Statistics, analysis and conclusions from 250,000 blower door tests, including ventilation types

With lower air leakage in modern homes, ventilation of homes has become more important than ever before. It seems however that we are getting it very wrong. A lack of ventilation can cause building sickness, with degradation of the physical building and also poor air quality which has a big impact on the occupants themselves. Our statistics show that designers and contractors are still not getting it right, leaving us with a generation of poorly ventilated housing stock.