Determination of leakages in the building envelope using pressurization test measurements.

There are several methods by which the airtightness of a building can be measured. One method involves the use of a fan to pressurize or depressurize the building. This creates a known pressure difference across the building envelope. Thecorresponding air flow through the fan is measured and this is an indication of the airtightness of the building. This air flow rate can be expressed as the number of building air changes per hour, a useful unit when comparing buildings of different volumes. So far only simple methods have been employed to analyse this condition. However, it is possible to use a morestrict scientific approach based on mathematical models and known parameter identification methods. These techniques are described in this article.