BUILDING MATERIALS USED FOR SOUND INSULATION

1. SOUND
INSULATION
-PALLAVI PATIL

2. ACOUSTICAL TERMS :
 SOUND – A vibration or wave motion that can be heard ,
reaches the ear through air , the air vibrates back and forth in
tiny molecular motions of high and low pressure .
 DECIBEL – The unit of measurement used to indicate the
loudness or intensity of sound .
 REVERBERATION SOUNDS – Airborne sounds which continue
after the actual source has ceased , caused by reflections from
floors walls and ceilings .
 SOUND TRANSMISSION LOSS – The number of decibels which
loses when transmitted through wall or floor .

3. WHAT IS SOUND INSULATION ?
 “SOUND INSULATION’’ is the ability of building
elements or structures to reduce sound transmission .
 To compare sound insulation properties we need to
take into account the area of the dividing partition /
wall , as well as the volume and sound absorption
properties of the receiving room .
 To do this , measurements are normalized to a
reference absorption value or standardized
reverberation time .

4. SOUND INSULATION VS. SOUND
ABSORPTION -
The function of sound
insulation is prevention of
transmission of sound . It
is used to indicate the
reduction obtained when
sound passes from one
room to another room .
The function of sound
absorption is the prevention of
reflection of sound waves .the
process by which a material or
object takes in sound energy
when sound waves are
encountered as opposed to
reflecting the energy .

5. TRANSMISSION OF NOISE :
1. THROUGH AIR – This type of noise transmission ,
being common is important .
2. BY THE VIBRATION OF STRUCTURAL MEMBERS –
this type becomes prominent only when the enclosing
walls , floors , ceilings etc., are of thin construction .
3. THROUGH THE STRUCTURAL MEMBERS – This type
is prevalent where mechanical vibrations are caused ,
particularly in case of factories , work shops , public
buildings , offices etc.

6. TYPES OF NOISE :-
 Noise is defined as unwanted sound . Noises are of two types
1. OUTDOOR NOISES:
These noises have their sources of origin outside the room or
building , such as road traffic , railways , aero-planes , lifts , loud
speakers etc.
2. INDOOR NOISES:
These noises have their source of origin inside the room or building ,
such as conversation of the occupants , foot steps , banging of
doors , shifting of furniture , in water closets , working of
typewriters , gramophones etc.

7. TYPES OF SOUND INSULATING
MATERIALS :-
1. Glass mineral wool
2. Rock mineral wool
3. Foamed plastic
4. Quiet batt
5. Studio pro

8. GLASS MINERAL WOOL:-
 Glass mineral wool is made from sand and
recycled glass , limestone and soda ash .
 The glass is spun to form millions of the fine
strands of wool .
 A resin is used to bind the wool together to
form a mat .
CHARACTERISTICS –
 Long strands giving the product determine good
tear strength
 Non – combustible
 Light weight
 Available in rolls and slabs
USES –
 Loft insulation
 Cavity Wall Insulation
 Sound Insulation Within Partition And Floors .

9. ROCK MINERAL WOOL:-
 Rock mineral wool is made from volcanic rock , typically
basalt and / or dolomite .
 An increasing proportion is now recycled material from
slag ,a waste product from blast furnaces . The
materials are melted and then spun into fine strands of
wool .resin is used to bind the wool .
CHARACTERISTICS –
 High compressive strength suitable for high temperature
.
 Non – combustible
 Denser than glass mineral wool .
 Available in slabs , rolls and mattresses
 High compressive strength .
USES –
 Thermal insulation of flat roofs , rain screen façade and
external wall insulation .
 Fire protection of structural steel including smoke and
fire barriers .
 Insulation for floors and walls .

10. FOAMED PLASTICS :-
 Extruded polystyrene is made by mixing polystyrene
pellets with various ingredients to liquify them .
 A blowing agent is then injected into the mixture ,
to form gas bubbles .
 The foaming liquid is then forced through a shaping
die .
 When cooled it produces a closed cell foam that is
rigid and moisture resistant .
CHARACTERISTICS –
 Light weight
 High compressive
 Excellent water resistant
 Available in large board sizes
USES –
 Ground floors insulation
 Flat roofs insulation
 Heavy duty floor insulation

11. QUIET BATT :-
 It absorbs sound within exterior and interior
wall , ceiling , and attic cavities .
 It is a high performance sound absorbing and
thermal insulation product .
 Quiet batt acoustic insulation acoustically
outperforms standard fiberglass , rock wool ,
cellulose and foam insulations .
USES –
 Used in residential , home office , home
theatre
 Also used in commercial places like auditorium
, restaurant , food preparation , broadcast
studio , recording studio .

12. STUDIO PRO :-
 It is designed to absorb sound generated at low , mid
and high frequencies , studio pro .
 Class A studio foams are professional grade products used
residentially and commercially .
 A flammability rating use studio pro class A studio foams
in environments where sparks or other hot materials may
come into contact with acoustic product , or in areas
where crowds gather .
USES –
 It is used in commercial buildings like auditorium ,
gymnasium , restaurant , broadcast studio , recording
studio , theater , residential apartment / condo , multi
family dwelling .
 Used in institutional buildings like educational building
,sanctuary , museum / library .

