AIDA

The importance of adventitious air leakage under normal operational conditions and its reduction in order to save energy is highlighted by the relvant building standards of many countries. This operational leakage is often inferred via the measurement of air permeability, a physical property of a building that indicates the resistance of its fabric to airflow. A building’s permeability is the measure of airflow rate through its envelope at a constant pressure differential of 50 Pascals.

The importance of reducing adventitious infiltration in order to save energy is highlighted by the relevant building standards of many countries.  This operational infiltration is often inferred via the measurement of the air leakage rate at a pressure differential of 50 Pascals.  Some building codes, such as the UK’s Standard Assessment Procedure, assume a simple relationship between the air leakage rate and mean infiltration rate during the heating season, the so-called leakage-infiltration ratio, which is scaled to account for the physical and environmental properties of a dwelling.  The