IF YOU WANT TO really know what your home buyers are complaining about, or soon will, spend a night with your family in one of your newest two-story move-up homes ... ideally, one in that cluster you developed a stone's throw from the highway.

While you're there, settle in with a book in the cavernous, volume-enriched great room or get some work done in the den while one of the kids cranks up a DVD in the home theater upstairs and your spouse walks across the hardwood-finished hallway to throw a load of towels in the washer while a neighbor fires up a leaf blower outside in counterpoint to the constant din of passing traffic.

Noisy, huh? Admit it: You had no idea. Now imagine spending the next 30 years in that environment, paying off your mortgage. It's no wonder “noise” comes from the Latin word “nausea” and that, according to one study, more than 70 percent of new-home owners would be interested in noise-control products if their builder offered them.

There were warning signs, you know. “There's a convergence of factors driving greater demand for an amenity called quiet,” says Marc Porat, Ph.D., chairman and founder of Quiet Solutions, makers of new-age, sound-deadening drywall and subflooring, among a growing number of innovative sound-abatement solutions for residential construction. “We've got more environments that are more challenging,” he says, from the popularity of hard-surface flooring and cathedral ceilings to surround-sound home entertainment systems and dedicated home offices, not to mention infill development, zero lot lines, and even wind-resistant construction.

Multifamily and attached-home builders are at least riding the curve, if not necessarily ahead of it, thanks to stricter (albeit dubiously enforced and rarely field-achieved) code standards for higher sound transmission class (STC) ratings than those for detached dwellings. More so, perhaps, from mounting lawsuits and seven-figure settlements from condo and townhouse owners harried by ambient and impact noise traveling between units and from the outside environment.

Single-family detached builders, meanwhile, seem ambivalent at best ... so far. “Noise is not a life safety issue, so [single-family] builders don't typically pay a lot of attention to it,” says Nader El-Hajj, a project manager at the NAHB Research Center in Upper Marlboro, Md., which conducts third-party testing on a variety of materials, including noise-abatement products. “If people complain enough, builders will react.”

But how? Traditional methods—such as staggered or double-stud walls, resilient channels, and sound clips—add labor and materials costs, reduce valuable square footage, and/or have a high instance of field failure. While Porat and his peers refine material science to meet the need with newer and better solutions, El-Hajj and other experts implore builders to simply get smarter. “It doesn't take much to have a ‘soundproof' home,” says El-Hajj. “Materials and methods are available to builders who want to make it a priority. All they have to do is pay attention to details.” Here are some how-to tips and techniques to get you on board.

Home Offices

GOAL

Reduce sound transmission into the entire room.

BASICS
  • Specify engineered wood wall studs (some feature integral resilient channels on the inside edge) to create a sturdier structure.
  • Seal all electrical penetrations through the wall studs and both sides of the wall with expanding foam sealant.
  • Specify an acoustical mat, membrane, or subfloor system for the floor above, if applicable, to reduce impact noise from activity above.
  • Insulate ceiling with acoustical panels set in a dropped grid system or with drywall panels featuring integral metal and/or viscoelastic polymer layers.
  • Install carpeting, with a thick pad, as the finished floor material.
  • Specify a single, solid-core door held tight to its threshold and jambs to reduce sound transmission rather than using the gap under the door for passive air return.
    • SOUND RESOURCES

    Noise Pollution Clearinghouse www.nonoise.org

    National Council of Acoustical Consultants www.ncac.com

    Institute of Noise Control Engineering of the USA www.inceusa.org

    The Acoustical Society of America http://asa.aip.org

    Home Theaters

    GOALS

    Reduce sound transmission into and out of the entire room; contain high-decibel and low-frequency sounds.