13. IS SOUND INSULATION NECESSARY ?
 The most commonly recognized reason of
sound insulation is to stop sound from
bothering other people in the house or other
people outside the room and the house /
building .
 Sound is transmitted through most walls and
floors by setting the entire structure into
vibration .
 The higher the transmission loss of wall , the
better it functions as a barrier to the
passage of unwanted noise .
 Sound proofing is the process of developing
acoustic treatments to suppress , reflect ,
diffuse or absorb sound waves either at the
source using products such as baffling or
insulation on automotive engines , pipes /
ducting or machinery rooms .

14. METHODS OF ABSORPTION OF
SOUND :-

15. FROM THE VIEWPOINT OF ANALYSIS OF SOUND
INSULATION PROBLEMS , THE NOISE ARE AGAIN
CLASSIFIED INTO TWO TYPES:-
1. AIR – BORNE NOISES / SOUNDS :
It is generated in the air and is transmitted through the air directly to
the human ear . This types of sound travels directly from one part to
another through small gaps or openings or by vibrating the partition
walls or doors .
2. STRUCTURE – BORNE NOISES / SOUNDS :
They originate and progress in the building structure . It is caused by
impact and transmitted as air – borne noises .

16. ACOUSTIC PROPERTIES OF
BUILDING MATERIALS :
 Mass and rigidity property are the two factors that make a
material to be highly noise resistant .
 The concrete wall is highly efficient than masonry . Masonry
material made floor or wall do perform appreciably .
 Massive materials like stone , concrete can stop high sound waves
that are less resistant to less massive materials .
 Concrete slabs do perform good in the sound insulation activity
.woods are less dense than masonry and hence have smaller
performance in sound isolation .

17. ACOUSTIC PROPERTIES OF
BUILDING MATERIALS :
 Foam , fiberglass , rock wool etc. Can be considered as the
insulating materials we are familiar .
 The known materials are vinyl , neoprene etc. These
materials are used to make low cost economical acoustical
devices .
 Steel is one of the best material for sound insulation .
 Glass have the property to absorb more sound waves
instead of reflecting .

18. ACOUSTIC PROPERTIES OF BUILDING :
 Acoustic property of building is based on acoustic nature of building materials and
how sound is transmitted through the adjacent structural elements .
 The building must possess good sound insulation property to have good acoustic
feature .
 Sound insulation of buildings is a property that must be considered in the initial
stages of planning .
 For a good conventional office building construction , the sound insulation is
experienced good when it is in range of 45db .
 One must keep in mind that sound insulation gives the property of how much
sound is lost and the sound regained within the room .

19. TECHNIQUES TO REDUCE UNWANTED
SOUND IN BUILDINGS :
 Room arrangement
 Use of solid walls
 Planning for single storey
houses
 Proper arrangement of
balconies
 Having courtyards

20. 1. ROOM ARRANGEMENT IN BUILDING FOR NOISE
CONTROL-
 Considering the rooms in a
building based on less sensitive
room (kitchen , bathroom)
and more sensitive
room(bedrooms , living room)
.
 The arrangement of rooms
must be made in such a way
that more sensitive rooms are
away from the noise and less
sensitive rooms are towards or
close to the noise source .

21. 2. USE OF SOLID WALLS IN BUILDINGS FOR NOISE
CONTROL-
 The use of solid walls means , to use a
wall with fewer openings .
 Mostly walls used in building construction
are masonry . When it comes to high –
rise , concrete walls are used .
 Now having an opening in walls will reduce
its efficiency in noise control .
 The openings in the forms of windows or
doors that are facing directly towards the
noise , would welcome noise into the
building .
 In the image the wall barrier between the
building and the noise is not an adequate
height , but the lower floors must feel
comfortable with less noise . This is
possible because the barrier has no opening
.

22.  This is an architectural planning step
taken before planning the design of
the building .
 The plan is to construct a two –
storey building . We also have a
barrier in between the site and the
noise source . The situation is that
the reduction of noise from the
source is efficient only when the
building is a single storey building is
planned , the barrier height will be
sufficient .
 Under such situation , it is always
recommended to compromise with the
plan and go for an economical and
quality construction .
 Another option is to adopt a split –
level design for the building , that
would meet all the requirements .
3. PLANNING OF SINGLE STOREY HOUSES-

23. 4. PROPER ARRANGEMENT OF BALCONIES FOR NOISE
CONTROL-
 Balconies provide access to the
external environment as well as
ventilation in the form of light and
air . But the improper arrangement
of balconies would give complete
discomfort , hiding all its advantages
through noise .
 Balconies have higher exposure to
outside environment . If the building
is faced towards a highly traffic
prone area , with balcony facing the
same side , it would promote the
intensity of noise entering the
building .Balconies can be placed in a
shielded area than direct open area .

24. 5. HAVING COURTYARDS FOR NOISE CONTROL-
 Having courtyards helps in reduction
noise control in buildings . This can be
an added measure of noise reduction
in architectural planning and design .
 The proper architectural design may
also provide for noise reduction in an
area outside of the building .
 They provide an acoustical privacy .
 A shielding effect is provided by these
courtyards . It is constructed in
residences , schools , hospitals ,
colleges etc .