In explaining how noise-reduction products work to keep homes quieter, representatives from Owens Corning and Quiet Solution both refer to a wall's STC or sound transmission class.

"Typical walls have an STC in the low 30s or high 20s," says Portia Ash of Owens Corning, adding "the higher the STC, the better the wall." The STC itself is a measure of the number of decibels by which airborne sound is reduced as it passes through material. In addition to walls, the rating also can apply to doors and windows, noise barriers, and other acoustical products.

Quiet Solution's Kevin Surace says that soundproofing a room used to require adding mass to the walls, noting that doubling the mass of a wall increases the insulation by 5 decibels (dB). For example, by adding a second layer of gypsum to a regular wall, a remodeler can raise an STC 30 wall to STC 35. Initially, this seems effective. However, Surace says, mass can be expensive to create, ship, and install. Moreover, the amount of material needed to continue doubling wall mass increases exponentially with little additional impact. The example wall, for instance, would require two more layers of gypsum on each side to be doubled again, but still gains only another 5dB of insulation.

For a more effective and more economical route, Surace and Ash suggest looking for noise-reduction products that boost STC numbers without adding a disproportionate amount of material.

According to Ash, 78% of home buyers will report that they have problems with noise in their homes and 71% are interested in building noise control into their projects if it's offered. "When homeowners find out that there's a volume control for their home, so to speak, a light bulb goes on and they understand that incorporating noise control products into their homes will help them achieve the lifestyle they want," she says. So, instead of watching your clients change their behaviors to accommodate distracting house noise, consider offering noise-control products as a lucrative upsell opportunity. L.H.