Ever notice a breeze in older buildings even when it is not windy? Many buildings leak air, which means their owners are losing money. The Charlotte Mecklenburg School System (CMSS), the 19th largest in the U.S. with a $1.3 billion operating budget, recently decided to take action to identify school system buildings that might be exhibiting air leakage.
In early 2014, CMSS approved an architectural/engineering guideline change proposal to incorporate air barrier testing for all new buildings, additions, and major renovations. Using this guideline, CMSS’s plan was to decrease the air leakage from 0.25 cubic feet per minute (cfm) per square foot of exterior enclosure for buildings built in 2014 to 0.15 cfm per square foot of building enclosure for buildings built in and after 2018.