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IOP Conference Series: Earth and Environmental Science
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Practical Study to Find the Best Sound Insulation
for Walls From Different Building Materials
To cite this article: Khalid Ahmed Salih et al 2022 IOP Conf. Ser.: Earth Environ. Sci. 1060 012031
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ISAESC-2022
IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
IOP Publishing
doi:10.1088/1755-1315/1060/1/012031
1
Practical Study to Find the Best Sound Insulation for Walls
From Different Building Materials
Khalid Ahmed Salih1, Aktifaa Salih Khudhur2 and Aziz Ibrahim Abdulla3
1-3 Collage of Engineering, Environmental Engineering Department, Tikrit University,
Iraq.
1Email: engineer.khalid.salih@gmail.com
2Email: ektifaasalih@gmail.com
3Email:Lan914@gmail.com
Abstract. The sound insulation of walls made of different building materials was tested in
various places from Tikrit University in Iraq, with a number of up to 14 walls, distributed in
the Department of Environmental Engineering, the Department of Civil Engineering and
Chemical Engineering, the Deanship of the College of Arts, the College of Education, the
College of Arts, the Department of Psychology, and the Deanship of the College of Computer.
It was found through the results that the highest value of sound insulation was obtained for the
wall of sequence 13, which amounted to 44.86 dB, but it is for a wall built of thermiston
material, and this indicates that thermiston gave the greatest value for sound insulation. The
study showed that there are building materials for other walls that can give excellent sound
insulation, which is a material republican bricks covered with wood and walls built of
sandwich material with a thickness of 10 cm and walls concrete coated with PVC, as well as
sandwich walls with a thickness of 7 cm, reaching. The highest values for the rest of the sound
insulation results for the top five values were (38.6, 38.43, 37.13, 34, 33.76) dB decibel. The
results showed that the perforated brick is no doubt excellent sound insulation and proof of that
all the walls built of perforated bricks provided insulation Excellent sound with the rest of the
additional isolators used. The study also showed that for the walls of the sandwich panels, with
the increase in thickness, the value of sound insulation increases. Where the value of sound
insulation (38.43 dB, 34 dB and 30.36 dB) for walls with thickness (10cm, 7cm and 5cm)
respectively. Finally, it is important to mention that the lowest value of the measured sound
insulation for measured walls was 23.23 decibels, but for a brick wall from the outside of the
squirt spreading cement and from the inside with plaster and borax in the College of
Engineering - Department of Environmental Engineering building.
Keywords. Sound insulation, Walls insulation, Buildings noise.
1. Introduction
Sound insulation is one of the important design criteria in buildings because of this property's direct
impact on human comfort, and it has been noticed recently that there is great interest in reducing the
impact of noise sources resulting from the increase in means of transportation and the use of
mechanical equipment in power generation [1] and that noise has effects Many and dangerous to
human health, as they cause serious diseases, including permanent or temporary hearing loss, chronic
ISAESC-2022
IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
IOP Publishing
doi:10.1088/1755-1315/1060/1/012031
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high blood pressure and stroke, especially when exposed to a sudden high level of noise [2]. Sound is
absorbed through the air, walls, ceilings, floors, furniture and people. The amount of sound absorbed,
polished, smooth, solid and impermeable materials are heavy in weight, so their sound absorption is
less than materials with rough, porous surfaces and light weight plastic [3].
Sound insulation can be defined as controlling the level of noise reaching one of the rooms from the
other rooms or from outside to inside, where the sound is transmitted from one room to another
through the sound generated in the air through the walls [2]. Another definition of sound insulation is
that it is a group of The methods and methods used in order to reduce the intensity of the sounds
affecting the buildings. This mechanism is done by using a group of materials, knowing that sound
insulation has been included in many building plans to reduce noise and disturbance in industrial
environments or offices and homes [4]. The effect of sound pollution can be summed up by:
1. Impact on hearing: Hearing loss is considered one of the immediate and acute effects of sound
pollution on humans, as continuous and long periods of exposure to noise may damage the
eardrum and thus cause permanent hearing loss.
2. Impact on public health: Sound pollution causes many harmful health effects, most notably:
anxiety, stress, headaches, nervousness, in addition to the constant feeling of fatigue, thus
reducing productivity and work efficiency, which may lead to serious consequences over time
[5].
