Tudor Place Historic House and Garden stands on 5½-acres of land in the Georgetown neighborhood of Washington, D.C.  In 1805, Thomas Peter and his wife Martha Custis, granddaughter of Martha Washington, purchased the land overlooking the Potomac River.  They asked Dr. William Thornton to design the residence.  Completed in 1816, the house remained under Peter family ownership until 1983 and was listed as a National Historic Landmark in 1960.

Tudor Place has forty-six Aquia Creek sandstone and Indiana limestone windowsills.  Kreilick Conservation, LLC completed conservation of the windowsills as part of Phase II, Stucco Replacement Project, a larger initiative to restore the National Historic Landmark.  To conserve the windowsills, all coatings and incompatible cement patches were removed from the stone.  The weaker sandstone windowsills were then consolidated.  Removal of cement patches and the presence of existing voids necessitated the installation of new, compatible patches using Jahn Masonry Repair Mortar.  The mortar joints surrounding each windowsill were repointed using a lime-based mortar and the windowsills were painted with a mineral-based paint.  Each windowsill was thoroughly documented at each stage of conservation.