CENTERVILLE, Ohio — Aeroseal duct sealant helped Ohio State University’s (OSU’s) William Hall Complex Extension project save considerable expense. When tests indicated that the new building’s ventilation shafts had unacceptable leakage, engineers faced the possibility of having to tear down many of the new walls and manually seal each of the leaks. The unexpected work would have had a significant impact on project costs and set the completion date back by half a year or more.

Fortunately, someone on the engineering team had heard about Aeroseal’s sealing technology. With this solution, workers were able to seal all 19 shafts of the six-story dormitory building in less than two weeks, saving costs and allowing the construction schedule to remain on track.

“After looking at the daunting possibility of redoing much of the finished construction work, finding out about Aeroseal was a huge relief,” said Ruth Miller, senior project manager, OSU. “The shafts were constructed of three layers of fire-rated drywall, so fire couldn’t get through, but the leaks meant that smoke could. To pass fire code and ensure the safety of building occupants, the leaks had to be sealed. Aeroseal did the trick.”

Originally developed at Lawrence Berkeley National Laboratory, the sealing technology, offered by Aeroseal LLC, seals leaks from the inside of duct systems and ventilation shafts, to more easily treat otherwise hard-to-access leaks. Applied to the interior as a non-toxic aerosol mist, in this application the mist was pumped throughout each ventilation shaft. The Aeroseal particles would stay suspended in air until they came across a leak. There the particles would accumulate around the hole and bond to each other until a permanent seal was formed around the leak.

“All of the vertical exhaust shafts throughout the building initially failed the pressure tests that measure leakage,” said Fred Bressett, product specialist for Aeroseal. “When we finished, nine days later, each shaft passed with flying colors. We didn’t have to tear into the walls and we were able to keep the project on schedule. Most importantly, the ventilation system is now working as it should, reducing the risks associated with fire hazards, and improving ventilation efficiencies.”

“Aside from decreasing fire safety, the leaks would have had a direct negative impact on the day-to-day ventilation of each of the building’s dormitory suites,” said Miller. “They would have also increased the building’s energy usage and operating costs, keeping the building from attaining its intended LEED Silver energy efficiency certification.”

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Publication date: 7/23/2012