It is a requirement for sound insulation, improves insulation as the mass of the insulating material
increases, no openings as openings in the walls reduce insulation and Intermittent or multiple
constructions such as double windows.The researcher [6] indicated that to find the efficiency of sound
insulation in buildings, the insulation is calculated for a frequency of 200 Hz and then for a frequency
of 1000 Hz, and the sound insulation should not be less than 40 decibels for both cases. The researcher
[7] showed that buildings that contain pores make the movement of air through them possible and
increase sound absorption by converting sound energy into heat by friction. He also stressed that the
presence of gaps also affects the relationship between sound insulation and the density of the cutter, as
the gap increases the sound insulation. The researcher [8] studied the acoustic insulation of Reed-
Cement Boards using a practical device, and its results were compared using glass panels with data
from previous research, and the difference did not exceed (3) decibel dB . The researchers [9] studied
the sound insulation test for a group of concrete models and added three materials to the concrete in
different proportions for each model to improve the sound insulation property of the concrete. These
materials are rubber (rubber) and two types of stones, namely (lapillus) and ( pumice), and they
concluded that increasing the proportion of stones, i.e. the following materials (lapillus) and (pumice)
leads to an increase in sound insulation and a significant increase in the sound transmission loss of
concrete for all frequencies . The researchers concluded [10] that the sound design has an influential
necessity in the design act, especially when designing specialized halls, and that neglecting this aspect
in the design leads to the lack of sound in most of the built halls, especially classrooms, and there are
factors that affect the sound level and its frequency, including noise sources. And the acoustic
properties of the materials for walls and ceilings. The researchers [11] showed that noise has many and
dangerous effects on human health, as it causes serious diseases, including permanent and temporary
hearing loss, chronic high blood pressure and stroke, especially when exposed to a sudden and high
level of noise, such as explosions, and sometimes leads to death.
2. Material and Method
The Material and method of work has been clarified in the field study that included the selection of
many walls with different types in Tikrit university in Iraq. Types of walls to be studied It can be
summarized in the following types:
1. Brick walls
2. Walls built of block material
3. Walls sheathed with wood material
4. Walls coated with plastic material
5. PVC walls
6. Ready-made concrete casting walls
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IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
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doi:10.1088/1755-1315/1060/1/012031
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2.1. Equipment and Tools Concerning the Study
First, a measuring device for sound intensity in decibels, rather than dB, with two measuring devices
at the same time BENETECH GM1351- model(Digital Sound Level Metar).
Figure 1. Sound intensity meter.
Secondly, the audio device which was manufactured locally, the audio Components includes:
1. A wheel for the wire connecting to the beginning of the weight to pass through.
2. An iron pipe tube with a diameter of approximately 5 inches and a length of 60 cm.
3. Supports and they are of two types: A- An equilateral angle with a length of 60 cm, B- An
equilateral angle with a length of 25 cm
4. A weight with a diameter of 2.5 inches and a length of 25 cm, and its end is convex in order
for the sound to be concentrated in one area and with the same sound strength previously
recorded. Figure 2 shows the audio device with the parts' markings.
5. Square plate 2.5 mm thick, one side 40 cm long
6. A weight of 1 kg and a half is attached to the wire.
7. A wire with a length of 1 meter in order to connect to the beginning of the weight and pass
through the wheel so that the wire is stretched to a specific size and then left to make a sound
by the weight.
Figure 2. The audio device Components.
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IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
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doi:10.1088/1755-1315/1060/1/012031
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2.2. Study Area
The University of Tikrit was chosen as a study site for this project, where the sound insulation of the
walls of different buildings was studied in various places in the university, where 14 walls were
chosen in various locations of the university, and the table (1) shows in detail the locations where the
measurements were made with all the details Wall type and wall thickness.
Table 1. The walls that have been studied.
No.
