building science 2 project 2

SCHOOL OF ARCHITECTURE, BUILDING &DESIGN

BACHELOR OF SCIENCE (HONOURS) IN ARCHITECTURE

BUILDING SCIENCE 2 (ARC 3413)

PROJECT 2: INTERGRATION PROJECT WITH DESIGN STUDIO 5

SENTUL COMMUNITY LIBRARY

LIGHTING AND ACOUSTIC PROPOSAL REPORT & CALCULATION

LIM YEE QUN 0319121

TUTOR: MR. EDWIN YEAN LIONG CHAN

SUBMISSION DATE: 11TH JULY 2016

TABLE OF CONTENT

CONTENT

1.0 INTRODUCTION

1.1 Objectives

1.2 Project Description

1.3 Floor Plans

2.0 LIGHTING

2.1 Children Reading Area

2.1.1 Daylighting Analysis

2.1.2 Artificial Lighting Proposal

2.1.3 PSALI (Permenant Supplementary Artificial Lighting of Interiors)

2.2 Formal Reading Area

2.2.1 Daylighting Analysis

2.2.2 Artificial Lighting Proposal

2.2.3 PSALI (Permenant Supplementary Artificial Lighting of Interiors)

3.0 ACOUSTIC

3.1 Sound Pressure Level – External Noises

3.1.1 Children Reading Area

3.1.2 Formal Reading Area

3.2 Reverberation Time ( RT)


3.2.2 Meeting Room

3.3 Sound Reduction Index (SRI)


3.3.2 Formal reading Area

4.0 REFERENCES

1.0 INTRODUCTION

1.1 OBJECTIVES

This project aims to integrate the understanding of lighting and acoustic principles in the context of the

Design Studio 5 final design. It enhances the understanding of lighting and acoustics principles and

enables students to solve design problems in relation to sustainability issues (natural lighting, site

analysis). Thus, it encompasses advanced day lighting systems and the integration of electrical lighting,

strategies for noise management and room acoustic.

1.2 PROJECT DESCRIPTION

In studio 5, Students are required to design a community library within an urban infill site. Apart from

developing an appropriate formal and elevational strategy in response to the character of the street, the

design should take into consideration a holistic application of structural, functional and environmental

requirements to address the user needs for a community library.

The new library, which located at Jalan Ipoh, Sentul, will be a vibrant and interesting place for the whole

community, welcoming people of different ages and background. It will be a focus point for variety of

cultural, learning and recreational opportunities. The role of the library is

- An inspiring and inviting library building

- A focal point for the community

- Reader places and computers places to meet growing demand

- A better displayed and housed collection

- Better Facilities for target groups

- A showcase for historical resources of the local government areas

- A small meeting room which can be used for variety of purposes

- A multifunction space for a range of activities including travelling exhibitions, children’s

storytelling and activities, meetings of specialist groups.

1.3 FLOOR PLANS

Figure 1.3.1 Ground Floor Plan

Figure 1.3.2 First Floor Plan

Figure 1.3.3 Second Floor Plan

Figure 1.3.4 Third Floor Plan

Figure 1.3.5 Fourth Floor Plan

2.0 LIGHTING

2.1 CHILDREN’S READING AREA

2.1.1 DAYLIGHTING ANALYSIS

According to MS 1525, Daylight Factor distribution as below:

Daylight Factor, DF

DF,% Distribution

>6 Very bright with thermal & glare problem

3-6 Bright

1-3 Average

0-1 Dark

The selected area, Children’s Reading Area is located at first floor which has a ceiling height of 5m.

Large amount of windows are able to allow natural sunlight penetrate into this area. Hence, artificial

lighting is only required during night time.

Figure 2.1.1.1 First Floor Plan which indicate Children Reading Area.

