By Ben Graham, Project Manager of Energy Ratings and Field Services – PCD Engineering
Air leakage testing, Blower door testing, infiltration testing, and airtightness testing are just a few names it goes by. No matter what you call it the names all mean the same thing. The tests measure the air leakage rate in the building. The 2009 International Code series was the first majorly adopted code to include it in code pathways and most subsequent residential energy codes and 3rd party energy efficiency programs include it in some form. Air leakage testing is also making its way into state and municipal commercial codes and is required on the United States General Services Administration and all United States Army Corps of Engineers projects. The testing metrics are slightly different, but the concept is the same: tighter is better.
A building’s infiltration rate is such an important data point in determining a building’s energy efficiency, comfort, durability, and environmental quality but it is a tricky piece of the puzzle to manage as a builder. The air leakage test is performed when the building is nearly 100% built using an orifice blower door, so if the building tests poorly it is very hard to correct. Additionally, it is hard to determine where the specific problem areas are located on the envelope. Sometimes the general construction methods fall short of design standards, and proper air barriers on assemblies were not incorporated, or air sealing and joint sealing in hard-to-reach areas were not installed. As the code requirements for infiltration advance, the design and construction world is working quickly to catch up.
PCD Engineering has many years of experience performing building air leakage testing on residential and commercial projects as part of our commissioning services, per standard ASTM E779, ASTM E1827, and ANSI/RESENT 380. We are seeing many code departments across Colorado incorporate this testing in new iterations of commercial codes.
We recently performed building air leakage testing on two notable projects using a blower door. One was the brand-new City Market building in Carbondale, Colorado. This large commercial space was one of the first in the Roaring Fork valley to be held to the strict 0.40 cfm/square foot envelope testing target. The building is a whopping 57,000 square feet and tested in at .274cfm/square foot, 32% below the target! PCD Engineering recently tested a 1600 square foot single-family home in Dacono, Colorado for Habitat for Humanity that came in at 0.72 ACH@50, 76% tighter than the 3 ACH target for the 2018 International Energy Conservation Code!
These two very different structures had one thing in common, they both utilized spray foam in the building envelope. I am not saying you need to spray foam your building to pass these tests. I think tight building envelopes can be achieved with good design and attention to detail. However, spray foam seems to be an effective tool to consider now while building envelope design catches up to the new codes.
Other notable airtightness testing clients include Colorado School of Mines, City of Boulder Scott Carpenter Pool Bathhouse, and Boulder County Jail Expansion. Future testing will be completed for the United States Army, University of Wyoming, and others. Visit our website for a full list of building envelope testing and advisory services, and contact us to help tighten up your buildings, make them safer, more comfortable, and reduce operating costs.