Site name
The type of wall that was
measured
Wall thickness
(cm)
Notes
1
Environmental Engineering Department
-
Discussion room No. 1
wood-coated bricks
24 cm, fully laminated, half-
sided
wrapping
34cm
2
Environmental Engineering Department
-
Discussion room No. 1
Bricks from the outside of the
plastering
cement, and from the inside
whites and blazes
25cm
3
Environmental Engineering Department
sandwich panel wall
width 5 cm
5cm
4
The large building of the model halls
In the College of Engineering
laminated brick wall
On the one hand, stone
Side
plaster and borax
24cm
5
Engineering department head room
The environment
brick wall
PVC coated
The other side is plaster
and blessed
25cm
6
Engineering department course room
The environment
brick wall
from outside to squirt
scattering cement and from
Interior with plaster and borax
24cm
7
Classrooms on the floor
First- Department of Environmental
Engineering
brick wall
from outside wrapped
sandwich panel
25cm
8
Classroom in the department
civil engineering
concrete wall
ready-made from one side
PVC
29cm
9
Classroom in the department
chemical engineering
concrete wall
ready
28cm
10
Deanship of the College of Arts
inner wall of
bricks from outside
Plaster and borax as well
from the inside
25cm
11
College of Education - Department of
Science of
psychology - Classrooms
A wall made of sandwiches
panel
10cm
12
The large building of the model halls
In the College of Engineering
Republican brick wall
wrapped inside
Wood
25cm
13
Deanship
College of Computer Science
wall of material
Thermiston finish it off
The outside of the squirt with
cement
And from the inside is plaster
and blessed
35cm
14
College private halls
Law
A wall made of sandwiches
panel
7cm
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IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
IOP Publishing
doi:10.1088/1755-1315/1060/1/012031
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2.3. Standard Noise Levels
Noise levels are very important in determining the measurement of acoustic insulation of walls in
terms of the appropriateness of the insulation and its acceptability in accordance with international
standards and laws [`12].
Table 2. Shows the permissible noise levels in the city, according to international and local standards,
in Decibel (dB).
The location
Permissible Level (dB)
Factories
85
Building site
70
Small workshops
60-70
Work offices
32-63
Transportation
68
Quiet abode
35
Near hospitals
30
Theatres, cinemas and music halls
20-30
Reading room or library
20-30
Lecture room, meeting room
20-30
General store, quiet restaurant
40-50
Secretarial room
40-50
Table 3. Shows the effect of noise on the sense of hearing.
Noise level in decibel ( dB)
The effect on the sense of hearing
70-80
Decreased sense of hearing
90-120
Hassle
100 and more
Severe pain in the ear - possible rupture of the eardrum
The values that will be obtained from the field work of this study are checked in table (2) and table
(3), and the noise whose values will be recorded are classified compared to the above tables.
2.4. Measuring Method
1. Measure the intensity of sound passing through the wall using a sound intensity meter in decibel
dB.
2. Two devices are used to measure the intensity of sound of one type at the same time.
The two devices are placed on both sides of the wall with a known distance of one and a half meters.
A fixed sound is cast to all walls using a manufactured device that is placed half a meter from the wall
to be measured. The sound intensity is recorded in decibels using two sound intensity meters at the
same time. The sound-emitting device is made of iron and has a weight. The weight is dropped
vertically, freely at a known fixed height, about 85 cm, on an iron plate attached to the device and to
all the walls. Three readings were taken for each device and each site, and then the average of these
readings was taken, and the same method was applied to the other device on the other side at the same
time, and with two devices for measuring the intensity of sound, the number of readings taken for one
wall becomes equal to six readings. Figure (3) shows a simplified diagram of the method of measuring
the sound insulation of walls, while figure (4) shows a picture of measuring the sound insulation of
walls in the College of Education - classroom in the department of psychology.
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Figure 3. Shows a simplified diagram of the method of measuring the acoustic insulation of walls.
3. Results and Discussion
3.1. Sound Insulation Results for Measured Walls
Table 4. Illustrated sound insulation results for measured walls.
No.
The type and details of the studied
walls
Sound intensity
readings
Measured in decibels
(dB)
Reading rate in
decibels
(dB)
Sound insulation in
decibels (dB)
1
Fully laminated side bricks
wood half side
Wood Packaging - Engineering
Department
Environment - discussion room
no. 1
-First 108.7 out
70.1 inside
-second 108.7 out
70.0 inside
-Third 108.7 out
70.1 inside
First 108.7 Abroad
second 70.1 inside
38.6
2
Bricks from the outside of the squirt
cement, and from the inside
Plaster and Plaster - Section
Environmental Engineering – Hall .
