Air leakage can increase heating and cooling costs over 30% and contribute to comfort, health and safety problems. Finding hidden air leakage sites, called bypasses, can be difficult without the use of a blower door. This diagnostic equipment uses a fan to pressurize (force air into) or de-pressurize (force air out of) a building. When the fan operates, it is easy to feel the effects of infiltration – air leaking through cracks in the building envelope. Blower doors have gauges which can measure the relative leakiness of a building.
With the Blower Door tarp in place (red colored fabric) the house is depressurized by 50 pascals – a pascal is a unit of pressure. The equipment will then tell us how ”leaky” the building envelope is. We determined that the house was tight enough to gain the maximum allowable LEED points (3 each). Only 2 air changes per hour (ACH) occurred!
– Mike Lopez
