Building science 2 _ Project 2 Report

BUILDING SCIENCE 2 [BLD 61303 / ARC 3413] PROJECT 2 : INTEGRATION PROJECT

SENTUL COMMUNITY LIBRARY REPORT & CALCULATION

NAME

: ID

TUTOR

CHOONG LAI MUN :

:

0313573 MR. AZIM SULAIMAN

TABLE OF CONTENT 1.0 Introduction 1.1 Objective 1.2 Project Description 1.3 Design Project Floor Plans 2.0 Lighting 2.1 Cafe 2.1.1 Daylight 2.1.2 Artificial Light 2.1.3 PSALI 2.2 Children’s Library 2.2.1 Daylight 2.2.2 Artificial Light 2.2.3 PSALI 3.0 Acoustic 3.1 External Sound Pressure Level 3.1.1 Cafe 3.1.2 Children’s Library 3.2 Reverberation Time (Children Library) 3.3 Sound Reduction Index (Café ) 4.0 References

1.0 INTRODUCTION 1.1

OBJECTIVE This project aims to integrate students’ understanding of the principles of lighting and acoustics in the context of the final design project of studio 5. It encompasses advanced daylighting systems and the integration of electrical lighting, strategies for noise management and room acoustics.

1.2

PROJECT DESCRIPTION The final design project of studio 5 is designing a community library within an urban infill site of Jalan Sultan Azlan Shah, Sentul, Kuala Lumpur. The design of the building is to consist of appropriate architectural responses that address the aspects of the urban street context and user behavioural patterns as discerned and analyzed in the preliminary studies.

1.3

DESIGN PROJECT FLOOR PLANS

LOWERGROUND FLOOR PLAN

MULTIPURPOSE AREA

PLAZA

CAFE

STREET GARDEN

UPPERGROUND FLOOR PLAN

CHILDREN’S LIBRARY

INFO COUNTER LOBBY

EXHIBITION AREA

LOBBY

FIRST FLOOR PLAN

DISUCSSION ROOM

MAIN COLLECTION DIGITAL STATION

RAEDING PAVILLION

QUITE READING

SECOND FLOOR PLAN

AUDITORIUM

COLLECTIONS

READING GARDEN

2.0 LIGHTING 2.1

Cafe 2.1.1

Daylight

According to MS 1525, Daylight Factor Distribution is as below: Zone Very Bright Bright Average Dark

Daylight Factor (%) >6 3-6 1-3 0-1

Distribution Very large with thermal and glare problems Good Fair Poor

The café of the community library is located on the lower ground floor of the building right underneath the grand stairs that lead to the entrance of the library. As the location of the café is covert, only the left side of the faç ade is exposed to sunlight. Thus, it does not have much direct sunlight, which will cause the space to be slightly dark. In order to solve the problem, other the wall facing the north, most of the walls are all covered with glass wall to allow maximum sunlight into the space. As there will be no direct sunlight, it would not cause much glare or thermal problem.

CAFE

Daylight Factor Calculation Floor Area (�2 ) Area of faç ade exposed to sunlight (�2 ) Area of skylight Exposed Faç ade & Skylight Area to Floor Area ratio/ Daylight Factor, DF

58.7 21.48 0 (13.5+0) 58.7

= 0.23 = 23% x 0.1 = 2.3%

Natural Illumination Calculation Illuminance 120,000 lux 110,000 lux 20,000 lux 1000-2000 lux 400 lux <200 lux 40 lux <1 lux Eexternal = 20 000 lux đ??¸

DF= đ??¸ đ?&#x2018;&#x2013;đ?&#x2018;&#x203A;đ?&#x2018;Ąđ?&#x2018;&#x2019;đ?&#x2018;&#x;đ?&#x2018;&#x203A;đ?&#x2018;&#x17D;đ?&#x2018;&#x2122; x 100% đ?&#x2018;&#x2019;đ?&#x2018;Ľđ?&#x2018;Ąđ?&#x2018;&#x2019;đ?&#x2018;&#x;đ?&#x2018;&#x203A;đ?&#x2018;&#x17D;đ?&#x2018;&#x2122;

2.3 =

đ??¸đ?&#x2018;&#x2013;đ?&#x2018;&#x203A;đ?&#x2018;Ąđ?&#x2018;&#x2019;đ?&#x2018;&#x;đ?&#x2018;&#x203A;đ?&#x2018;&#x17D;đ?&#x2018;&#x2122; 20 000

x 100%

Example Very Bright Sunlight Bright Sunlight Clear Sky Overcast day Sunrise / Sunset on clear day Midday Fully overcast Sunset, Storm cloud

=

2.3 đ?&#x2018;Ľ 20000 100

= 460 lux

Conclusion In conclusion, the daylight factor of the cafĂŠ is 2.3% and having a natural illumination of 460 lux.

