The airtightness of outside windows and doors is an important criterion for achieving an airtight building envelope. The Window and Door Measurement System developed by BlowerDoor GmbH allows you to determine the joint permeability of building components in a simple and accurate way. On the basis of the measurement results windows and doors can be classified in accordance with EN 12207 (windows and doors, air permeability-classification).
A foil with an orifice plate is fixed to the window to be analysed. With the Minneapolis BlowerDoor installed in a room or apartment, a pressure difference is created in the hollow space between the window or door and the foil. The foil slowly bulges inward. As soon as the hollow space is filled with air, the measurement can be started. The airflow entering through the window joints is measured by means of an orifice plate with a defined diameter, and the pressure difference on both sides of it (ΔΡ orifice). In order to evaluate the permeability of the joints, the corresponding pressure difference on both sides of the window is also measured (ΔΡ window/door). The results of the measurement can then be compared to the classifications of the EN 12207.