Passive house standard:
As more and more homes are built in accordance with the passive standard, we as consultants of building physics get more and more requests to perform blowerdoor tests. The passive house concept can be applied in both new construction and renovation of housing and makes a significant contribution to the national and European ambition to save energy, because the EU demands in 2020 residential housing accounts for 20 percent of energy reduction on its behalf. Between inside and outside a pressure difference of 50 Pascal is created to measure the amount of air that is leaking. The air tightness of the facade for a passivhaus is at least 0.6/h at a pressure difference of 50 Pa. This corresponds approximately to 0.142 dm3/s/m2. With a blowerdoor test can be demonstrated whether that value is feasible in the facade of the building. Design and construction of the passive method benefits from proof of quality. A builder must be able to demonstrate that the required air tightness is guaranteed.
Another way to the air-tightness is to display the number of replacements of the air space per hour. When in 1 hour all the air in the room is changed, there is a value of 1. A value of “air replacement” of 0,6 or higher is sometimes used as a criterion in order to search for leaks. The air losses are calculated at a pressure of 50 Pa, the n50 value. Passive House Platform states, in imitation of their German colleagues, a degree of tightness n50 of 0,6 h-1.