Discussions no.1
-First= 110 out ,
=83.9 inside
-Second=109.7 out ,
=83.8 inside
-Third =109.7 out , =
83.9 inside
First 109.8 Abroad
second 83.86 inside
25.94
3
Sandwich panel fish thick
-5 cm classroom-
Environmental Engineering
Department
First 100.0 out
75.1 in
Second 109.8 out
77.2 inside
Third 109.9 out
76.3 inside
First 106.56 Abroad
second 76.2 inside
30.36
4
laminated brick wall
stone side and side
Other plaster and borax
The large hall building
Model - College of Engineering
First 109.7 out
76.3 inside
second 110.0 out
76.3 inside
Third 109.7 out
76.4 inside
First 109.8 Abroad
second 76.3 inside
33.5
5
Brick wall
PVC coated
The other side is plaster
And Burke's room for the head of
the department
engineering
First 108.7 out
86.3 inside
second 108.9 out
86.3 inside
Third 108.6 out
84.0 in
First 108.73 abroad
second 85.5 inside
23.23
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doi:10.1088/1755-1315/1060/1/012031
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No.
The type and details of the
studied walls
Sound intensity
readings
Measured in decibels
(dB)
Reading rate in
decibels
(dB)
Sound insulation in
decibels (dB)
6
Brick wall
from outside to squirt
Cement scattering from the inside
Plaster and borax - prescriptive
Environmental Engineering
Department
First 100 out
83.8 in
Second 109.5 out
83.5 inside
Third 109.6 out
83.6 inside
First 106.36 Abroad
second 83.6 inside
22.76
7
Sandwich panel wall thick.
5cm - Classrooms
On the first floor-section
Environmental Engineering
First 106.7 out
77.1 inside
second 107.4 out
78.5 in
Third 108.7 out
77.9 inside
First 107.76 abroad
second 77.83 inside
29.77
8
concrete wall
ready made one side envelope
PVC Classroom- Section
civil engineering
First 108.7 out
75.3 in
second 108.7 out
74.3 inside
Third 108.9 out
75.4 inside
First 108.76 abroad
second 75.0 inside
33.76
9
concrete wall
prefab classroom in
Department of Chemical
Engineering
First 107.6 out
81.3 in
Second 109.7 out
83.3 inside
Third 108.7 out
83.4 in
First 108.67 abroad
second 82.67 inside
26.0
10
Brick wall of
The outside is plaster and borax as
well
Inside - Deanship of the College
Literature
The first 105 out
79.9 inside
Second 109.7 out
80.8 in
Third 109.9 out
82.9 inside
First 108.2 abroad
second 81.2 inside
27.0
11
A wall made of sandwiches
Panel of the College of Education -
Department
Psychology - halls
study (thickness 10cm)
First 108.7 out
69.3 inside
Second 107.9 out
70.3 in
Third 109.7 out
71.4 in
First 108.76 abroad
second 70.33 inside
38.43
12
Republican brick wall
Wood wrapped inside
The large building of the halls
Model - College of Engineering
First 110.0 out
72.8 in
second 108.6 out
73.1 inside
Third 109.7 out
71.0 in
First 109.43 abroad
second 72.3 inside
37.13
13
Wall of thermostone
Finish it from the outside to squirt
with cement and from
The interior is plaster and bore /
deanship
College of Computer Science
First 109.3 out
66.3 inside
second 108.5 out
62.3 inside
Third 108.8 out
63.4 in
First 108.86 abroad
second 64.30 inside
44.86
14
A wall made of sandwiches
PANNEL - Faculty of Law
( thickness 7cm )
First 102 out
72 inside
second 108.6 out
73 inside
Third 109.9 out
73.5 in
First 106.83 Abroad
second 72.83 inside
34
3.2. Method Used to Calculate Sound Insulation
According to the results obtained in table (3) above, the method of calculating the sound insulation in
decibels rather than dB is represented by the product of subtracting the rate of the first reading from
the rate of the second reading and the result represents the sound insulation provided by the wall in
ISAESC-2022
IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
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doi:10.1088/1755-1315/1060/1/012031
8
decibels rather than dB, and the following is a model for calculating the sound insulation for wall with
serial number 1
(Sound insulation) of the wall sequence 1 = rate of first reading - rate of second reading
(Sound insulation) of the wall sequence 1 = 108.7 – 70.1 = 38.6 dB
Figure 4. Shows A picture to measure the sound insulation of walls in one of the classrooms in the
College of Education with the reading of the device.
Figure 5. Pictures showing the measurement of the sound insulation of walls of ready-made concrete
in the Department of Chemical Engineering.
