Since 2006, Part L of the Building Regulations – The Conservation of Fuel and Power in England and Wales – has required mandatory air leakage testing of new buildings including homes. These regulations were further revised in 2010. But this does not mean every new home will be subject to an air leakage test to comply even under the latest 2010 Part L.
What is air leakage testing?
Air leakage testing basically checks that a new home is air tight and will not let in draughts or provide a route for heat to escape through gaps in the structure. After sealing up all required vents to windows and extractors, air is then drawn out of the home via a large fan in an external doorway, with the pressure monitored for a set period of time to produce a measurement of the amount of air that leaks back into the home being tested.