These rolls will list the improvements to a parcel of land, including buildings and, in rural areas, farm implements, livestock, etc. For San Francisco these are unavailable. Water Department Records . The date that utilities were first hooked up to a property is often a good indication of when a building was built. In San Francisco, the water department hook-up records survive back to 1861, and some of these records are now in our library's History Center.
Nothing is more valuable to an architectural historian than original architectural plans.
These often survive for important civic buildings but are much rarer for houses. The City Planning Department has drawings and plans for commercial buildings and large apartment buildings erected after 1906. Their address is 1660 Mission Street. Anyone may view them but only owners or their agents may take copies. Librarians and historical societies should preserve such plans of older buildings whenever possible.