Apartment buildings

The air tightness of eight apartment buildings containing six to eleven units each on three or four floors has been tested with and without guard-zone pressure, i.e. with and without consideration of internal leakages. The layouts of these buildings varied: two of them had no central stairwell, in two other buildings, only some of the apartments were connected to the central stairwell, and the third type had all apartments connected to a central stairwell.   During these tests, two to eight BlowerDoor systems were used simultaneously to create guard-zone pressure conditions.