1. Building acoustics involves controlling noise transmission between spaces and noise levels within spaces. Noise can reduce comfort and efficiency if it is troublesome.
2. The best way to address noise problems is to take proper acoustic precautions in the design and construction of a building. This ensures each space has the correct acoustic climate and noise transmission levels are compatible with usage.
3. Sources of indoor noise include activities like cooking, footsteps, doors slamming, furniture moving, plumbing, and appliances. Outdoor noise sources are traffic, construction, and landscaping activities.
1. ITM School ofArchitecture & Town Planning
Bakshi ka Talab, Mampur Bana , Lucknow
PRINCIPLES OF BUILDINGACOUSTICS IN
RESIDENCE
Lecture- 07
Subject
Code
Session
Year
:- Acoustics
:- AR -805
:- 2014-15
:- 4th Year (8th SEM) 1
Studio Directors:-
Asst. Prof. - Ar. Shalini Diwaker
B.Arch, VIII sem. ITM SA
TP
, Lko
AR-805/ 2014-15
2. Principles of building acoustics
Building acoustics is the science of controlling noise in
buildings, including the minimization of noise transmission
from one space to another and the control of noise levels
and characteristics within a space.
Noise can be defined as sound that is undesirable, but this can be subjective and depends
on the reactions of the individual. When a noise is troublesome, it can reduce comfort and
efficiency. If a person is subjected to noise for long periods, it can result in physical
discomfort or mental distress. In the domestic situation, a noisy neighbor can be one of
the main problems experienced in attached housing.
Solution
The best defense against noise is to ensure that proper precautions are taken at the
design stage and during construction of the building. The correct acoustic climate must
be provided in each space and noise transmission levels should be compatible with
usage. After the fact, when the noise problems are discovered, solutions can be very
difficult and expensive to resolve and in most cases there is no easy solution.
Noise
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Lecture
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07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
3. Sources of noise
Indoor noise:-_
As far as indoor noises are concerned, they
are:-
Kitchen disturbance.
Footsteps.
Banging the door.
Shifting the furniture.
Operating the cistern and water closet.
Playing of television , radio and music
system.
Cooling and ventilation machinery.
3
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Lecture
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07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
4. Noise conditions vary from time to time and
are clearly detected in night when there is
proper silence.
In case of flats the main source of noise is
noise from other flats , staircases and access
balconies.
In semi detached buildings the main noise
comes more from the outdoor streets.
4
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Lecture
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07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
5. The main sources of outdoor noise
in residential areas are traffic
(aeroplane , roadways , railways) ,
children playing hawkers , service
deliveries , road repairs , blaring
loud speakers , and various types of
moving machinery in the
building
neighbourhood and
operations.
Outdoor noise regulations:-
1.
2.
3.
For air traffic
Flyover noise
Ground noise
For rail traffic
For road traffic
Outdoor sources
5
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
6. 1. Sound focii
2. Dead spots
3. Sound shadow
4. Resonance
5. Insufficient loudness
6. External noise.
7. Reverberation.
8. Floor ceiling noise transmission
9. Footfall noise.
Defects in acoustics
6
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
7. OUTDOOR NOISE
INDOOR NOISE
MULTIPLE NO. OF REFLECTIONS OF SOUND
Conditions for good acoustics
in residential building :-
No or low background noise
1. Outdoor noise
2. Indoor noise
desirable/wanted sound should be
high
defects of sounds should be avoided
1. Dead spots
2. Soundless zones
3. Sound shadows
4. Resonance etc.
room acoustics and sound isolation
techniques should be properly
installed in the interior spaces.
less no. of reflected sounds
less reverberation time
7
•
Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
8. Design consideration
The acoustical design for a residential
out on two basic
building is worked
principles:
ROOM ACOUSTICS
SOUND ISOLATION
Room acoustics has the goals of noise
reduction and reduced
reverberations(echoes) for good hearing
conditions within a space.
Sound isolation is the control of the sound
transmission between the adjacent
spaces.
ROOM ACOUSTICS TREATMENT
SOUND ISOLATION TREATMENT
SOUND ISOLATION
AIR-BORNE STRUCTURE-BORNE
8
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
9. The term ‘building acoustics’ embraces
sound insulation and sound absorption.
These two functions are distinct and should
not be confused. Sound insulation
requirements of the building should take
into account both internal and external
sound transmission.
Sound insulation
Sound insulation is the term describing the
reduction of sound that passes between
two spaces separated by a dividing
element. In transmitting between two
spaces, the sound energy may pass through
the dividing element (direct transmission)
and through the surrounding structure
(indirect or flanking transmission). In
designing for sound insulation, it is
important to consider both methods of
transmission. The walls or floors, which
flank the dividing element, constitute the
main paths for flanking transmission, but
this can also occur at windows, heating or
ventilation ducts, doorways, etc.
