Issue 33 – November 2011
A new ISO Standard will help the building industry, real estate sector, and financiers to evaluate better the performance of a building. Performance standards in building – Definition and calculation of area and space indicators ISO 9836:2011 uses the 'intra-muros' concept used in many parts of the world. This refers to indicators of surface and volume in evaluating buildings, which help to evaluate the economic characteristics of a building. The relationship between the area taken up by the building and usable area indicates whether the building costs and materials have been used to their best advantage.
The Standard is intended to be used when establishing:
- specifications for the geometric performance of a building and its spaces (for example, in design, purchasing procedures, and so on, or in building regulations where appropriate)
- technical documentation relating to the performance of whole buildings prepared by designers, contractors, and manufacturers
- the amount of floor area that will not be effectively available for the placement of an individual's workplace, furniture, equipment, or for circulation
- evaluation, comparison, or control of the properties of a building which are connected to its geometric performance.
Area and volume indicators are basic data for calculation and comparison of capital costs and for running costs and maintenance. They give a basis to minimise running costs by Iimiting the amount of space and the cost of individual materials.
The relationship between the area of the building envelope and the usable area shows the extent to which basic savings have been made on the envelope and the running cost of the heating and air conditioning systems. For example, the Standard provides rules for determining the amount of floor area (including attics, terraces, service floor, and storage floors) and volume available for functional use of a building.
The Standard also mentions examples of using building loss factors (the percentage difference between rentable and usable area) when setting requirements for new construction. Some physical elements such as a column or a curve wall where, for example, furniture can't be put, have to be taken into account when fitting out a space.
ISO 9836 will provide a set of rules which can be applied in any country and therefore enable comparability of measurements and will help in calculation of costs and benefits of buildings.