Air permeability testing is a central part of  SAP and SBEM calculations. The test determines how air tight a building is and contributes to the fabric calculation within SAP and SBEM. Most individual new buildings need an air test. Some dwellings can apply for an air test exemption but designers find the cost of upgrading heat loss elements needed to counteract the air test penalty prohibitively expensive.

O Ensure the company you use is accredited and uses calibrated equipment.

O Make sure your architect/SAP assessor has set a realistic air tightness target.

O Dot and dab plasterboard using the continuous ribbon method.

O Seal gaps between floors and walls before you put on skirting board.

O Caulk the top and bottom of all skirting.

O Seal gaps around the perimeter of all penetrations (electrical and plumbing).

O Penetrations, gaps between floors and/or pipework and plasterboard should be sealed before you box them in.

O Seal gaps between plasterboard and floors under kitchen units before the units are installed.

O Check that plasterboard and pipework behind bath panels have been properly sealed before the bath is installed.

O If installing spotlights use the correct core cutter and avoid poor quality or tilting spotlights.

O Eves cupboards, loft hatches and other openings to unconditioned spaces need to be as air tight as possible.