Clean air, natural light, thermal comfort, a productive ambience are all
elements of indoor environmental quality that come to mind when we think of
successful corporate interiors. They all contribute to occupant health and
performance. Paradoxically, however, sustainable design often leaves acoustics
out of the picture. Except in the case of LEED for Schools (with LEED Healthcare
on the horizon), there are no LEED credits for acoustics. This oversight is
compounded by the fact that designers can inadvertently compromise acoustics
when designing green.
It is not that acoustics are deemed unimportant.
Routinely, distracting noise and lack of acoustical privacy are at the top of
workplace complaints. In green buildings, it turns out, it can be even worse. In
a 2006 report by the Center for the Built Environment (CBE) at UC Berkeley,
surveys showed that occupants of LEED-rated and/or green buildings were found to
be more satisfied with their indoor environment than their counterparts in
non-green buildings. Yet, when it came to acoustics specifically, occupant
satisfaction was lower in green than in non-green buildings. (Click
here to view CBE chart.)
Designers are eager to
design sustainably, and sometimes their strategies—such as using fewer
materials, avoiding synthetics, limiting toxic materials and finishes, as well
as maximizing natural light—translate into open plan spaces with fewer walls,
high and exposed ceilings, and hard surfaces all around. These design approaches
can reduce the opportunity for sound absorption, creating inherently noisy
spaces. Leigh Stringer of HOK and author of The Green Workplace says, "More
often than any of us would like, green strategies present a challenge to
acoustics." For Stringer, this is no small matter. In fact, she categorizes
unwanted noise in the green workplace as a "productivity inhibitor."
Rectifying acoustical problems after a space is occupied can require
more complicated or costly solutions than if those issues were avoided in the
first place. So how can designers create sustainable spaces that also support
occupants' acoustical needs? Scot Horst, senior vice president of LEED at the
USGBC, feels that good sustainable design always requires an integrative design
process. "Green design presents challenges to acoustics, but hopefully it
encourages people to think more holistically about their projects so that they
pull in an acoustic consultant early on," he says.
Designers also can
focus on the specific spaces that require good acoustics. Today, the office
environment typically needs to support a variety of activities, from teamwork to
private concentration. Therefore, acoustical quality should vary according to a
space's function.
The good news is that manufacturers continue to
improve the green features of acoustical products such as ceiling tiles and
resilient floor underlays. The roster of quality sustainable products in general
also continues to expand, making the use of sound-absorbing materials not
necessarily marketed as "acoustical products" (such as carpeting), much more
attractive for the green designer. Current options for sustainable acoustical
products include cotton duct lining, cork, slotted wood systems, recycled cotton
wall panel cores, and cotton absorptive panels that can be used in place of
fiberglass. However, these materials come at a premium cost.
Making LEED
credits for acoustics available beyond LEED for Schools would stimulate
development of more affordable products as well as help raise awareness among
designers about its critical role in the indoor environment. Horst feels
acoustics is a strong candidate for the USGBC's recently launched Pilot Credit
Library program. This enables designers to recommend and provide feedback on
credits (as innovation points) and facilitates their eventual official credit
status in the broader LEED system.
David Lehrer, director of
communications at the CBE, feels there is a lack of awareness of acoustics in
the industry that LEED credits would help address. He compares acoustics' low
profile to another USGBC oversight. "Until recently, energy was somewhat
overlooked in LEED," says Lehrer. "You could have a very highly ranked LEED
building that merely complied with the energy code."
One reason the
USGBC does offer acoustics as a credit for LEED for Schools is that research
demonstrates the correlation between sound quality and learning in the
classroom. More research is needed to validate the impact of noise on occupant
health, comfort, and performance in the workplace.
Acoustics credits for
LEED, greater awareness, research, and more product options will help designers
create green spaces offering quality acoustics. Until then, designers should
know that it doesn't have to be a trade-off.
Victoria Cerami is the
CEO of Cerami & Associates, Inc., a globalacoustical, audiovisual, and
technology consulting firm.