We have developed a system to achieve airtightness demanded by the passive house standard; by wrapping the building on the outside with a vapor-permeable airtight membrane (Sd<0,2). This makes all interior installations much easier. The membrane must be covered with an at least 60mm thick wood fibre board.

Exfiltration of warm, humid air to the exterior in winter can produce large amounts of harmful condensation in a construction. The airtight but vapor diffusion open membrane (sd<0,2m) lets vapor pass through easily, but blocks the problematic airflow. Not only do you reduce your energy bills, but you protect your construction from long-term damage.