Experts explain acoustical issues for retail
and what to do about them
BY CAROL BRZOZOWSKI
How does this sound? Longer dwell time, better conversion rates, more engaging experiences, and better relations with neighboring tenants. These are the benefits retailers can derive from acoustical design strategies.
Felt ceiling slats modify the sound from hard surfaces within this Bergmeyer-designed restaurant in Pennsylvania. The ceiling and roof were restructured to accommodate the added weight. PHOTO: RICHARD CADAN PHOTOGRAPHY
Driving factors for acoustic focus
Acoustic performance in a retail space contributes to overall employee and customer comfort, whether it’s reducing background noise or improving sound transmission throughout the space, notes Stefanie Young, VP of technical solutions for the U.S. Green Building Council (USGBC).
And comfort can increase dwell time — and sales. “There’s a direct relationship to the amount of time someone spends in a retail environment and how much they spend,” says Nathaniel Fletcher, acoustical consultant for environmental consulting firm AKRF. “Numerous studies show that people are going to spend more time in an environment that they’re comfortable in. If we can create an acoustical environment that’s not overly noisy but not overly quiet, we can find an acoustical sweet spot [and] get shoppers to spend more time in those environments.”
With its relation to comfort and influence on sales, acoustic design is poised to attract more focus in retail, particularly among green-building and wellness-oriented projects. The WELL standard addresses acoustics in several ways in its Comfort concept. The relatively new standard is being applied to over 30 retail projects, according to the International WELL Building Institute. For the more established LEED standard — used for over 12,500 retail spaces worldwide, according to the latest LEED in Motion: Retail report — acoustic design is addressed in two credits.
One addresses the holistic consideration of background noise levels in a retail space, sound transfer between retail spaces, and how sound will reverberate within a given retail space. The other addresses the evaluation of the environmental noise from the retail building and/or the retail site and the corresponding impact on community noise, Young explains.
“We haven’t seen acoustics emerge as a priority for retail spaces pursuing LEED, but with the introduction of LEED v4.1, we expect more will consider it,” she says.
Left: At this DMD-designed Swissport lounge in Calgary’s airport, stretch-fabric panels, soft furnishings, and carpet dampen the background noise of the terminal to help travelers relax. PHOTO: DAVID WATT PHOTOGRAPHY Right: Designed by api(+), this Hannaford grocery in New Hampshire reduces noise levels in the in-store cafe with an acoustic wall. PHOTO: MARK A. STEELE PHOTOGRAPHY
Prevailing issues and strategies
The most common acoustical problem is hearing sound from one tenant to the next, especially if a wall is shared with a fitness center, says Gary Ehrlich, founder of Hush Acoustics, a Virginia-based acoustics consultancy. For spaces with the noise level of a fitness center, the spillover can be mitigated by using double-stud walls with multiple layers of drywall, fat insulation between the studs, and sealant in all gaps where conduits penetrate the wall and where the wall meets the floor slab, he advises. Thick rubber mats help address impact noise.
For retail space sounds and user experiences, Ehrlich recommends the use of soft room finishes to minimize reverberance. Appropriate finish types include acoustical tile, carpet, fabric-faced fiberglass wall panels or tectum ceiling panels that are designed for sound control.
Another issue is mechanical system noise. In addition to affecting the retail space itself, noisy HVAC systems can impact adjacent tenants, Ehrlich says. Sound attenuation strategies include mounting vibrating equipment such as an air-handling unit, using spring vibration isolation hangers, and addressing noise in ducts.
Fletcher points out that noise levels over 90 dBA, such as has been measured in some restaurants, not only makes conversations difficult, but puts people at risk for noise-induced hearing loss after one to two hours of exposure, according to the National Institute for Occupational Safety and Health.
He notes that today’s emphasis on the customer experience has acoustical implications. Designers need to consider the acoustical capacity of a space. “The larger a space is, the quieter it will be,” he says. To a lesser but still important extent, the less reverberant a space is, the quieter it will be, he adds.
Another factor is existing background noise level, a combination of the HVAC noise and background music. This can create a loud environment as people try to speak over background noise levels, Fletcher says.
A driving factor in footprint size needs is expected capacity, says Fletcher. Retailers and restaurateurs must find a balance that maximizes the number of people per square foot while ensuring that the environment is comfortable for patrons, he adds.
“What will typically work is maximizing the volume per person in the space and then making up any difference by introducing acoustically treated surfaces within the space,” he says.
A 20mm acoustic layer over an acoustic mass in this laminate flooring helps to maintain a quiet ambiance for this FITCH-designed meditation studio in Phoenix. PHOTO: RELENTLESS PHOTOGRAPHY
Growing product solutions
The past decade has brought an expansion of acoustical materials available. Designers are moving beyond traditional acoustic ceiling tile toward exposed concrete, exposed infrastructure like ductwork and plumbing, and hard surfaces like glass, brick, and concrete, says Fletcher.
“Fabric-wrapped panels work, but clients are asking more about microperforated wood with acoustical media infill. This is like an acoustical panel, but instead of fabric on it, it’s wood veneer with microperforations to allow sound to pass through the wood veneer and be absorbed by the media behind,” he says.
The acoustical products market is creating more acoustical options that meet the aesthetic design goals that architects and designers want to see, says Fletcher. Case in point: perforated drywall with acoustical media behind the skin finish to create a drywall look that offers the performance of an acoustical panel. By employing strategies to address the acoustics of a space, retail project teams can help create spaces that are more comfortable for occupants and more profitable for retailers.
The Gensler-designed b8ta store in Santa Monica, Calif., U.S., surrounds VR and sound-demo zones in a felt “hood” that acts as an acoustical device. PHOTO: RYAN GOBUTY
Carol Brzozowski is a freelance writer who frequently covers environmental, educational, and healthcare topics.