The total floor area within the outer faces of the exterior walls of a building defines its overall size. This measurement encompasses all areas within the building, including enclosed spaces such as hallways, lobbies, stairwells, and mechanical rooms. An example includes summing the area of each story in a multi-story building based on its exterior dimensions, inclusive of all interior spaces.
This figure is critical for determining building code compliance, calculating property taxes, and assessing development density. It provides a standardized metric for comparing the size of different buildings and is essential in urban planning and real estate development. Historically, accurate assessment of this metric has facilitated fair taxation and efficient resource allocation within municipalities.