Frequently Asked Questions (FAQs)

16.   Measuring Building Performance - how do we test for air tightness?

For either new or existing buildings a detailed and accurate measurement of air leakage is important to fully understand the energy performance of that building. Up to 20% of a building's heating and cooling can be lost by uncontrolled air leakage of the building envelope. New, highly energy efficient residential buildings should have a natural air leakage rate of no greater than 0.5 air changes per hour natural (achnat). Internationally, the accepted range for energy efficient housing is between 0.3 and 0.5 achnat.

By using a blower door device we can identify the overall leakage area of the building . Blower door technology is used in many countries, where energy efficiency is mandated, to measure the air tightnessof building envelopes, diagnose and demonstrate air leakage problems, estimate natural infiltration rates, estimate energy efficiency losses from building air leakage, and certify construction integrity. A Blower Door consists of a large fan which is mounted in a frame. The frame is placed in an exterior door and used to either depressurize or pressurize the house. From the resultant pressure readings, a calculation of the natural leakage of the house air changes per hour natural (achnat) is done.

Once the the problems have been identified these can be addressed and as a result maximize the energy performance of the building.

Download the Blower Door Test brochure