Pressure on air seals - Build 165(2018)
- Pressure on air seals
- Valid from
- Information provider
- BRANZ Limited
- Information type
- BUILD article
Air seals play an important part in stopping air carrying water into a building. Understand why they are used and how to install them, and you should get them right every time.
AIRFLOW THROUGH A WALL system will carry any water that might be present into the framing cavities and potentially inside the building.
A key function of drained and vented cavities is to ensure the air pressure behind the cladding is the same (or almost the same) as the pressure on the outside face of the cladding. This prevents air flowing across a wall system as the pressure inside the building is typically lower than that outside.