9
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
10. Indirect paths (flanking transmission)
Flanking sound is defined as sound from a source room that is
not transmitted via the separating building element. It is
transmitted indirectly via paths such as windows, external walls
and internal corridors.
Flanking Paths Noise Leaks
F1 Open plenums - over
walls and through
suspended ceilings
L1 Poor seal at wall/ceiling
connection
F2 Common ductwork L2
Poor seal at wall/wall
connection
F3
Adjacent exterior
windows
L3
Poor seal at wall/mullion
connection
F4 Common floor heaters L4 Poor seal around outlet
penetration (also avoid back-to-
back outlets)
F5 Open vents L5 Poor seal at wall penetration
F6 Louvered doors L6 Poor seal at floor penetration
F7 Under doors L7
Poor seal at wall/floor
connection
L8 Poor seal around door
Sound absorption
Sound absorption is the term given to the loss of sound energy
on interaction with a surface. Sound absorbent surfaces are
used to provide the correct acoustic environment within a room
or space.
TRANSMISISON OF AIRBORNE NOISE
10
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
11. WALL TREATMENT
Noise reduction between two adjoining spaces may be caused by
the effect of the barrier or partitions.Therefore walls and
partitions which utilize mass, resilient mountings, sound
absorbing core materials and a combination of these principals
is used. for e.g. DOUBLE LEAF WALL.
FLOOR/CEILING TREATMENT
Floor/ceiling systems are a major sound barrier between living
units in a multifamily dwelling. It must block airborne sound and
also reduce impact sounds.
WINDOW/DOOR TREATMENT
Door and window treatment is yet another important issue
which should be taken care of while doing the acoustical
designing for a residential building. As they can help in reducing
the following:
• neighborhood noise
• Road traffic noise
11
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
12. ROOM ACOUSTICS :-
Room acoustics basically deals with the reduction in
reverberation time and impact sounds. It can be done with
the following methods:
USE OF SOUND ABSORPTIVE MATERIALS
Sound absorptive materials are used in a room where the
sound originates and thus reduce the sound transmission to
the adjacent rooms by lowering the sound level in the source
room. Sound absorptive materials lower the background
noise and thus help in listening to the actual wanted sound.
It also helps in reducing the reverberation time in a space
REDUCTION IN REVERBERATION TIME
Room volume is a significant factor in establishing the
reverberation time. In a typical residence size room,
reverberation time will be rarely longer than 3 to 5 seconds
even with no sound absorption. To make a living room
acceptable for speech, a reverberation time of 1 to 2 seconds
is recommended.
12
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
13. There are three criteria's in which following recommendations are given :
1. At Site Planning level.
2. At Internal Planning level.
3. Sound insulation in and outside.
Site
Recommended
Site
Not Recommended
NBC Recommendations :-
• Locate the residential building is minimum noise
zone ( away from heavy traffic area, industrial area,
etc.) of site.
• To minimize ground reflection, the dwellings should
be surrounded by the maximum amount of planting
and grassed area and the minimum amount of hard
surfacing.
• Avoid paved courts between adjacent buildings.
Recommended
Not Recommended
1. At Site Planning Level…..
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
14. 4. To minimized internal noise
provide minimum internal
road network.
5. Avoid play areas near the
residential area.
Not Recommended Recommended
2. At Internal Planning Level…..
1. The non-critical areas such as corridors, kitchens,
bathrooms, elevators and service space may be
located on the noisy side.
2. Critical areas, such as bedrooms and living space,
on the quiet side.
Windows and doors :-
Windows and doors should be kept away
from noisy side of the building.
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
15. Layout plans :-
1. Rooms adjoining party walls and above/below party
floors should be of similar use. Bedrooms are not
exposed to noise from adjoining living rooms, and
there is less risk of disturbance of sleep.
2. Rooms adjoining party walls and above/below party
floors should be of similar use. Bedrooms are not
exposed to noise from adjoining living rooms, and
there is less risk of disturbance of sleep.
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Lecture
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07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
16. External Noise Deduction Techniques
2. At Internal Planning Level…..
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Lecture
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07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
17. 3. Sound Control…..
OPTIMUM DESIGN OF PANELS
The control of sound in a building must be
considered from two aspects.
The elimination or reduction of unwanted sound
generated by source within or outside a building.
The creation of good listening condition with in a
building where clarity of speech and music is
required which must not be marred by sound
reverberation and echoes .
2 Layers
5/8” Gypsum
Board
Insulation
SoundPath
Unsealed
2 Layers
5/8” Gypsum
Board
Insulation
SoundPath
2 Layers
5/8” Gypsum
Board
Insulation
Sealed
Acoustical
Sealant
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Lecture
-
07
AR-805/ 2014-15 B.Arch, VIII sem. ITM SA
TP
, Lko