According to the requirements of MS 1525, having a daylight factor of 2.3% only meets a fair daylight distribution factor but it meet more than enough of natural illumination of a standard cafeteria requirement which is 200 lux. Hence, it might be dark to be in the cafeteria but it has already meet a natural illumination requirement by MS 1525.

2.1.2

Artificial Lighting

According to MS 1525, the recommended illumination level of a cafeteria space is 200 lux.

Type of fixture

Recessed Fluorescent Lamp

Type of light bulb

Material of fixture

Aluminium

Product Brand & Code

EPC 14-1

Wattage Range (W)

26

Colour Temperature, K

3200

Colour Designation

Warm White

Lumens

2750

Dimension of room, L x W (m)

8.65 x 6.57 + (0.85 x 487)/2

Floor Area, A (m2 )

58.7

Height of Ceiling, H (m)

5.6

Lumen (Lux)

520

Height of Luminaire (m)

5.6

Height of Work Level (m)

0.8

Mounting Height (Hm)

4.8

Reflection Factors

Utilisation Factor (UF)

Ceiling: 0.7 Wall: 0.5 Floor: 0.2 8.65 đ?&#x2018;Ľ 6.57 (8.65 + 6.57)đ?&#x2018;Ľ 4.8 = 0.78 0.34

Maintenance Factor (MF)

0.80

Number of Lamps Required

N= 2750 đ?&#x2018;Ľ (0.34 đ?&#x2018;Ľ 0.80)

Room Index/ RI (K)

200 đ?&#x2018;Ľ 58.7

đ?&#x2018;Źđ?&#x2019;&#x2122;đ?&#x2018;¨

N= đ?&#x2018;­ đ?&#x2019;&#x2122; đ?&#x2018;źđ?&#x2018;­ đ?&#x2019;&#x2122; đ?&#x2018;´đ?&#x2018;­ Spacing to Height Ratio (SHR)

Fittings Layout

= 15.7 = 16 lamps 1 58.7 SHR = 3 X â&#x2C6;&#x161; 16 = 0.64 đ?&#x2018;&#x2020; SHR= 3 = 0.64 S = 1.92 8.65 Fittings required along 8.65m wall= 1.92 = 4.5 = 5 rows 16 Number of lamps in each row = 5 = 3.2 = 4 lamps 6.54 Spacing along 6.54 wall = 4 = 1.64m

Final Layout

Conclusion From the calculation result, 20 fluorescent lamps are used to illuminate the cafĂŠ area in order to achieve the minimum illuminance of 200 lux stated by MS1525. By providing a sufficient illuminance, users will be able to perform tasks more accurate and efficiently.

2.1.3

Permanent Supplementary Artificial Lighting of Interior (PSALI)

Referring to the daylight factor calculation above, the cafĂŠ has only a fair daylight factor distribution of 2.3%. Due to the fact that very less direct sunlight is being penetrated into the space, artificial lighting are to be used to light up the space. From the artificial calculation results, the usage of 20 lamps is needed to illuminate the space. Hence, PSALI is applied whereby the lightings are to be controlled with two switches. The first switch will control the first two rows facing towards the entrance as there will be more light penetrating in, whereas the second switch will control the last three rows towards the kitchen.

PSALI Fitting Layout

2.1

Childrenâ&#x20AC;&#x2122;s Library 2.2.1

Daylight

According to MS 1525, Daylight Factor Distribution is as below: Zone Very Bright Bright Average Dark

Daylight Factor (%) >6 3-6 1-3 0-1

Distribution Very large with thermal and glare problems Good Fair Poor

The childrenâ&#x20AC;&#x2122;s library is located on the upper ground floor facing the back alley of the building with an open garden right beside it. As the space is facing the south sun, the most of the walls are open outwardly to the garden to allow maximum daylight into the building and at the same time allow user to connect to the greeneries while reading. The use of the garden will also prevent direct glare into the space.

