Greatest (new) thing in air sealing?
The importance of air sealing is emphasized at every point by GBA and other organizations that use building science for designing (!) and retrofitting residential housing. It is a cornerstone for energy efficiency and for controlling air quality, and also for comfort in buildings. Good air sealing is a prerequisite for using increased amounts of insulation that may reduce energy flow and drying potential in walls and ceilings.
Unfortunately, understanding air leakage and energy flow, ramifications thereof, and learning new building techniques and materials and code requirements (and how to interpret/translate these code requirements for code officials) seems to be foreign territory for a majority of builders and contractors and architects (and code officials), i.e., the professionals that Joe and Jane Public rely on to build and upgrade homes. What a state of affairs. (End of sidebar rant.)
With this as background, I found myself immensely interested in recent news stories about Aeroseal. I’ve been peripherally aware of Aeroseal as a duct sealing tool, but since my ducts have always been inside the building envelope, I’ve been less interested in duct sealing than some people that live farther south. But the concept is great: pressurize the ducts, and then inject an aerosol sealant that flows to leaks and starts sealing them. Air flow is monitored as leaks are sealed, and the process continues until (a desired leakage reduction is achieved). For duct work, 1-2 ounces of sealant is generally sufficient. [This is my summary version of the process.]
Recently I’ve read about the Aeroseal company testing the AeroBarrier aerosolized sealing system that “creates an air barrier around ceilings, walls, floors, doors, windows, and electrical and plumbing fixtures, spraying sealant particles that travel to openings and build up and bond together to seal holes. The firm says the technology can seal gaps up to ½-inch wide and as small as a human hair.” [BuilderOnline, Nov 2017]
And now, an article at JLC [Mar 2018], says that production builder Mandalay Homes has been using the AeroBarrier system “to reliably bring houses down to 0.3 ACH50, time after time.” The description of the process and the results that they’ve had on ~80 houses since July 2017 sounds relatively simple, compared with the heroic efforts most high performance builders use to achieve anything close in sealing performance. Basically, AeroSeal does the same thing as they do for ducts, but they use a blower door to pressurize the house to 100 Pa and then use 6-8 aerosol nozzles to spray sealant throughout the house. The air flow is monitored in real time during the sealing process.
To me, this is revolutionary, with the potential to greatly effect both new builds and perhaps more importantly, retrofits. If the REALIZE group is looking to “adapt the Energiesprong approach to the U.S. housing market” [GBA, 13Mar2018], this seems like a tool to consider.
What’s not to like? Is anyone other than Mandalay Homes testing this system yet? I know it’s early days, but I’m enthusiastic about the idea. What am I overlooking?
P.S. No, I’m not a company employee or shareholder.