay and treatment.

Bar B C Ranch, Grand Tetons, Jackson, WY 2011

Established in 1912 by Struthers Burt and Horace Carncross, the Bar BC Dude Ranch is the oldest extant dude ranch in Wyoming and possibly in the United States. It is nestled on the flood plain between the Snake River and Teton Park Road. Created by its owners to include cabins, recreational buildings, a pool, corral, and fencing, the site was set up to offer paying customers the opportunity to socialize as well as enjoy the great outdoors.

NAWS, Grand Canyon and Rocky Mountain National Parks 2010

Disaster preparation, response, and recovery characterize the methodology that has come to define the protection of heritage sites from natural and human disasters. Events such as earthquakes, wild land fire, flood, hurricanes, and war are understood as threats or indications of impending danger. Despite the knowledge that disasters present a real threat to many cultural resources,  efforts to prevent or mitigate damage, and reduce risk, even if enacted in advance, are often unpredictable in their short- and long-term efficacy. Recent trends in heritage conservation have focused on risk, danger, and threat as a means to draw attention to the neediest monuments and sites.  This has proven to be especially significant in the growing concern about the effects of climate change and extreme weather such as drought on cultural resources.
This project, developed by the University of Pennsylvania’s Center for Architectural Conservation, and initiated by the Intermountain Region Archaeology Program through the Colorado Plateau Cooperative Ecosystem Studies Unit, developed a recording methodology for a risk assessment plan for selected Native American wooden structures at Rocky Mountain National Park and Grand Canyon National Park. The UPenn team sought to develop a system that established predictable indicators of risk that, when applied to each structure, could suggest which sites might be under threat of collapse.

Western Clay Kiln 7, Helena MT 2010

Brick and tile manufacturing was once ubiquitous throughout much of the United States. Today, however, only a fraction of these industrial complexes survive. Of those standing, few preserve the buildings and machinery, kiln technology, and overall industrial landscape as the Western Clay Manufacturing Company site on the outskirts of Helena, Montana.

Pipespring, Kaibab, AZ 2010

Housing lush springs in the arid Arizona Strip, Pipe Spring has historically been a valuable resource for the Kaibab Paiute Indians and later Mormon pioneers due to its history and location within the evolving Southwest landscape. Since 1923 the site has also served an important role in the National Park Service’s early interpretation of the scenic attractions and historical development of the region.

Durham Castle, Durham England 2009

Farview House, Mesa Verde, Cortez, CO 2009

Since its excavation and stabilization, Far View House has required significant annual maintenance and intermittent large scale remedial stabilization (1934, 1983 and 2005).  In response to past damage and collapse, a new method of capping was explored to preserve wall integrity and reduce the high maintenance cycles associated with cracked wall tops.  Soft “vegetative” capping, utilizing soil, plants, and geosynthetics was installed on a selected test wall and evaluated for its performance by monitoring moisture content, temperature and lateral movement over a period of one year.  The new intervention method was developed as a way to capture and eliminate water before it enters the exposed sandstone and earthen mortar walls, where subsequent damage from salt crystallization and freeze-thaw has been observed over many years.

Gordion, Yassihoyuk, Turkey 2009

As one of the principal archaeological sites in Central Anatolia, Gordion premieres Phrygian architecture that includes a nearly complete monumental 9th century BCE masonry gate, along with the remains of a once impressive citadel. Few sites in the world offer a glimpse of the Late Bronze and Iron Ages in Anatolia.

Wagner Institute, Philadelphia, PA 2009

Whitney Studio, New York, NY 2009

As one of the few surviving examples of the work of artist Robert Winthrop Chanler, the Whitney Studio stands today as a masterpiece of early 20th century decorative art. Located on historic MacDougal Alley in Greenwich Village, the site is positioned at what once was the center of the early modern art movement in America.

Mt. Edgcumbe, Cornwall, England 2008

Rosario Chapel, San Juan, Puerto Rico 2008

Closed to the public for almost a decade due to structural problems, the 16th century Iglesia San José in San Juan, Puerto Rico, was placed on the World Monuments Watch list of 100 Most Endangered Sites in 2004. The church is the oldest surviving masterpiece of Spanish colonial church architecture in Puerto Rico and one of the earliest extant examples of Gothic architecture in the New World began in 1523. Within its walls is the 17th century Capilla del Nuestra Virgen de Rosario, containing the most extensive and possibly earliest murals in Puerto Rico which were once in a serious state of deterioration.

Sprucetree House, Mesa Verde, Cortez, CO 2008

Discovered in 1888, Spruce Tree House is one of the largest and best preserved alcove sites in Mesa Verde National Park. Containing over eighty rooms and seven kivas as well as open areas with very complete surface finishes with geometric embellishments, Spruce Tree House provides a remarkable window onto the region’s Ancestral Puebloan communities of the 13th century AD.

Burial Ground, Southampton,  NY 2007

El Morro, Ramah, NM 2007

Merchants Exchange, Philadelphia, PA 2007

William Strickland’s Philadelphia Merchants’ Exchange Building in Independence National Historical Park is notable for its innovative architectural design including colossal order colonnades with fluted shafts of Pennsylvania marble surmounted by Italian Carrara marble capitals of the Composite order. Ornately carved and signed by their Italian craftsmen, the capitals represent some of the most exceptionally sculpted architectural elements in Philadelphia and the country.

