WINDOW CONSERVATION PROTOTYPE, GEORGIA O'KEEFFE HOME & STUDIO
View of Loewr Bedroom window prior to conservation (Scattergood Design).
The Conservation Study for the Georgia O’Keeffe Home and Studio, completed in 2020, suggested that one of the oversized windows were among the greatest vulnerabilities of the structure. Progressive damage to adobe or wood frames would have serious structural implications for vertical loads from the roof vigas and lateral loads from wind.
Developing an assessment and repair strategy for the large windows was identified as a high priority and, in the spring/summer of 2021, the Museum engaged the Conservation Study team to undertake a pilot project with the assistance of Ed and Jess Crocker of Crocker, Ltd. Support for this project was provided by the Heritage Partnerships Program of the National Park Service.
Work focused on the 20th century window in the north wall of the Lower Bedroom, where cement stucco was removed to examine the conditions of the adobe and wood window framing and to document construction details, supplementing previous investigations. Two layers of cement stucco had been wrapped over the window frame and sill, changing its appearance, preventing the wood from drying and creating a path for water to enter the adobe.
Detail showing overlap of later stucco layers on window sill (Scattergood Design).
Key findings of on-site explorations and laboratory testing were:
A built-up 12” x 27” timber header spans the opening with approximately 16 inches of bearing on the adobe walls and was relatively intact.
A leveling course of formed concrete was placed immediately below the wood sill plate for the window, varying in depth from 4 and 6 inches.
No wood blocking or window frame-to-adobe connections were found at the jambs.
The wood quarter rounds holding the large sheets of plate glass to the wood window frame appear adequate to support the glass at anticipated wind loads.
The team’s goal was to develop new window details that could improve maintenance and performance. The lack of rigid connections between the window frame and adobe was felt to be a positive feature, providing a transition between the adobe, which has high movement due to swelling and shrinkage, and the glass, cannot tolerate movement without cracking. Given the relatively good performance of the adobe/window assembly over seventy years, the team selected a conservation approach of leaving the window sash and frame in place.
Dale Kronkright, Dave Woodham and Tony Crosby undertaking probes (courtesy of Georgia "O’Keeffe Museum).
Interventions completed in the spring of 2022 included:
Using stainless steel screws to improve the connection of the window frame to the wood header.
Inserting wood blocks of a naturally rot-resistant wood into the adobe wall at roughly third points of the jambs.
Installing copper flashing under the sill.
Attaching a new strip of wood on the outer edge of the existing frame to receive the lath and create a recess for sealant.
Tooling the new stucco with a drip edge before it intersects with the head of the window frame, visible here.
The Conservation Assessment and pilot repair program were presented at the Terra 2022 World Conference on Earthen Architectural Heritage in Santa Fe, New Mexico.
