Definition:
The surface area of all rooms in the building (in view of load-bearing and non-bearing structures) used to meet the needs directly related to the purpose of the building (or - in the case of buildings with several functions - total area of all parts sectioned off, e.g. a clinic, post office, restaurant in trade building). As regards containers, silos and sheds, the usable space of which cannot be stated, the development area of those structures is given, i.e. the area determined by the vertical projection of the outer edges of the structure on the land area.