The sum of the floor areas of a building included within the outside face of the exterior walls for all stories or areas that have floor surfaces (see CPM 316, “Measurement of Building Areas,” for additional clarification and basis of measurement)
The sum of the enclosed areas in square feet on all floors of a building, including basements, mezzanines, and penthouses of headroom height This does include public circulation elements such as common corridors, stairways, elevator shafts, custodial closets, mechanical equipment rooms and chases, and public restrooms