Sto Corp. announced that its StoGuard fluid-applied air and moisture barrier showed significant air tightness during a recent blower door test on a project at Joint Base Lewis-McChord in Washington state.

In October 2009, the United States Army Corps of Engineers created requirements for building air tightness and building air leakage testing for new and renovation Army construction projects in or after Fiscal Year 2010. The testing, in accordance with ASTM E 2178, must demonstrate that the air leakage rate of the building envelope does not exceed 0.25 cfm/sq ft.

The project, which used the StoGuard system, passed with high marks. Where an acceptable score for the assembly would be 0.25 cfm/square feet, the assembly scored 0.18 cfm/square feet in initial testing, and 0.11 in final testing-a difference of 56 percent less air leakage.

The building tested, the Special Operations Forces Aviation Battalion Education Center, is part of the larger Joint Base Lewis-McChord Whole Barracks Renewal project. The barrier system, along with StoGuard Fabric, StoGuard Tape, and StoGuard Primer, was applied to this building and tested in late July.

At Joint Base Lewis-McChord, StoGuard “performed at a level that has not been accomplished since the USACE requirement for such testing began,” said Benham Hansen, the ACI-certified-project superintendent. “It is very uncommon after the initial test to accomplish more than a 0.02 or 0.03 difference for the final test. We were able to achieve a 0.07 decrease in cfm.”

Neudorfer Engineers Inc., which conducted the testing at Joint Base Lewis-McChord, confirmed to Hansen in correspondence that the Education Center is “the highest-performing building they have ever been associated with.”

“This was one of the first projects I’ve seen the StoGuard application go on, and it was one of the better tests I’ve seen,” said Phil Emory, senior project manager at Neudorfer. “0.11 cfm is extremely low and the results were because of the StoGuard product and application. This is a sensational building with an excellent product.”

A full copy of the test results can be found on the  Sto Corp. Web site.