Air leaks in buildings waste energy and can cause moisture and indoor air quality problems. Current methods for tightening building shells have relied primarily on manual sealing methods that are labor intensive and often insufficient. 

Since its inception, the WCEC has been developing applications for aerosol envelope sealing to improve sealing effectiveness, reduce labor costs, and improve contractor installation consistency. Former WCEC director, Mark Modera, developed a process for sealing ductwork remotely using aerosol particles while at Lawrence Berkeley National Lab in the 1990s and started a company, Aeroseal. 

In 2010, WCEC started to adapt the aerosol sealing process for sealing building envelopes. The process involves pressurizing a building while applying an aerosol “fog” to the interior. As the air escapes through leaks in the shell of the building, the aerosolized sealant is transported to the leaks and seals them as the particles try to escape from the building. The process has proven to be very effective at sealing leaks in building envelopes, consistently showing the ability to seal 80% of available leaks in less than two hours. The process for aerosol sealing of building envelopes was licensed to Aeroseal in 2016,which now provides the service under the name AeroBarrier through a number of dealers across the country.