Daylight Factor Calculation

Floor Area 11.1m X 9.85 m = 105.45 m2

Area of façade that exposed to sunlight 16m X 3.5m = 56m2

Area of sunlight 0

Exposed of façade & skylight area to floor area Ration/ Daylight Factor, DF

(56m2 + 0) /105.45m2 = 0.53 53% X 0.1 = 5.3%

Natural Illumination Calculation

Illuminance Example

120,000 lux Brightest sunlight

110,000 lux Bright sunlight

20,000 lux Shade illuminated by entire clear blue sky

1,000 – 2,000 lux Typical overcast day, midday

< 200 lux Extreme of darkest storm clouds, midday

400 lux Sunrise or sunset on clear day

40 lux Fully overcast, sunset / sunrise

< 1 lux Extreme of darkest storm clouds, sunset / sunrise

E external = 20,000 lux

DF = (E internal / E external) X 100%

5.3% = (E internal / 20,000) X 100%

E internal = 5.3 X 20,000 /100

= 1060 lux

Conclusion

Based on the requirement of MS 1525, the daylight factor should be lower than 6% and the

recommended illumination level for a study area is 400 lux. The children reading area has a daylight

factor of 5.3% which fulfill the standard, but the value of natural illumination of 1060 lux exceed the

standard. This will cause thermal and glare problem. Hence, double glazed low e-value glass is applied

in order to solve the glare problem and also reduce the heat gain in this area.

Double glazed low e-value glass are proposed to minimize the amount of ultraviolet and infrared light

that can pass through without compromising the amount of visible light that is transmitted.

Figure 2.1.1.2 Double Glazed Low E-value Glass.

2.1.2 ARTIFICIAL LIGHTING PROPOSAL

The Children Reading area will be operated not just on the day but night too. Hence, artificial lighting is

vital for the space to produce a well-lit and comfortable reading environment. Based on MS 1525, the

required lux level for a reading area is 300-400.

Type of luminaire proposed:

Type of fixture LED Downlight

Type of light bulb

Material of fixture Aluminium

Product Brand & Code LEDXION K01116

Nominal Life (hours) 50,000

Wattage Range (W) 44

CRI 85

Color Temperature, K 3000

Color Designation Warm White

Lumens 5000

Lumen Method Calculation

Dimension of Room Width : 11.1 m Length : 9.85 m Height : 5 m

Floor Area 11.1 m X 9.85 m =109.34 m

Lumen of lighting fixture F (lux) 5000 Lm

Height of Luminaire (m) 5 m

Mounting height (Hm) 5 m – 0.8 m = 4.2 m

Reflection Factors Ceiling : 0.7 Wall : 0.5 Floor : 0.2

Room index, RI (K)

RI = 𝐿 𝑋 𝑊

𝐻𝑚 𝑋 (𝐿+𝑊)

9.85 𝑋 11.1

4.2 𝑋 (9.85 + 11.1)

= 1.24

Utilization Factor (UF) 0.55

Maintenance Factor (MF) 0.8

Standard Illuminance by MS1525 300

Number of light required

N = 𝐸 𝑋 𝐴

𝐹 𝑋 𝑈𝐹 𝑋 𝑀𝐹

N = 𝐸 𝑋 𝐴


N = 300 𝑋 109.34

5000 𝑋 0.55 𝑋0.8

N = 14.91 N =15

Spacing to Height Ratio SHR = 1

𝐻𝑚 X √

𝐴

𝑁

= 1

4.2 X √

109.34

15

= 0.64

SHR = 𝑆

4.2

0.64 = 𝑆

4.2

S = 0.64 X 4.2 = 2.69 m

Fitting Layout by approximately (m) Fittings required along 11.1 wall = 11.1

2.69

= 4.12 = 4 row

Number of lamps in each row = 15

4

= 3.75 = 4 Therefore 4 X 4 layout is appropriate for the room.

Space along 9.85 wall will be 9.85

4 = 2.46m

Fitting Layout

Figure 2.1.2.1: Proposed Luminaries Fitting Layout of Children Reading Area

Conclusion

16 LED lights are used to illuminate the children reading area to achieve minimum of 300 lux stated by

MS 1525. It is arranged with 4 rows of 4 LED lights. With the sufficient level of illumination, children are

able to read in a well illuminated and comfortable atmosphere.

2.1.3 PSALI (PERMANENT SUPPLEMENTARY ARTIFICIAL LIGHTING OF INTERIORS)

The total 16 luminaires in the children reading area can be controlled by two switches. Each of them

control 8 luminaires. Switch 1 control the first two rows which near the façade while Switch 2 control the

following two rows. During daytimes, the luminaires of first two row can be switch off due to the

sufficient natural lighting. Therefore, electrical cost can be saved.

Figure 2.1.3.1 Proposed Reflected Ceiling Plan and Switch Arrangement

2.2 FORMAL READING AREA

2.2.1 DAYLIGHTING ANALYSIS

According to MS 1525, Daylight Factor distribution as below:

Daylight Factor, DF

DF,% Distribution

>6 Very bright with thermal & glare problem

3-6 Bright

1-3 Average

0-1 Dark

The selected area, Formal Reading Area is located at fourth floor which has a ceiling height of 5.2m.

