Measurement of building leakage by unsteady pressurisation

The paper describes the development of unsteady pulse pressurisation techniques for measuring the leakage of buildings. The original version of the technique (the UP technique) has been investigated experimentally and theoretically in a single cell test space. The initial results are very promising, with a good degree of repeatability and similar sensitivity to changes in leakage levels as the conventional steady (DC) technique. An interesting outcome of these early tests was the observation that quasi-steady flow could be established in a short time. This has led to a second version of the technique (the QP technique) and evidence is provided which indicates that this version could offer greater accuracy than the UP and DC techniques.