A numerical study on the role of leakage distribution and internal leakages under unsteady wind conditions

The existence of air leakages in a building has been very clearly stated as an important reason for energy loss. The decrease in the efficiency of the mechanical ventilation has also been clarified. The global demand for achieving nearly zero-energy buildings makes the uncontrolled leakage paths even more undesired. Despite the fact that steady state measurements of in- and exfiltration rates offer a simple and easy way of estimating the airtightness level of an eclosure, a supplement to those methods might be imposed.

Validating and improving the delta-Q duct leakage test

The Delta-Q duct leakage test has been developed over the past several years as an improvement to existing duct pressurization tests. It focuses on measuring the air leakage flows to outside at operating conditions that are required for energy loss calculations for duct systems, and infiltration impacts. The Delta-Q test builds on the standard envelope tightness measurement technique of a blower door by repeating the tests with the system air handler off and on. This study uses detailed

Evaluation of two new duct leakage measurement methods in 51 homes

Duct leakage in forced-air distribution systems has been recognized for years as a major source of energy losses in residential buildings. Unfortunately, the distribution of leakage across homes is far from uniform, and measuring duct leakage under normal operating conditions has proven to be difficult.