How does the BlowerDoor test work?
The BlowerDoor test, also known as the differential pressure method, can be used to reliably measure the air tightness of buildings. The measurement is carried out after the windows have been installed and the air tightness level has been completed. By means of a ventilator inserted into an opening in the outer shell (front door or window), an over- or underpressure of 50 Pascal is generated. The air exchange rate is calculated on the basis of the amount of air that is blown in or sucked out. If the air exchange rate is too high, any leaks must be found and repaired. The maximum permissible n50 value (= air exchange rate) is 0.6 h-1 .