Pokhara Engineering College

Department of Architecture
NOISE & ITS IMPACT and SOUND INSULATION
 CONTENTS
Noise and its Impact
1. Types of noise
2. Noise impact to human being
3. Noise control techniques

Sound Insulation
1. Mass law
2. Vertical barrier- wall & partition
3. Horizontal barrier- floor and ceiling
 Noise
• Any unwanted sound that causes disturbance in our ear
• Noise > Physically 60 dB sound in normal condition
• Psychologically, one man’s music may be others noise if
person do not like it
• It may be due to the frequency of sound or intensity of
sound or both.
• Noise due to high frequency is more unpleasant than
the noise due to low frequency sounds.
Sources of Noise in Buildings
 Types of Noise
External noise

• Noise from outside

• Noise from road traffic, airplane, machinery, train,
construction works, workshop, factory etc.
• Can be reduced by natural & artificial barriers
 Types of Noise
External noise
 Types of Noise
External noise
 Types of Noise
Internal noise

• More internal sound inside buildings

• Noise from conversation of people, radio, TV, musical
instruments
• Noise from footsteps, furniture movements, slamming
of doors, cistern, dropping of utensils on floor, etc
• Very sharp sound
 Types of Noise
Internal noise
 Types of Noise
Internal noise
 Noise impact to human being
• Noise pollution is emerging as one of the major
problems in urban areas in the world
• Noise & noisy condition - harmful to human being
• Causes uncomfortable living condition in daily life,
various physical and mental problems
 Noise impact to human being
The WHO has documented seven categories of adverse
health effects of noise pollution on humans.

1. Hearing Impairment
• Hearing is essential for well-being and safety.
• Hearing impairment is typically defined as an increase
in the threshold of hearing as clinically assessed by
audiometry.
 Noise impact to human being
2. Interference with Spoken Communication
• Noise pollution interferes with the ability to comprehend
normal speech and may lead to a number of personal
disabilities, handicaps, and behavioral changes.
• These include problems with concentration, fatigue,
uncertainty, lack of self confidence, irritation,
misunderstandings, decreased working capacity, disturbed
interpersonal relationships, and stress reactions.
• Some of these effects may lead to increased accidents,
disruption of communication in the classroom, and
impaired academic performance
• Particularly vulnerable groups include children, the
elderly, and those not familiar with the spoken language.
 Noise impact to human being
3. Sleep Disturbances
• Uninterrupted sleep is known to be a prerequisite for
good physiologic and mental functioning in healthy
individuals.
• Environmental noise is one of the major causes of
disturbed sleep
• When sleep disruption becomes chronic, the results are
mood changes, decrements in performance, and other
long-term effects on health and well-being
• Much recent research has focused on noise from aircraft,
roadways, and trains
• Noise during sleep causes increased blood pressure,
increased heart rate, increased pulse amplitude,
vasoconstriction, changes in respiration, cardiac
arrhythmias, and increased body movement
 Noise impact to human being
4. Cardiovascular Disturbances
• Noise can trigger both endocrine and autonomic nervous
system responses that affect the cardiovascular system and
thus may be a risk factor for cardiovascular disease
• Acute exposure to noise activates nervous and hormonal
responses leading to temporary increases in blood pressure,
heart rate and vasoconstriction
• Even though the increased risk for noise-induced
cardiovascular disease may be small, it assumes public
health importance because both the number of people at
risk and the noise to which they are exposed continue to
increase
 Noise impact to human being
5. Disturbances in Mental Health
• Noise pollution is not believed to be a cause of mental
illness, but it is assumed to accelerate and intensify the
development of latent mental disorders
• Noise pollution may cause or contribute to the following
adverse effects: anxiety, stress, nervousness, nausea,
headache, emotional instability, argumentativeness,
changes in mood, increase in social conflicts, neurosis,
hysteria, and psychosis
• Noise levels above 80 dB are associated with both an
increase in aggressive behavior and a decrease in behavior
helpful to others
 Noise impact to human being
6. Impaired Task Performance
• The effects of noise pollution on cognitive task
performance have been well-studied.
• Noise pollution impairs task performance at school and at
work, increases errors, and decreases motivation
• Reading attention, problem solving, and memory are
most strongly affected by noise
• Cognitive and language development and reading
achievement are diminished in noisy places
 Noise impact to human being

