Allegheny County Building Footprints (Pennsylvania Spatial Data Access)Footprints for all buildings and out buildings in Allegheny County. Buildings are captured by following the edge of the roof line. All near orthogonal corners are square. Interum roof lines, such as dormers, are not shown. Minor structures such as carports, decks, patios, stairs, etc. which are part of the structure are not shown. Building Footprints were updated as a result of a flyover in 2004. Buildings less than 400 square feet were not captured. Special consideration was given to garages...