Blower Door Testing

As per the International Energy Code of Construction 2012, “The building or dwelling unit shall be tested and verified as having an air leakage rate of not exceeding [...] 3 air changes per hour in Climate Zones 3 through 8."


Our Retrotec US-6102 Hi-Power Blower Door depressurizes your structure to negative 50 Pascals, relative to the outside. The DM32W Digital WiFi Gaug determines the air flow at that pressure and divides it by the volume of the dwelling to get the Air Changes per Hour at 50 Pa (ACH50). 


​While we are entirely in Zone 6: IECC's Climate Zone Map, Montana only requires dwellings to be held to a leakage rate of 4.0 ACH50 or less.


If the result is greater than 4.0, we can help locate leaks in your structure's envelope using thermal imagery, smoke tests, and visual inspection. Our work is backed by decades of experience in construction and building systems engineering.


Pre-mitigation goods and services are available. Inquire about the Blower Door Pass Package for new construction.