Daylight Factor Calculation Floor Area (đ?&#x2018;&#x161;2 ) Area of faç ade exposed to sunlight (đ?&#x2018;&#x161;2 ) Area of skylight Exposed Faç ade & Skylight Area to Floor Area ratio/ Daylight Factor, DF

44.0 21.71 0 (21.71+0) 44.0

= 0.49 = 49% x 0.1 = 4.9%

Natural Illumination Calculation Illuminance 120,000 lux 110,000 lux 20,000 lux 1000-2000 lux 400 lux <200 lux 40 lux <1 lux

Example Very Bright Sunlight Bright Sunlight Clear Sky Overcast day Sunrise / Sunset on clear day Midday Fully overcast Sunset, Storm cloud

Eexternal = 20 000 lux đ??¸

DF= đ??¸ đ?&#x2018;&#x2013;đ?&#x2018;&#x203A;đ?&#x2018;Ąđ?&#x2018;&#x2019;đ?&#x2018;&#x;đ?&#x2018;&#x203A;đ?&#x2018;&#x17D;đ?&#x2018;&#x2122; x 100% đ?&#x2018;&#x2019;đ?&#x2018;Ľđ?&#x2018;Ąđ?&#x2018;&#x2019;đ?&#x2018;&#x;đ?&#x2018;&#x203A;đ?&#x2018;&#x17D;đ?&#x2018;&#x2122;

4.9 =

=

đ??¸đ?&#x2018;&#x2013;đ?&#x2018;&#x203A;đ?&#x2018;Ąđ?&#x2018;&#x2019;đ?&#x2018;&#x;đ?&#x2018;&#x203A;đ?&#x2018;&#x17D;đ?&#x2018;&#x2122; 20 000

x 100%

4.9 đ?&#x2018;Ľ 20000 100

= 980 lux

Conclusion The childrenâ&#x20AC;&#x2122;s library has a daylight factor of 4.9% and natural illumination of 380 lux. Based on the requirements from MS 1525 from the chart above, the daylight factor of the childrenâ&#x20AC;&#x2122;s library falls between the 3-6% value, which means this space has a good daylight distribution. On the other hand, the illuminace value is higher than the required value of a standard reading are which is 300lux. This would be a problem when it comes to thermal and glare, which might cause discomfort of the users.

In order to solve this problem, low-e glass panels can be used as faç ade to minimize penetration of ultraviolet and infared rays into the space. Besides that, overhangs can also be used to further reduce the direct sunlight from penetrating into the building.

2.2.2

Artificial Lighting

According to MS 1525, the recommended illumination level of a library space is 300-500 lux.

Type of fixture

LED Downlight

Type of light bulb

Material of fixture

Aluminium

Product Brand & Code

DN571B

Nominal life (hours)

25 000

Wattage Range (W)

36

CRI

80

Colour Temperature, K

3000

Colour Designation

Warm White

Lumens

4000

Dimension of room, L x W (m)

6.2 x 7.1m

Floor Area, A (m2 )

44.0

Height of Ceiling, H (m)

3.8

Lumen (Lux)

4000

Height of Luminaire (m)

3.8

Height of Work Level (m)

0.8

Mounting Height (Hm)

3.0

Reflection Factors

Ceiling: 0.7 Wall: 0.5 Floor: 0.2

Utilisation Factor (UF)

6.2 đ?&#x2018;Ľ 7.1 (6.2 + 7.1)đ?&#x2018;Ľ 3.2 = 1.03 0.40

Maintenance Factor (MF)

0.80

Number of Lamps Required

N= 4000 đ?&#x2018;Ľ (0.4 đ?&#x2018;Ľ 0.8)

Room Index/ RI (K)

đ?&#x2018;Źđ?&#x2019;&#x2122;đ?&#x2018;¨

N= đ?&#x2018;­ đ?&#x2019;&#x2122; đ?&#x2018;źđ?&#x2018;­ đ?&#x2019;&#x2122; đ?&#x2018;´đ?&#x2018;­ Spacing to Height Ratio (SHR)