7. Negative Social Behavior and Annoyance Reactions

• Annoyance is defined as a feeling of displeasure

associated with any agent or condition believed by an

individual to adversely affect him or her. Perhaps a better
description of this response would be aversion or distress.
• Annoyance increases significantly when noise is

accompanied by vibration or by low frequency components

 Noise impact to human being
Some other physical and mental problems which can be
related with above points are as follows:

1. Creates discomfort in daily social life

2. Disturb for rest, peace & concentration
3. Adverse effect in blood pressure, muscular pain,
unsleeping, tension, headache,
4. Decreases working efficiency of person
5. Cause physiological disorder i.e. digestive, respiratory,
blood circulation & nervous system
6. Also effect the growth of children
7. Takes away essence of music & speech
 Noise impact to human being
8. Also effect to cattle & poultry growth i.e. decreases
milk & egg production
– a research in India shown , with hearing pleasing
music, cattle also give more milk than ordinary
condition
9. Prolong exposure to noise may cause temporary
deafness & sudden noise i.e. loud explosion may cause
ear damage
• > 65 dB – psychological & physiological effect( nervous,
mental & body fatigue)
• > 90 dB – continue noise cause permanent hearing loss
• > 100 dB –short time noise cause damage of ear organ
• > 120 dB – cause pain & hearing loss
Noise impact to human being
Noise Control Techniques
 Noise control techniques
a. Noise control techniques for external noise

1. Urban planning according to noise level

2. Orientation, planning & designing of a building

3. Noise screening – Natural & artificial

4. Sound reduction by construction technology

b. Noise control techniques for internal noise

 Urban planning according to noise level
Deals with urban planning & design according to
acceptable noise level by architects and planners
1. 80 dB - Industrial & transportation zone for factory,
airport, bus station
 Urban planning according to noise level
Deals with urban planning & design according to
acceptable noise level by architects and planners
2. 70dB - public & commercial zone for office, market
 Urban planning according to noise level
Deals with urban planning & design according to
acceptable noise level by architects and planners
3. 60dB - residential zone for residence, apartment, hostel,
hotels
 Urban planning according to noise level
Deals with urban planning & design according to
acceptable noise level by architects and planners
4. < 50 dB - noise control special zone for hospital, school,
college, library, meditation centre, religious complex, resort
etc

Royal Liverpool hospital

 Urban planning according to noise level
Deals with urban planning & design according to
acceptable noise level by architects and planners
5. Planning airport, train & bus station far away from core
city area i.e. International airport > 25 km ( Heathrow,
Indira Gandhi airport)
 Urban planning according to noise level
Deals with urban planning & design according to
acceptable noise level by architects and planners
Orientation, planning & designing of a building
a. Distance from noise source

b. Orientation of building & openings away from noise

c. Creation of buffer space

Orientation, planning & designing of a building
a. Orientation of building & openings away from noise
Orientation, planning & designing of a building
a. Orientation of building & openings away from noise
Orientation, planning & designing of a building
b. Distance from noise source
Natural screening by vegetation, trees, land etc
Orientation, planning & designing of a building
b. Distance from noise source
Natural screening by vegetation, trees, land etc
Orientation, planning & designing of a building
b. Distance from noise source
Orientation, planning & designing of a building
b. Distance from noise source
Artificial screening by walls, reflectors etc
Orientation, planning & designing of a building
b. Distance from noise source
Artificial screening by walls, reflectors etc
Orientation, planning & designing of a building
b. Distance from noise source
Artificial screening by walls, reflectors etc
Orientation, planning & designing of a building
c. Creation of Buffer Space

