Mobile app calculates sound transmission for wood-framed assemblies

The app is based on the “Technical Report 15 (TR 15), Calculation of Sound Transmission Parameters for Wood-Framed Assemblies.” That report addresses the 2018 International Building Code’s two parameters to establish minimum acoustical requirements: Sound Transmission Class (STC) and Impact Insulation Class (IIC).

Compliance with these requirements may be demonstrated through testing or through engineering analysis based on empirical test data from similar assemblies. The Acoustics App uses the AWC empirical model, based on empirical test data, to estimate STC and IIC values that can be used to demonstrate compliance of wood-frame floor-ceiling assemblies with these code-regulated sound transmission parameters.

“We released the TR 15 to simplify how wood-framed floor-ceiling assemblies can comply with the acoustical requirements,” said Brad Douglas, AWC vice president of engineering. “We’ve now taken it a step further by developing this free app. It is now even easier for code officials and designers to determine what wood-frame floor-ceiling assemblies can comply with code-specified acoustical requirements.”

New York City has two very large buildings dedicated to answering the 911 calls of its five boroughs. With more than 11 million emergency calls annually, it makes perfect sense. The second of these buildings, the Public Safety Answering Center II (PSAC II) is located on a nine-acre parcel of land in the Bronx. It’s an imposing 450,000 square-foot structure—a 240-foot-wide by 240-foot-tall cube. The gleaming aluminum cube risesthe equivalent of 24 stories from behind a grassy berm, projecting the unlikely impression that it might actually be floating. Like most visually striking structures, the building has drawn as much scorn as it has admiration.