Fittings Layout

300 đ?&#x2018;Ľ 44.0

= 10.31 = 10 1 44.0 SHR = 3 X â&#x2C6;&#x161; 10 = 0.7 đ?&#x2018;&#x2020; SHR= 3 = 0.7 S = 2.1 7.1 Fittings required along 7.1m wall= 2.1 = 3.38 = 3 rows 10 Number of lamps in each row = 3 = 3.3 = 4 lamps 6.2 Spacing along 6.2 wall = 4 = 1.55m

Final Layout

Conclusion In conclusion, in order to achieve the minimum illumincance of 300 lux required by MS 1525, 12 LED downlights are needed to illuminate the childrenâ&#x20AC;&#x2122;s library. With the sufficient illuminance provided, the children are then able to read comfortably in the space.

2.1.3

Permanent Supplementary Artificial Lighting of Interior (PSALI)

As the daylight factor of the childrenâ&#x20AC;&#x2122;s library meets the requirement of MS 1525 where it falls in between the Daylight Factor Distribution of 3-6%, the space has a good daylight factor.

Through the result of the light contour diagram, the space also receives a sufficient amount of sunlight during the day especially the space towards the opening. Besides that, from the artificial lighting calculation result, a total of 12 LED downlights will be needed to illuminate the childrenâ&#x20AC;&#x2122;s library. With all the results and observation, PSALI is applied by controlling the switch of the light fittings. It can be applied by dividing the fittings into 2 switches, the first 2 row nearer to the opening are controlled by one switch and the remaining two rows will be controlled by another switch. Hence, during the day, the two rows of light fittings nearer to the opening can be switch off as it may have sufficient light.

PSALI Fitting Layout

3.0 ACOUSTIC 3.1

External Noise Pressure Level 3.1.1

CafĂŠ

CAFE

KITCHEN

Although the cafĂŠ is located at the front entrance of the building facing Jalan Sultan Azlan Shah, the sound level of the main road is taken as the main external noise sound to calculate the external noise sound pressure level.

Peak Hour Highest reading = 80dB đ??ź

Using the formula, L

=

10log10 ( )

80

=

10log10 (1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 8 = I

=

đ??źđ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

1x 10-4

Lowest reading = 65dB Using the formula, L 65

đ??ź

=

10log10 (đ??ź )

=

10log10 ( 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 6.5 =

đ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

I

=

3.16 x 10-6

Total Intensity, I

=

(1x 10-4) + (3.16x 10-6)

=

1.03 x 10-4 đ?&#x2018;?2

Using the formula, Combined SPL = 10 log10 ( đ?&#x2018;? 2 ), where po = 1 x 10-12 đ?&#x2018;&#x153;

Combined SPL

=

10 log10 (

=

80.13 dB

1.03 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;4 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

Non-Peak Hour Highest reading = 55dB đ??ź

Using the formula, L

=

10log10 (đ??ź )

5.5

=

10log10 (1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 5.5 = I

đ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

=

3.16 x 10-7

=

10log10 (đ??ź )

=

10log10 ( 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

Lowest reading = 50dB Using the formula, L 65

log-1 5.0 =

đ??ź

đ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

)

I

=

1 x 10-7

Total Intensity, I

=

(3.16 x 10-4) + (1 x 10-6)

=

4.16 x 10-4 đ?&#x2018;?2

Using the formula, Combined SPL = 10 log10 ( đ?&#x2018;? 2 ), where po = 1 x 10-12 đ?&#x2018;&#x153;

Combined SPL

=

10 log10 (

=

56.19

4.16 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;7 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

)

Conclusion To sum up, according to the Noise Criteria for acoustic environment in building interiors, the standard reading of a cafĂŠ /restaurant should be within range of NC 40 â&#x20AC;&#x201C; 45 which is 50-55dB. From the calculation above, the combined sound pressure level around the cafĂŠ during peak and non-peak hour are 80.13dB and 56.19dB respectively. This means that during peak hour, the SPL highly exceeds the noise criteria, thus negatively affecting the quality of the space. Whereas during nonpeak hour, the SPL only slightly exceeds the noise criteria, therefore during non-peak hour, it is still a fairly good space for a cafĂŠ . In order to solve this problem, a kitchen space is inserted to separate the cafĂŠ and the main road and work as a buffering zone to reduce defect noise penetrating to the cafĂŠ .