    BASICS
  • Create a self-contained space, perhaps even with separate wall assemblies (ideally of ICFs, poured concrete or masonry, or SIPs) separated by a 1-inch or wider airspace from adjacent rooms; or, shared walls and floor/ceiling assemblies that are sound-insulated on both sides with an acoustical membrane or drywall/subfloor panels with integral metal and/or viscoelastic polymer layers.
  • Consider a separate and self-contained heating, cooling, and ventilating system that can not only be isolated and insulated against the noise it generates, but also set to an optimum climate for occupants and equipment.
  • Seal all electrical penetrations through the wall studs and both sides of the wall with expanding foam sealant.
  • Seal all light fixture housings in the ceiling.
  • Insulate floor, ceiling, and walls with full-depth fiberglass batts, expanding foam (underside of floor assembly only), and/or spray-applied cellulose insulation (walls only).
  • Install carpeting, with a thick pad, as the finished floor material.
  • Weatherstrip a single, solid-core and/or insulated door into the home theater.

    • LISTEN AND LEARN

    Despite what appears to be a growing consumer demand for sound-abatement solutions in housing, builders are understandably hesitant to offer “soundproof” homes for fear of not meeting a particular buyer's expectation of that term. “Noise control is not soundproofing,” says Portia Ash, residential noise control business manager for Owens Corning, which conducted a consumer survey on residential noise issues and concerns and offers an integrated system of insulation, sealants, engineered wall studs, and other components for sound abatement called QuietZone. “What's noise to you might be music to me.” To help builders accurately set buyer expectations about (and earn a return on) any noise-reduction methods and materials invested in the home's construction, Owens Corning is developing displays and other demonstration tools for sales presentations and model homes. “They will allow buyers to ‘listen' to different assemblies and noises through those assemblies,” says Harry Alter, a senior engineer with Owens Corning. “It'll give them an idea of what level of noise control they can expect.”

    First-Floor Platform Assemblies

    GOALS

    Reduce potential for squeaks; reduce ambient and impact noise from mechanical systems in/under the floor system.

    BASICS
  • Specify engineered wood I-joists at L/480 or higher span ratings (instead of code-minimum L/360) to reduce deflection (or bounce) that can cause furniture to rattle as you walk across the floor. Engineered wood I-joists, especially those with engineered wood chords, also are less prone to shrinkage than sawn joists, reducing the potential for fastener separation and squeaks.
  • Glue and screw-fasten a tongue-and-groove subfloor (plywood or OSB) according to the code and/or manufacturer-specified nailing pattern.
  • Use a nondrying/elastic acoustical sealant or caulk to seal all seams and joints.
  • Use gaskets or an expanding foam insulation/ sealant between pipes or electrical conduits installed within the webs of the I-joists (through provided cutouts or allowable holes) or vertically through the platform to keep them from touching or rubbing against the framing members or subfloor.
  • Hang or otherwise separate or gasket mechanical duct runs so they don't touch or rub against the framing members.
  • Install a vapor barrier at grade to reduce moisture vapor in the crawl space, which can cause shrinkage or warping (among other problems).
    • UPGRADES AND OPTIONS
  • Install an acoustical floor mat between two layers of subfloor or under a top layer of self-leveling gypsum concrete to reduce floor and flanking noise (see “Lingo Lesson,” right).
  • Install fiberglass batt insulation in the floor joist cavities to absorb a low level of noise and reduce thermal transfer and moisture condensation.
  • Install subfloor panels with integral metal and/ or viscoelastic polymer layers (a material that transforms sound energy into heat) to block flanking noise.
  • Insulate and seal ducts with fiberglass wrap and/or silver tape.
    • LINGO LESSON

    Flanking noise travels along a path of conductive framing members and components rather than directly (like ambient or impact noises); in fact, homes built with hurricane clips and other metal framing connectors that seek a continuous load path to withstand high winds and seismic activity are prone to increased flanking noise. “The correct way to build for extreme conditions is the absolute worst condition for noise,” says Marc Porat of Quiet Solutions.

    Wall Assemblies

    GOAL

    Reduce ambient and impact noise between rooms/ units and from the outside.

