How do I improve the air pressure testing performance of my house or flat?

The air pressure testing performance of a house or flat can be improved cost effectively if care and attention is paid to particular areas of the dwelling. The most common areas in a dwelling that contribute to poor air tightness performance are junctions between materials and at significant penetrations to surfaces.

Some areas of a dwelling will be difficult to improve once a construction is complete as there may be little or no access, such as gaps between floor joists and the inner leaf of an external wall.

Many weaknesses in existing housing stock and new builds can be improved by attention to detail where services go into walls and floors, such as where water and waste pipes go though plasterboard below sinks or basins.

The diagram below is a cross section of a dwelling containing typical areas of weakness and possible solutions.