3.1

External Noise Pressure Level 3.1.2

Childrenâ&#x20AC;&#x2122;s Library

CHILDRENâ&#x20AC;?S LIBRARY CAFE

KITCHEN

As the childrenâ&#x20AC;&#x2122;s area is located at the back part of the building, the sound pressure level of the back lane is obtained to be used for the calculation of the external noise pressure level.

Peak Hour Highest reading = 70dB đ??ź

Using the formula, L

=

10log10 ( )

70

=

10log10 (1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 7.0 = I

=

đ??źđ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

1x 10-5

Lowest reading = 50dB Using the formula, L 50

đ??ź

=

10log10 (đ??ź )

=

10log10 ( 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 5.0 =

đ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

I

=

1.0 x 10-7

Total Intensity, I

=

(1x 10-5) + (1.0x 10-7)

=

1.01 x 10-5 đ?&#x2018;?2

Using the formula, Combined SPL = 10 log10 ( đ?&#x2018;? 2 ), where po = 1 x 10-12 đ?&#x2018;&#x153;

Combined SPL

=

10 log10 (

=

70.04dB

1.01 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;5 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

Non-Peak Hour Highest reading = 50dB đ??ź

Using the formula, L

=

10log10 (đ??ź )

5.0

=

10log10 (1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 5.0 = I

=

đ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

1.07 x 10-7

)

Lowest reading = 46dB đ??ź

Using the formula, L

=

10log10 (đ??ź )

4.6

=

10log10 ( 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12 )

log-1 4.6 =

đ?&#x2018;&#x153;

đ??ź

đ??ź 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

I

=

4.0 x 10-8

Total Intensity, I

=

(1.07 x 10-7) + (4.0 x 10-8 )

=

1.47 x 10-7 đ?&#x2018;?2

Using the formula, Combined SPL = 10 log10 ( đ?&#x2018;? 2 ), where po = 1 x 10-12 đ?&#x2018;&#x153;

Combined SPL

=

10 log10 (

=

51.67dB

1.47 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;7 1 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;12

)

Conclusion In conclusion, the combined external SPL during peak and non-peak hours are 70.04dB and 51.67dB. According to the Noise Criteria chart, the range should be of NC 35-40, which is equivalent to 4050dB. Similarly to the space of the cafĂŠ analyzed above, during the peak hour, the reading highly exceeds the standard required however during non-peak hour, it only has a slight difference when compared to the standard recommended noise criteria. Therefore, it would not be comfortable to read during peak hour. As to solve the issue, brick wall is proposed to filter the noise from the back alley.

3.2

Reverberation Time Childrenâ&#x20AC;&#x2122;s Library

Space Volume = =

7.17m x 6.1m x 3.8m 166.2m3

Standard Reverberation Time

=

0.4 â&#x20AC;&#x201C; 0.6 seconds

Material absorption coefficient at 500Hz at non-peak hour with 5 person in the space Building Components Floor Wall

Material

Concrete Concrete Glass Ceiling Plaster Door Glass Furniture Wooden book shelf Cloth-upholstered People Total absorption, A

Absorption Coefficient, a 0.02 0.05 0.10 0.02 0.05 0.1 0.8 0.40/P

Area, S/m3 43.8 47.07 52.46 43.8 4.83 35.2 3.0 5

Sound Absorption, SA 0.88 2.35 5.25 0.88 0.24 3.52 2.4 2.0 17.52

Material absorption coefficient at 500Hz at peak hour with 20 person in the space.

Building Components Floor Wall

Material

Concrete Concrete Glass Ceiling Plaster Door Glass Furniture Wooden book shelf Cloth-upholstered People Total absorption, A

Absorption Coefficient, a 0.02 0.05 0.10 0.02 0.05 0.1 0.8 0.40/P

Area, S/m3 43.8 47.07 52.46 43.8 4.83 35.2 3.0 20

Sound Absorption, SA 0.88 2.35 5.25 0.88 0.24 3.52 2.4 8.0 23.52

500Hz (non-peak hour) Reverberation Time, RT =

= =

0.16 đ?&#x2018;&#x2039; đ?&#x2018;&#x2030; đ??´ 0.16 đ?&#x2018;&#x2039; 166.2 17.52