Mt. Edgcumbe, Cornwall, England 2007

New York State Pavilion, Queens, NY 2007

San Antonio Missions, San Antonio, TX 2007

Trinity Cathedral, Pittsburgh, PA 2007

Wagner Institute, Philadelphia, PA 2007

Deschler Morris House, Germantown, PA 2006

Longhouse, Mesa Verde, Cortez, CO 2006

Rosario Chapel, San Juan, Puerto Rico 2006

Strawberry Hill, Twickenham, ENgland 2006

Chiripa-Bolivia 2005

Longhouse, Mesa Verde, Cortez, CO 2005

Strawberry Hill, Twickenham,  England 2005

Burial Ground, Southampton, NY 2004

Frijoles Canyon, Bandelier NM, Los Alamos, NM 2004

Merchants Exchange, Philadelphia, PA 2004

Second Bank of the United States, Philadelphia, PA 2004

The easily accessible Pennsylvania marble quarried just north of Philadelphia was an important regional building stone for public and domestic structures in the nation’s largest colonial city. During the first half of the nineteenth century, William Strickland’s Second Bank of the United States and Merchant’s Exchange were among the first monumental stone structures to showcase the area’s famous marble.

Victoria Mansion, Portland, ME 2004

Orto Botanico, Rome, Italy 2003

San Juan Forts Grafitti, San Juan Puerto Rico 2003

Second Bank of the United States, Philadelphia, PA 2003

Sprucetree House, Mesa Verde, Cortez CO 2003

Tiwanaku, Bolivia 2003

Vizcaya Miami, FL 2003

Vizcaya, built for industrialist James Deering, has survived remarkably intact since its completion in 1922, but unlike the house the gardens have undergone significant changes since their completion the following year. The periodic impact of tropical storms and hurricanes has created ongoing conservation concerns that continue to impact the plantings and the architecture of the gardens.

Capilla Del Santa Cristo, San Juan, Puerto Rico 2002

Orto Botanico, Rome, Italy 2002

Bandelier, Los Alamos NM 2001

Civilian Conservation Corps Buildings 2001

Indian Key, Islamorada, FL 2001

Cliff Palace, Mesa Verde, Cortez CO 2000

Indian Key, Islamorada FL 2000

St Louis 1, New Orleans LA 2000

Trinity Cathedral, Pittsburgh PA 2000

Ayyubid City Wall, Cairo Egypt 1999

Casa Grande, Coolidge AZ 1999

Catalhoyuk, Turkey 1999

Cliff Palace, Mesa Verde, Cortez CO 1999

Drayton Hall, Charleston SC 1999

Drayton Hall
Drayton Hall is well known as one of the earliest and certainly one of the finest examples of Georgian Palladian architecture in the United States. From the time of its construction until the period of the American Civil War, it served as the principle residence and symbolic seat of the descendants of John Drayton, a family of major influence and achievement in the history of the colony and state of South Carolina.

Second Bank of the United States, Philadelphia PA 1999

Casa Grande, Coolidge AZ 1998

Catalhoyuk, Turkey 1998

Chief Tomokie Monument,Tomoka State Park, Daytona Beach FL 1998

Cliff Palace, Mesa Verde, Cortez CO 1998

Coronado State Monument, Albuquerque NM 1998

HABS 1998

Tsankawi, Bandelier, Los Alamos NM 1998

Tsankawi, Bandelier, Los Alamos NM 1998

Casa Grande, Coolidge AZ 1997

Catalhoyuk, Turkey 1997

El Morro, Ramah NM 1997

San Antonio Missions, San Antonio TX 1997

Tsankawi, Bandelier, Los Alamos NM 1997

Adobe Ruins Monitoring, Mesa Verde, Cortez CO 1996

El Morro, Ramah, NM 1996

Mug House, Mesa Verde, Cortez CO 1996

Belmont Mansion, Philadelphia, PA 1995

Casa Grande, Coolidge, AZ 1995

Fort Brockhurst, Gosport, England 1995

Mission San Juan Capistrano, San Juan Capistrano, CA 1995

Mug House, Mesa Verde, Cortez, CO 1995

National Historic Landmarks Database 1995

Second Bank of the United States, Philadelphia, PA 1995

Convent Plaster 1994

El Morro, Ramah, NM 1994

Mug House, Mesa Verde, Cortez, CO 1994

Mug House, Mesa Verde, Cortez, CO 1994

Convent Column San Antonio, TX 1993

El Morro, Ramah NM 1993

Ferrara Italy 1993

Mission San Juan Capistrano, San Juan Capistrano, CA 1993

Ruins/Finishes stabalization 1993

Guggenheim Museum, New York NY 1992

Brooklyn Historical Society, Brooklyn NY 1991

Drayton Hall, Charleston SC 1991

Protestant Cemetery, Rome Italy 1991

Castello Sermonetta, Italy 1990

Center Church Burial Ground, New Haven, CT 1990

Ohio State House, Columbus, OH 1990

Trinity Cathedral, Pittsburgh, PA 1990