Aerosol Sealing

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. 

The WCEC has also investigated the use of aerosols for sealing underground natural gas pipelines. Proof-of-concept testing showed leaks could be sealed in a 1.6-inch diameter tube more than 125-feet from the point of injection, demonstrating feasibility of the process in gas piping infrastructure.

Current Work

The WCEC is currently contracted with the Center for Energy and Environment on a project for the DOE Building America Program that is assessing the aerosol sealing process in existing homes. Applying the process in existing homes requires significant preparation to avoid unwanted sealant deposition on finished surfaces. This project will develop protocols for preparing the homes for sealing and determine the effectiveness of the aerosol sealing process in existing homes. The current project focuses on applications during time of tenant change, when homes are temporarily unoccupied and contents are removed from the home.

Previous Work

The WCEC has worked on a number of projects related to aerosol sealing for the California Energy Commission, the Department of Energy Building America Program, and the Department of Defense ESTCP Program. Project reports and publications are referenced below and range from small scale laboratory testing to applying the process on a production scale with home developers.

Sponsors: Center for Energy and Environment, Department of Energy
Collaborators: AeroBarrier