To date, building norms in most countries have traditionally been of a prescriptive nature (establishing accepted procedure or technical guides). Such prescriptive codes can work as an impediment to innovation and to technological development and can pose technical barriers, so they are not acceptable in the international context.

Accordingly, as an alternative to prescriptive codes, what is needed is an approach based on the concept of performance or objectives, in which objectives and the means of achieving them are clearly stated, without implying an obligation to use particular procedures or solutions.

Performance means the objectively identifiable qualitative or quantitative characteristics of the building which help determine its aptitude to fulfil the different functions for which it was designed.