The glazing area of this space is larger than Children Reading Area which bring richness of natural

sunlight into this area. Therefore, there are no need of artificial lighting in this area.

Figure 2.2.1.1 Fourth Floor Plan which indicates Formal Reading Area.

Daylight Factor Calculation

Floor Area 6.725m X 6.5 m = 43.71 m2

Area of façade that exposed to sunlight 13.225m X 4.4m = 58.19 m2

Area of sunlight 0

Exposed of façade & skylight area to floor area Ration/ Daylight Factor, DF

(58.19m2 + 0) /43.71 m2 = 1.33 133% X 0.1 = 13.3%

Natural Illumination Calculation

Illuminance Example

120,000 lux Brightest sunlight

110,000 lux Bright sunlight

20,000 lux Shade illuminated by entire clear blue sky

1,000 – 2,000 lux Typical overcast day, midday

< 200 lux Extreme of darkest storm clouds, midday

400 lux Sunrise or sunset on clear day

40 lux Fully overcast, sunset / sunrise

< 1 lux Extreme of darkest storm clouds, sunset / sunrise

E external = 20,000 lux

DF = (E internal / E external) X 100%

13.3% = (E internal / 20,000) X 100%

E internal = 13.3 X 20,000 /100

= 2660 lux

Conclusion

The Formal Reading Area has a daylight factor of 13.3% and natural illumination off 2660 lux. Based on

the requirement of MS 1525, the daylight factor should be lower than 6% and the recommended

illumination level for a study area is 400 lux. Both of the values of this space exceed the standards. This

will cause thermal and glare problem. Hence, adjustable shading device is applied to solve the glare

problem and also reduce the heat gain in this area.

The wooden brise-soleil panel structure guarantees protection of the complex. It is adjustable extruded

wooden blade shutters with aluminum profile frame. The movable and adjustable blades can be

adjusted to the required position manually. Angled blades optimize the shading provided depending on

the local conditions and the design of the building.

Figure 2.2.1.2 Wooden Brise-Soleil Panel Structure.

2.2.2 ARTIFICIAL LIGHTING PROPOSAL

The Formal Reading Area is well-lit at daytimes. Hence, artificial lighting is only used at night time or

cloudy day to produce a well-lit and comfortable reading environment.

Type of luminaire proposed:

Type of fixture Fluorescent tube with reflector

Type of light bulb

Material of fixture Aluminium

Product Brand & Code F39W/TS/830/ECO

Nominal Life (hours) 36,000

Wattage Range (W) 39

CRI 85

Color Temperature, K 3000

Color Designation Warm White

Lumens 3500

Lumen Method Calculation

Dimension of Room Width : 6.725 m Length : 6.5 m Height : 5.2 m

Floor Area 6.725 m X 6.5 m =43.71 m

Lumen of lighting fixture F (lux) 3500 Lm

Height of Luminaire (m) 5.2 m

Mounting height (Hm) 5.2 m – 0.8 m = 4.4 m

Reflection Factors Ceiling : 0.7 Wall : 0.5 Floor : 0.2

Room index, RI (K)

RI = 𝐿 𝑋 𝑊

𝐻𝑚 𝑋 (𝐿+𝑊)

6.725 𝑋 6.5

4.4 𝑋 (6.725 + 6.5)

= 0.75

Utilization Factor (UF) 0.34

Maintenance Factor (MF) 0.8

Standard Illuminance by MS1525 300

Number of light required

N = 𝐸 𝑋 𝐴


N = 𝐸 𝑋 𝐴


N = 300 𝑋 43.71

3500 𝑋 0.34 𝑋0.8

N = 13.77 N =14

Spacing to Height Ratio SHR = 1

𝐻𝑚 X √

𝐴

𝑁

= 1

4.4 X √

43.71

14

= 0.4

SHR = 𝑆

4.4

0.4 = 𝑆

4.4

S = 0.4 X 4.4 = 1.76 m

Fitting Layout by approximately (m) Fittings required along 6.725 wall = 6.725

1.76

= 3.82 = 4 row

Number of lamps in each row = 14

4

= 3.5 = 4 Therefore 4 X 4 layout is appropriate for the room.

