Blower Door Testing

Recent editions of the International Residential Code that are referenced and adopted by local jurisdictions, now require blower door testing as outlined below:

“The building or dwelling unit shall be tested for air leakage. The maximum air leakage rate for any building or dwelling unit under any compliance path shall not exceed 5.0 air changes per hour or 0.28 cubic feet per minute (CFM) per square foot of dwelling unit enclosure area. Testing shall be conducted in accordance with ANSI/RESNET/ICC 380, ASTM E779 or ASTM E1827 and reported at a pressure of 50 Pascals.”

What is Blower Door Testing?

Now that air leakage, or blower door, testing is mandated per the residential code, what exactly is it? In order for air to flow, a pressure differential is necessary to move air from a higher, or positive, air pressure to a lower, or negative, air pressure. Therefore, this test produces both pressurization and depressurization using a fan, or blower, that is sealed within a building enclosure penetration, such as a door or window. Once the requisite pressure with regards to the exterior is maintained across the building enclosure, an air flow meter is used to calculate the amount of air flow, or leakage, through the building enclosure. The air leakage rate across a building enclosure is critical to performance, as higher air leakage rates can result in interstitial condensation and microbial growth, drafts that affect thermal comfort, significant increases in energy costs, and can tax the HVAC equipment of the home due to increased demand.

Why Blower Door Testing?

Beyond residential code requirements, verifying the air tightness of the enclosure also helps to:

  • Reduce Condensation Issues
  • Increase Thermal Comfort
  • Improve Indoor Air Quality
  • Reduce Energy Use and Cost (see graph below)
This graph shows the energy use based on insulation R-Value (black curve) and air leakage (orange line). More air leakage equals more energy use; whereas, more insulation starts to have diminishing reduction in energy use.

FCG’s Approach to Blower Door Testing

FCG is equipped with the state of the art Minneapolis Blower Door Model 3 System and DG-1000 Pressure Gauge and Flow Meter that efficiently and accurately measures the air leakage rate in accordance with ANSI/RESNET/ICC 380, ASTM E779 and ASTM E1827. With this blower door technology, FCG can provide test results to you or the building official the same day! In addition to measuring the air leakage rate, FCG is equipped with smoke generators and infrared thermography to help diagnose air leakage locations for repair should the enclosure not meet code requirements.

Contact us about availability and pricing for testing!

Finley Consulting Group, Est. 2021