The Acoustics of Bathrooms
A PRIMER ON BASIC THEORY AND THE LATEST TECHNOLOGIES
In acoustics, when we joke about the worst-sounding spaces, we always refer to tiled bathrooms. Everyone knows
how bathrooms sound: echoic, reverberant and loud. As children in the tub, we all
loved to sing, clap and make funny noises
to play with the cool, cave-like sound of
being in the bathroom. As adults, bathrooms are often more than just a place for
basic human function. They are a place of
privacy, or even a spa-like place of serenity. Like any such space, we prefer the
peace of a quiet acoustic environment.
Bathrooms are, by nature, wet and
humid spaces, designed to lock in heat
and moisture. The nature of this environment is the antithesis of a good-sounding
acoustic space. They require waterproof,
washable surfaces, which are traditionally
smooth and hard, while acoustic control is
traditionally soft, porous, rough and difficult to clean. This is why most bathrooms
are echoic, loud and highly reverberant.
Herein lies the challenge of creating
peaceful, quiet and serene bathroom environments. The good news is there are at
least two ways to make a bathroom sound
good – or at least much better.
1. Divide and Conquer
Split the space into wet and dry areas
applying traditional materials. The wet
areas should use traditional hard, water-
proof materials that are functional with
many options. These areas would include
the shower, tub and sink counter. The
dry areas are better off using traditional,
This mixed approach will help ease
the loud echoes and reverb of the hard
surfaces while letting the wet areas be
carefree, washable and waterproof like
every other bathroom. Like any surface,
over time the acoustic panels will need
cleaning and eventually replacement
of the textile covering. Wood slat floor
mats in conjunction with the long-haired
shag carpets provide a slight addition of
acoustic control. They also provide water
control and an anti-slip feature while
being comfortable to the touch.
2. Integrate New
Integrate new acoustic materials into
the wet areas to control at least high-fre-
quency flutter echoes. New sheer drapery
textiles are available from several large
textile firms that, according to testing,
have a noise reduction rating as high as
0.7. This means at mostly high frequen-
cies, the drapery will absorb roughly 70
percent of sound energy. Draperies made
from these textiles can act as a second
shower curtain on the outside to control
sound, while the inner curtain can keep
the water from soaking the acoustic drape
and keep the water inside the shower.
All other areas, such as the ceiling and
walls around the vanities and tub, can use
new bathroom quantum products made
with natural organic materials and water-
proof plastics to control all frequencies of
sound, including low and mid-low frequen-
cies. These devices are thin with many aes-
thetic options. They are manufactured with
mold-resistant and waterproof materials
and are easily disassembled for cleaning.
Of course, with all things, there are
compromises. The more acoustics you
apply in any wet area means the more
cleaning they will require over time.
However, this is true of all bathroom
materials, from sinks and towels to bath-mats. New, higher-performance technology also has a higher price tag than the
traditional, lower-performance materials.
The Silver Bullets
The good news is bathrooms are ubiquitous. That means there are always new
products introduced into the market, and
they often have the benefit of being dual
purpose: bathroom-friendly and good for
acoustic control. Additionally, new technology and products are always developed.
The large textile firms and quantum acoustic device designers continue to evolve
new products to control all frequencies of
sound while being water-resistant, mold-resistant and easily cleanable.
Acoustics is incredibly fun and fascinating. As the science underlying all of
sound, it brings us music, language and
an incredibly diverse world of intriguing sounds. It teaches us to care for our
health while improving our quality of life
in a variety of creative and artistic ways.
Hanson Hsu is the principal acoustician and founder of Delta H Design Inc.
(DHDI), a research, design, and build firm
providing design and consulting services
for architecture and acoustics since 1998.
CREATE A SERENE HOSPITALITY
ENVIRONMENT with good acoustics
instead of duplicating the typical
echoic, cave-like restrooms.