Sound solutions to a noisy
problem
| The science of building or architectural acoustics is a well-developed
field, yet rarely called into application in construction of residential
houses and apartments, writes T. NANDAKUMAR. |
Moving from an independent house in a quiet neighbourhood to
a fourth-floor luxury apartment at one of the prime locations in the city has
proved to be traumatic for Sreehari and his family of five.
The incessant stream of traffic on the road is a relentless
assault on their acoustic faculties, depriving them of peace of mind. So much
so, that the family is now thinking of selling off the apartment and shifting to
the suburbs.
Stress
factor
Studies on acoustics have proved that there are optimum sound
levels for sleep, relaxation, speech, communication and stage performances.
Excess sound forms a stress factor and can be a cause for several health
problems including hypertension, mental trauma and irritable behaviour.
The science of building or architectural acoustics is a
well-developed field, yet rarely called into application in construction of
residential houses and apartments.
Examples of aesthetically appealing buildings with poor
acoustics abound in the urban milieu, auditoria where not a single word or
musical is audible or intelligible, offices too noisy to work in, factories with
high sound exposure levels and even houses exposed to high levels of noise from
traffic and other sources.
Prolonged exposure to noisy environment in homes and places
of work could lead to loss of hearing. Studies indicate that workers in noisy
environment suffer from circulatory, digestive, metabolic, neurological, cardiac
and psychiatric symptoms. High-decibel sound affects efficiency in performance
and causes behavioural changes.
Abstruse
effects
One of the abstruse effects of sound on man's mental and
physical health is sleep interference and disruption. Even if the sound does not
arouse a sleeping person, it affects sleep quality through subtle changes in the
sleep pattern.
Experts point out that sonic aspects are to be given focus
along with other considerations for human comfort in a built environment. Noise
barriers can be scientifically created to achieve acoustic comfort. Planting
creepers and shrubs in the space between the building and the road helps to
filter out noise, but only to some extent. "In a typical urban setting
characterised by high noise levels, the ultimate solution is to apply
architectural acoustics in the construction of a building," says Shaji T.L,
faculty member, Department of Architecture, College of Engineering,
Thiruvananthapuram.
"One of the means of controlling exposure of noise in a
building facing a busy road is to minimise the number of openings towards the
source of noise. But this involves a great deal of planning to ensure that it
does not mar the aesthetics or affect the circulation of air inside the
building. Doors and windows will have to be carefully positioned to cut out the
noise, yet ensure adequate ventilation," explains Mr. Shaji.
Glass
surface
One suggested method is to provide a fixed double glazed
glass surface on the road-facing side of the house or apartment. But unlike
hotels or commercial establishments, houses do not generally have centralised
air conditioning. The loss of ventilation can be compensated by providing large
windows on the other sides.
Another method is to position a road-facing window in such a
manner that it opens into a blank wall that serves as a reflecting surface. Even
correct positioning of the gate can cut down noise levels significantly.
Noise
insulator
Brick is considered a good noise insulator. Constructing
brick walls with a continuous hollow between the layers is an effective method
of insulating a building from external noise sources. "Since the columns
bear the load of the building, constructing hollow brick walls does not affect
structural stability," says Mr.Shaji.
Another cost- effective means of cutting noise intrusion is
to raise the height of the compound wall and position flowerpots and shrubs on
top of the structure as a natural filter.
Experts advocate detailed planning in the design stage to
ensure acoustic comfort.
Courtesy: Property
Plus, The Hindu
http://www.hindu.com/pp/2007/02/03/stories/2007020300650100.htm