3.3. Discuss the Results in A general Way
From observing the results obtained and shown in Table (4), it is clear that the highest value of sound
insulation was obtained for the wall of sequence 13, which amounted to 44.86 dB, but by reference to
the same table (4) it appears that the type of the measured wall is a wall of thermiston material,
finished from the outside with cement, and from the inside with plaster and borax material. This
ISAESC-2022
IOP Conf. Series: Earth and Environmental Science 1060 (2022) 012031
IOP Publishing
doi:10.1088/1755-1315/1060/1/012031
9
indicates that thermiston gave the highest value for sound insulation, and this leads to that this material
is characterized by providing high sound insulation.
Some other important results for the Sound insulation values that obtained and clarified in table (4)
were equal to (38.6, 38.43, 37.13, 34, 33.76) and these values represent the walls of the sequence (1,
11, 12, 14, 8). ) respectively in the table (4), and the six highest values obtained for the sound
insulation of the walls can be represented in the following table (5) .
Table 5. The six highest values obtained for the sound insulation of the walls.
No.
The type of the studied wall
Highest values for sound
insulation
Measured in decibel (dB)
1
Wall of thermostone
Finish it from the outside to squirt with cement and from
The interior is plaster and bore / deanship College of Computer
Science
44.83
2
Fully laminated side bricks
wood half side Wood Packaging -
Engineering Department
Environment - discussion room
no. 1
38.6
3
A wall made of sandwiches
Panel of the College of Education - Department
Psychology - halls
study (thickness 10cm)
38.43
4
Republican brick wall
Wood wrapped inside
The large building of the halls
Model - College of Engineering
37.13
5
Wall of Thermostone - College of Law
34
6
concrete wall
ready-made from one side
PVC Classroom- Section
civil engineering
33.76
In table (5), it is clear that the wall sheathed with wood gave the second highest value for sound
insulation, as it was equal to (38.6) dB. This indicates that wood material is an excellent sound
insulation material.
The third largest value of acoustic insulation was for a wall made of sandwich panel, where the value
of the acoustic insulation was (38.43) dB. This is conclusive evidence that the sandwich panel can
provide very good sound insulation. The highest value of sound insulation in the fourth sequence was
for a wall made of republican bricks coated on one side with wood material, where the sound
insulation value reached (37.13) dB, and this is further evidence that wood material can provide
excellent sound insulation as it was the second highest value Also for a wall sheathed with wood, but
for two sides. The fifth highest value was for a wall of sandwich with a thickness of 7 cm, which was
equal to (34) dB. The last value, which is the sixth in table (5), was for a ready-made concrete wall
covered with PVC on one side, where the sound insulation value was (33.76) dB, but this leads to the
fact that plastic can provide very good sound insulation for the wall coated with it. The six highest
values of sound insulation were selected in table (5), and it is possible that perforated bricks are
undoubtedly an excellent sound insulator, and the evidence for this is that all walls built of perforated
bricks provided excellent sound insulation results with the rest of the additional insulators used.
3.4. Discussion of the Results of Acoustic Insulation of Sandwich Panels Walls
The measurements were made for the walls of the sandwich panel material. Table (4) shows the rates
of sound insulation values for the types of sandwich panels that were obtained.
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doi:10.1088/1755-1315/1060/1/012031
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Figure 6. Values of sound insulation of sandwich panels walls.
It is clear from figure (6) that the highest average value of the sound insulation values for the types of
sandwich panels that were obtained was for a wall thickness of 10 cm, which amounted to 38.43 dB,
while the value of the sound insulation rate for a wall thickness of 7 cm was equal to 34 dB, and
finally it reached The value of the sound insulation rate measured for a wall thickness of 5 cm is 30.36
dB. This indicates that the value of the thickness affects the value of the sound insulation of the
sandwich panel walls, and if greater measurements were available, the insulation would have been
higher, meaning that the relationship is direct between the thickness and the measured sound
insulation.
Conclusions
1. The highest sound insulation value was obtained for the wall of sequence 13, which amounted
to 44.86 dB, but it is for a wall built of thermiston material, and this indicates that thermiston
gave the greatest value for sound insulation.
2. The walls built of bricks covered with wood and covered with PVC plastic, as well as concrete
walls covered with PVC plastic with a thickness of 10 cm, and the walls made of sandwich
panel material gave high values for sound insulation.
3. The use of porous bricks that contain holes is a good example of providing excellent sound
insulation with the rest of the additional insulators used from PVC and others.
4. For the walls of sandwich panels, it was found that with increasing thickness, the sound
insulation value increased, as the sound insulation value reached (38.43 dB, 34 dB and 30.36
dB) for walls with thicknesses (10 cm, 7 cm and 5 cm), respectively.
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