Airtightness testing is a key step in improving the efficiency of buildings of any age. This is due to the fact that air leakage through the building envelope can lead to a significant amount of energy loss.
Passivhaus Designer at Warm: Low Energy Building Practice Associate Lecturer University of Plymouth
One of the most useful (I’d say vital) things to do at the start of a retrofit project is an air test. Leak-finding while the building is depressurised gives so much useful information and should help to inform the strategy moving forwards. Although there have been studies which give typical results for different ages of house, that doesn’t actually tell you the magnitude or the location of leaks in your building. In a study of 6 homes, part of a large rural portfolio, we found that we simply couldn’t guess the airtest result from the age of house, its construction type, or the amount of work which had been done to it. In fact, the house which had received the most comprehensive renovation works previously was by far the leakiest. The leaks were always in similar places though, and this sketch shows where they were. Although it shows internal wall insulation on here, the leaks were in the same locations on pretty much every property, insulated or not, only varying in magnitude. These were all found by using the back of the hand, listening for air movement or noting a colder than average area and exploring that location further. I’m always very keen to attend air tests and really enjoy trying to work out the leak paths, maybe that means I should get out more!
