ISO 9836:1992

In defining area measurement, uses the intra-muros and extra-muros concept. The indicators defined are intended for practical use, as a basis for measuring various aspects of the performance of buildings or as a planning aid. Intended to be used when establishing 1) specifications for the geometric performance of a building and its spaces, 2) technical documentation relating to the performance of whole buildings, 3) evaluation, comparison or control of the properties of a building which are connected to its geometric performance.