Architectural gilding, which also has long standing historic roots, can been seen on the exteriors and the interiors of churches and governmental buildings. Often times, architectural gilding can be found in lobbies and public spaces of commercial buildings such as hotels and corporate head quarters. While most Architectural Gilding is uses mordant (oil gilding) methods some interior installations require the use of water gilding and even glass gilding applications. Exterior Architectural gilding installations are only done with mordant gilding methods and commonly require very intensive surface preparation of restoration prior to any leaf being applied.