    BASICS
  • Properly install and seal all penetrations, including windows and doors, electrical outlets, and return-air vents.
  • Make sure the framing is dry (or has reached an equilibrium moisture content) before enclosing the envelope, to reduce shrinkage and warp that can cause fastener separation and fissures that allow sound transmission.
  • Insulate wall cavities with full-depth fiberglass batts or blown-in cellulose.
  • Seal all penetrations through the wall studs with a foam sealant or gasket to keep pipes and conduits from touching or rubbing on the framing members.
  • Apply an acoustical sealant to the wall–floor joint.
  • Weatherstrip all exterior doors; use solid-core and/or insulated doors.
    • UPGRADES AND OPTIONS
  • Specify multiple layers of insulating glass separated as much as possible, with one pane laminated for impact resistance (which also reduces sound transmission).
  • Install exterior sheathing panels and/or interior drywall panels with integral metal and/or vis-coelastic polymer layers to block sound transmission through the wall.
  • Install a flexible membrane behind the drywall to absorb sound transmission from the wall cavity and the outside.
  • Specify solid-core interior doors held tight to their thresholds and frames to reduce sound transmission between rooms rather than using the gap under the door for passive air return.
  • Use ICFs or SIPs instead of traditional wood-framed exterior walls to create a superior “mass load” to block sound transmission.
  • Specify structural engineered wall studs to further reduce shrinking and warping. Some engineered studs may also feature integral resilient channels that reduce the labor costs of installing the channels separately and field failures common with that noise-abatement solution.
    • FIELD FAILURE

    While wall assemblies built to achieve an STC rating of 40 or higher can meet that standard in the lab, thus validating the performance for code compliance, the chance of replicating similar performance in the field is less likely. “The problem is that as all the trades [come through] the house, they penetrate the barriers and let sound through,” says the NAHB Research Center's Nader El-Hajj. “Combined or individually, even small gaps let in sound.” In addition, standard windows, especially operable units, are notorious sound-leakers (doors aren't much better), unable to match the STC rating of the best-built walls, thus further degrading the performance of the assembly.

    Floor-Ceiling and Volume-Ceiling Assemblies

    GOALS

    Reduce ambient, flanking, and impact noise between two levels/units with a shared floor/ceiling; reduce reflective noise from inside rooms with volume ceilings.

    BASICS
  • Refer to “Basics” in “First-Floor Platform Assemblies,” page 390.
  • Specify insulated/sealed recessed light fixture housings and foam-seal around openings at the drywall for all ceiling-hung light fixtures.
  • Use flexible/woven joint tape at all drywall joints to bridge panels and reduce the potential for wall cracks.
  • Install an acoustical layer (foam mat, sheet membrane, subfloor panels with integral metal and/or viscoelastic polymer layers) on the floor side of the assembly to reduce impact noise transmission. Note: Foam mat is sandwiched between two layers of subflooring; sheet membrane is installed between floor frame members and a single subfloor panel.
    • UPGRADES AND OPTIONS
  • Insulate floor cavities with full-depth fiberglass batt insulation; cut and/or form around penetrations and light fixtures.
  • Install an acoustical layer (foam mat, sheet membrane, drywall panels with integral metal and/or viscoelastic polymer layers) on the ceiling side of the assembly to reduce impact noise transmission.
  • On flat ceilings, install acoustical panels in a dropped grid frame to absorb reflective sound and block impact sound from above.
  • On volume ceilings, install a fabric membrane over an acoustical panel to absorb reflective sound.
  • For the roof, consider SIPs, which usually permit longer/open spans on the interior, are self-insulated, and have substrates ready to finish upon installation.

    • CODES COMING?

    Sound transmission standards for all residential buildings are already in the building code as well as guidelines set and enforced by HUD, the EPA, and other agencies. But even heightened awareness (and litigation) regarding sound performance will not likely push more regulations on builders to reduce noise, especially for single-family detached homes. “Just raising the STC rating won't do it,” says the NAHB Research Center's Nader El-Hajj, noting not just the likelihood of field failures but also the inability to enforce higher standards beyond a plan check. Owens Corning's Portia Ash agrees: “It'll have to be consumer-driven, because most of [the noise] we're talking about is generated by the owner, so it's subjective.” But she does see the potential for stronger noise-related codes for homes near airports and highways. Even then, says Quiet Solution's Marc Porat, single-family builders herded onto such parcels by sprawl-deterring policies face a marketing nightmare: “Developments on the side of a highway are not sellable,” he says. “People walk in [to a house], hear the persistent rumble of the highway, and walk out.”