Room arrangement in buildings for noise control

• Considering the rooms in a building based on sensitivity,
we can divide into less sensitive rooms and more
sensitive room. Now less sensitive rooms are the kitchen,
bathroom etc. More sensitive rooms are bedrooms,
living rooms.
• The arrangement of rooms must be made in such a way
that more sensitive rooms are away from the noise and
the less sensitive rooms are toward or closer to the
noise source.
Orientation, planning & designing of a building
Room arrangement in buildings for noise control
• For example in the following figure of planning a
residential building.
• As per the concept of arrangement the kitchens and
bathrooms were placed near to the expressway and the
bedrooms, living rooms where keep way from it. Thus,
more sensitive rooms get a shielding effect (buffer zone).
Sound reduction by construction technology
• For noise reduction through cavity wall, floor, roof,
partition, openings
• Multilayer construction of wall, floor, roof, partition, etc
• Using sound absorbent in the surface
• Using sound insulation inside wall, floor, roof, partition,
etc
• False ceiling, mansard roof as buffer space
• Double / triple glazed openings
• Acoustic door & window ( theatre)
• Suspended floor
Sound reduction by construction technology
Sound reduction by construction technology
 Noise control technique for internal noise

• Reduction of noise source ( cistern, door slamming,

musical instrument etc)
• Isolate the noise source by covering surface ( carpet,

linoleum, parquet on floor etc)

• Placing noisy machinery in basement
• Separation of noisy space from quite space ie kit, garage

away from bed & puja

• Noise reduction through cavity wall, floor, roof, partition,
• Multilayer construction of wall, floor, roof, partition, etc
Noise control technique for internal noise
Sound Insulation
 Mass Law
• The insulation of massive wall depends upon mass per
unit area i.e. the insulation of sound increases with the
increase in the thickness of the wall.

• The insulation averaged over the frequencies of range

100-3150 Hz increased by about 5 dB for each doubling
of mass

• 110 Half brick wall - 45dB

• 230 Single brick wall - 50dB
Mass Law
Typical insulation values
 Vertical Barrier- Wall & Partition
1. Massive homogenous wall

• Stone, brick, concrete

masonry
• Plaster both sides better
• Insulation depends upon
mass law
• TL of 1 brick wall = 50 db
• TL of 1.5 brick wall = 53 db
 Vertical Barrier- Wall & Partition
2. Partition wall of porous
materials:

• Porous concrete insulate 10

% > than non porous rigid
materials
• Partition of non rigid porous
materials like felt, glass wool,
slag wool etc Offer low sound
insulation
• But combination with rigid
materials offer better
insulation
 Vertical Barrier- Wall & Partition
3. Double partition wall

• Consist of plaster or fiber

boards on both sides with
sound absorbing blanket in
between
• Use in radio, tv, music studio,
hall etc
 Vertical Barrier- Wall & Partition
4. Cavity wall
• Ideal construction for sound proofing
• Air gap between 2 leaves
• Filled with some resilient materials
• Especially need in theatre, cinema, conference hall,
music studio etc
 Horizontal barrier- Floor & ceiling
1. Use of resilent surface materials on floor

• Consists of soft floor finish

• Covering resilient materials
• Like vinyl tile, linoleum cork sheet, carpet, acoustic tile
• Damp impact noise = 5 - 10DB insulation
 Horizontal barrier- Floor & ceiling
2. Concrete floor floating construction

• Resilient materials like mineral quilt or glass wool laid

between RCC floor & screed
 Horizontal barrier- Floor & ceiling
2. Concrete floor floating construction
 Horizontal barrier- Floor & ceiling
3. Timber floor floating
construction

• Resilient materials like

mineral quilt or glass
wool
• Laid between timber
floor & timber sub floor
 Horizontal barrier- Floor & ceiling
3. Timber floor floating construction
 Horizontal barrier- Floor & ceiling
4. False ceiling

• Ceiling of acoustic panels

suspended below main
floor of rcc/ truss or any
roof or floor
• Create max. noise
insulation
• Especially use in hall,
office, shop etc.
Thank you...