Mount Vernon's preservation experts answer some of the most frequently asked questions.
From April 1-October 9, 2019, scaffolding covered the west front of George Washington’s Mansion so that Mount Vernon’s preservation staff could undertake restoration work.
While the exterior might appear to be made of stone, it is actually wooden siding that has been worked to achieve the look of stone blocks by first beveling and notching the siding boards (a process called rustication). To make this illusion even more convincing, sand is thrown onto wet paint to create a rough texture like the texture of stone. Luckily, we have letters written by Washington stating exactly why he wanted to coat the house in sand. In one, to White House architect William Thornton, dated October 1, 1799, Washington noted,
Sanding, is designed to answer two purposes—durability, & representation of Stone; for the latter purpose, and in my opinion a desirable one; it is the last operation, by dashing, as long as any will stick, the Sand upon a coat of thick paint. This is the mode I pursued with the painting at [Mount Vernon]…
Mount Vernon’s team of painters worked to remove up to 28 layers of paint and sand. After the paint was stripped, the preservation team closely investigated the siding, mapped the type and material of every single nail, as well as associated nail holes, and looked at remnants of early primer, tool marks, and wood type, with a goal of distinguishing early versus replaced elements. After conducting this work, the team calculated the siding survival rate at just over 83%.
Next, the team of preservation carpenters mobilized to execute wood repairs. Luckily, the siding was in good condition, thanks in part to the sand-casted coating that has provided protection over the years. At the same time, there were some gaps in the siding boards, areas of deterioration, and some earlier wood fills that needed replacing. The solutions were not one-size-fits-all. The different types of repairs ranged from simply re-securing existing elements with screws or nails, to the application of hide glue or hide glue mixed with wood flour (very fine sawdust), to the insertion of small thin wood fills and larger wood blocks secured with adhesives.
The vast majority of repairs were minor in scope, but the pediment over the central door required the most in-depth work. In all cases, the repairs were undertaken with the goal of preserving as much 18th-century building fabric as possible. It was a painstaking process that required much thought and attention to detail. Over the course of the project, and not factoring in shutter repairs, our carpenters completed 644 repairs.
The window sashes were systematically removed by Mount Vernon’s preservation team, working with extreme care to disturb as little of the original material as possible. Depending on the condition of each window, the conservators extracted and analyzed paint samples, stabilized loose joints, conserved panes of glass, reinforced previous repairs, or installed new glazing to form a weather-tight seal. They also documented each window sash in detail. After the work was completed, the windows were reinstalled. This included hanging the first floor sashes with reproduction red-and-white sash cord, replicated from fragments of 18th-century cord found nailed to some sashes.
We believe that all of the windows date to the 18th century; in fact, evidence shows that several of the window sashes had not been removed since their installation, which provided an unparalleled opportunity for study. Most of the glass in the window sashes, however, had been replaced, with only a few exceptions. We hope that more original glass will survive on the east side, where it is protected from the elements by the piazza.
The shutters, which date to the 20th century, were removed and stripped of paint before being assessed and repaired. After repairs, they were repainted and rehung. In addition, many of the pintles (the metal hooks used to hang doors, shutters, or gates) on which the shutters hang had become loose over time. Those pintles were either re-secured to the underlying framing or replaced with reproductions made by Mount Vernon’s blacksmith shop, so that the shutters are held in place more securely.
With the installation of the scaffolding on the cupola, the replica Dove of Peace weathervane was examined. There was a considerable amount of rust and corrosion on the piece, particularly in areas where copper and iron meet. Rust was removed from the surface, it was then carefully sanded down, protective coatings were applied, and then the piece was re-gilded.
After the dove was removed, the 18th-century rod that both supports the dove aloft and acts as lightning protection for the Mansion was examined and treated. After thoroughly cleaning the rod, a rust preventative paint was applied, followed by a protective clear coating. This type of conservation has contributed to the rod’s continued survival. Finally, the team reinstalled Mount Vernon’s iconic dove of peace weathervane.
Mount Vernon’s modern painting and sand-casting process replicates that last used by Washington’s painters in the 18th century, with one exception to account for the shifting, weathering, and repairing that has occurred since 1797. The 18th-century process involved one coat of an oil primer, followed by one thick coat of oil paint. While the final coat of oil paint was still wet, sand was thrown (by hand) at the siding until there was an even application. This year, we followed this process; but, in order to ensure that there was as uniform and level a surface as possible, we applied an additional coat of paint and sand, for a total of two coats. Our layers include: one coat of an oil primer, a first coat of paint and sand, and a second coat of paint and sand. On top of the first coat of paint, after first sifting the sand, we applied only the fine particles of sand to achieve that leveling. Then, on top of the second coat of paint, again after sifting, we applied the mixed particles of sand.
The base paint color will continue to be a creamy white or off-white typical of lead-whites of the 18th century. This color is visible on the window frames, while the siding boards received the coating of sand. The sand is slightly darker than the paint and, as the sand was intended to be the dominant color, it gives the finished surface a warm color evocative of stone. The color is based on laboratory analysis of the early paint and sand on surviving siding boards, as well as Washington’s own words.
Over the next few years, the other sides of the Mansion will undergo the same process of paint removal, assessment, documentation, repair, repainting, and sanding-casting to ensure Washington’s home is preserved for generations to come.Support our ongoing efforts