1.52s

500Hz (peak hour) Reverberation Time, RT =

= =

0.16 đ?&#x2018;&#x2039; đ?&#x2018;&#x2030; đ??´ 0.16 đ?&#x2018;&#x2039; 166.2 23.52

1.13s

Conclusion From the result of the calculation, the reverberation time of the childrenâ&#x20AC;&#x2122;s library at 500Hz during non-peak hour and peak hour are 1.52 seconds and 1.13 seconds respectively. According to the standard reverberation time given which is 0.4 â&#x20AC;&#x201C; 0.6 second, the result far exceeds the given range. This shows that the space is lacked of absorptive materials which will affect the comfort of users while they are in the space. Therefore to encounter the problem, the floor can be covered with carpets while curtains also can be used to cover the windows to reduce the reverberation value.

3.3

Sound Reduction Index

CafĂŠ

Building Element

Material

Door Wall

Glass Concrete Glass

Surface Area (m2) 3.15 58.24 64.51

Glass Door Sound Reduction Index, SRI 26 Log-1 2.6 T

1

=

10log10 ( đ?&#x2018;&#x2021; )

=

10log10 ( đ?&#x2018;&#x2021; )

=

1 đ?&#x2018;&#x2021;

=

2.51 x 10-3

=

10log10 ( đ?&#x2018;&#x2021; )

=

10log10 ( đ?&#x2018;&#x2021; )

đ?&#x2018;&#x17D;đ?&#x2018;Ł

1

đ?&#x2018;&#x17D;đ?&#x2018;Ł

Concrete Wall Sound Reduction Index, SRI 45

1

đ?&#x2018;&#x17D;đ?&#x2018;Ł

1

đ?&#x2018;&#x17D;đ?&#x2018;Ł

SRI (dB) 26 45 26

Transmission Coefficient, T 2.51 x 10-3 3.16 x 10-5 2.51 x 10-3

Log-1 4.5 T

=

1 đ?&#x2018;&#x2021;

=

3.16 x 10-5

=

10log10 ( đ?&#x2018;&#x2021; )

=

10log10 ( đ?&#x2018;&#x2021; )

=

1 đ?&#x2018;&#x2021;

=

2.5 x 10-3

Glass Wall Sound Reduction Index, SRI 26 Log-1 2.6 T

1

đ?&#x2018;&#x17D;đ?&#x2018;Ł

1

đ?&#x2018;&#x17D;đ?&#x2018;Ł

Average Transmission Coefficient of Materials Tav

=

=

(3.15 đ?&#x2018;Ľ 2.51 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;3 )+( 58.24 đ?&#x2018;Ľ 3.16 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;5 ) +(64.21 đ?&#x2018;Ľ 2.51 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;5 ) ( 3.15+ 58.24 + 64.21 ) (7.90 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;3 )+( 1.84 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;3 ) +(1.61 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;3 ) ( 125.6 )

=

9.04 x 10-5

SRI =

10 log10 (đ?&#x2018;&#x2021;)

1

1

=

10 log10 (9.04 đ?&#x2018;Ľ 10â&#x2C6;&#x2019;5 )

=

40.44dB

External Sound Pressure Level =

80dB

Sound Transmitted into Space =

80 â&#x20AC;&#x201C; 40.44

=

39.56dB

Conclusion From the sound reduction index calculation, the average transmission coefficient of the materials of the cafĂŠ is 40.44dB. If given that the sound pressure level from the main road is 80dB, the sound transmitted into the cafĂŠ area is approximately 39.56d. According to the noise criteria environment perception, the recommended range is 50-55dB. Which means that the space has already meet the requirement.

4.0

Reference

1. Department of Standards Malaysia. (2007) Malaysian Standard: Code of Practice on Energy Efficiency and use of Renewable Energy for Non-Residential Buildings (First Revision). Malaysia: Department of Standards Malaysia

2. NC - Noise Criterion. (n.d.). Retrieved July 09, 2016, from http://www.engineeringtoolbox.com/nc-noise-criterion-d_725.html 3. Cowab, J, (2000) Architectural Acoustics, Design Guide, Mc Graw-Hill, N.Y 4. Long,M. (2006), Architectural Acoustics. Amsterdam: Elsevier/ Academic Press