Air tightness and air leakages of new lightweight single-family detached houses in Estonia

A field measurement study of the air tightness and the air leakages of 32 detached houses was conducted during 2003–05 in Estonia. The buildings were classified according to the number of storeys, building technology, and the ventilation systems. Using the standardized BlowerDoor pressurization technique, the air leakage rate of each house was determined. To determine typical air leakage places and their distribution, an infrared image camera and a smoke detector were used. The mean air leakage rate at the pressure difference of 50 Pa in the entire database was 4.2 m3/(h m2). The mean air change rate at the pressure difference of 50 Pa from the entire database was 4.9 1/h. It was found that the number of storeys and the quality of workmanship and supervision play a significant role in the condition of air tightness. The typical air leakage places in the studied houses were: the junction of the ceiling/floor with the external wall, the junction of the separating walls with the external wall, penetrations of the electrical and plumbing installations through the air barrier systems, penetrations of the chimney and ventilation ducts through the air barrier systems, leakage around and through electrical sockets and switches, and leakage around and through windows and doors. According to the questionnaire conducted, fluctuating room temperature, cold floors and draught from electric sockets were related to the houses with air leakage rate >3 m3/(h m2) at 50 Pa.