Seal or No Seal

Back Article Apr 24, 2018 By Russell Nichols

Clean carpets, proper ventilation and special filters may help keep allergens out of the workplace. Another strategy entails sealing cracks in a building to make sure unwanted particles can’t sneak in.

Twenty years ago, Mark Modera founded AeroSeal, a company that uses aerosol particles to seal leaks in duct systems. Recently, as a professor and director of the Energy and Efficiency Institute at UC Davis, he developed a similar technology to seal building shells.

Related: As the Wind Blows

Related: Medical director of The Allergy Station on advancements in allergy treatment

In the past, Modera says, most builders did not methodically seal the shell of a structure. Now, new energy codes (California Title 24) require builders to tighten houses to a certain level. With the structure sealed, he says, building owners can prevent infiltration (uncontrolled outdoor air coming in) and also treat ventilation (controlled outdoor air) through HEPA carbon filters and other means.

Last year, AeroBarrier, an Ohio-based division of AeroSeal, began a project in Lodi to determine the best time to apply the aerosol sealing to reduce construction costs and improve tightness.

“Historically, that’s been a tedious manual process with caulk guns, trying to meet code by foaming or sealing anything they can see,” says Paul Springer, AeroBarrier’s manager of business development. “Our system takes the guesswork out of it.”

Controlled by a computer, the system uses a blow door, which measures the airtightness of a building. Sealant particles are pumped into the air and, with nowhere to hide, migrate to any cracks and coagulate due to the change in pressure or velocity, creating the seal. For the U.S. Department of Energy, this program is primarily to showcase the technology’s ability to seal leaks and, in turn, save energy. But along with proper ventilation, Springer notes, a byproduct of that would be better air.