Pressurization, or depressurization, of buildings is a tool to assess the airtightness of building envelopes. A common working pressure is 50 Pa, and the airtightness is expressed in terms of the number of air changes per hour at 50 Pa. To compare buildings of different size a more efficient measure is to define a nondimensional leakage area. We suggest a method to define and calculate the relative leakage area from pressurization data. The method corrects for calibration errors and the effects of aeromotive and buoyancy forces.
This paper describes a set of experiments conducted in a three bedroom house in order to identify the leakage distribution of the building and the air flow rate through the on-purpose designed opening of the interior doors. Starting from the depressurization test in every zone, we were unable to track all the flow equation of every specific identified connection. We therefore propose to characterize the leakage between two zones by a unique general connection. Its flow behavior (K,n) is determined by an optmization under constraints of the results of the various tests.