Space along 6.5 wall will be 6.5

4 = 1.625m

Fitting Layout

Figure 2.2.2.1: Proposed Luminaries Fitting Layout of Formal Reading Area

Conclusion

In the end, the formal reading area is arranged with 4 rows of 4 fluorescent luminaire with reflector.

Although this space is smaller than the children reading area, the number of luminaires is same. It is

because the mounting height of this space is greater but the lumen of luminaires are smaller. The

spacing between each luminaires is smaller to achieve the requirement of minimum 300 lux in the room

as stated in the room.

2.2.3 PSALI (PERMANENT SUPPLEMENTARY ARTIFICIAL LIGHTING OF INTERIORS)

The total 16 luminaires in the formal reading area can be controlled by two switches. Each of them

control 8 luminaires. During daytimes, the luminaires can be switch off as there is enough sufficient

natural lighting. Due to the sun orientation, the users can gradually switch on the light in the evening to

minimize the usage of electricity.

Figure 2.2.3.1 Proposed Reflected Ceiling Plan and Switch Arrangement

3.0 ACOUSTIC

3.1 EXTERNAL NOISE SOUND PRESSURE

3.1.1 CHILDREN READING AREA

The Children Reading Area on the first floor is selected as a space to analyze and compare the

external noise sound pressure level at Jalan Ipoh. Readings are collected at both peak hours and non-

peak hours.

Figure 3.1.1.1 First Floor Plan that indicates Children Reading Area and Jalan Ipoh

Peak Hour

Highest Reading = 75 dB Using the formula,

SIL = 10 log10 𝐼

𝐼𝑎

75 = 10 log10 𝐼

1 𝑋 10−12

107.5 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 7.5

I = 1 X 10 -4.5

Lowest Reading = 62dB Using the formula,

SIL = 10 log10 𝐼

𝐼𝑎

62 = 10 log10 𝐼

1 𝑋 10−12

106.2 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 6.2

I = 1 X 10 -5.8

Total Intensity, I = (1 X 10 -4.5) + (1 X 10 -5.8) = 3.32 X 10 -5

Using the formula, Combined SPL = 10 log10 𝑝2

𝑝02 , where po = 1 X 10 -12

Combined SPL = 10 log10 3.32 𝑋 10−5

1 𝑋 10−12

= 75.21 dB

Non-peak Hour


SIL = 10 log10 𝐼

𝐼𝑎

65 = 10 log10 𝐼

1 𝑋 10−12

106.5 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 6.5

I = 1 X 10 -5.5


SIL = 10 log10 𝐼

𝐼𝑎

54 = 10 log10 𝐼

1 𝑋 10−12

105.4 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 5.4

I = 1 X 10 -6.6



𝑝02 , where po = 1 X 10 -12


1 𝑋 10−12

= 65.33 dB

Conclusion

As a result, the combined sound pressure level of Jalan Ipoh during peak hours and non-peak hours

are 75.21 and 65.33 respectively. The noise criteria for reading space is within the range of NC 35-40.

The noise from the main road will affect the library interiors badly. Users are not able to concentrate

and read in this space. Materials with lower absorption coefficient such as concrete and brick can be

applied to reduce the transmission of noise from the exterior to the interior. Besides this, the green

buffer zone in front the building is also efficient to filter the noise.

3.1.2 FORMAL READING AREA

The Formal Reading Area on the fourth floor is selected as a space to analyze and compare the

external noise sound pressure level at back lane. Readings are collected at both peak hours and non-

peak hours.

Figure 3.1.2 Fourth Floor Plan that indicates Formal Reading Area and Back Lane.

Peak Hour


SIL = 10 log10 𝐼

𝐼𝑎

60 = 10 log10 𝐼

1 𝑋 10−12

106.0 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 6.0

I = 1 X 10 -6.0


SIL = 10 log10 𝐼

𝐼𝑎

52 = 10 log10 𝐼

1 𝑋 10−12

105.2 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 5.2

I = 1 X 10 -6.8



𝑝02 , where po = 1 X 10 -12


1 𝑋 10−12

= 60.64 dB

Non-peak Hour


SIL = 10 log10 𝐼

𝐼𝑎

43 = 10 log10 𝐼

1 𝑋 10−12

104.3 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 4.3

I = 1 X 10 -7.7


SIL = 10 log10 𝐼

𝐼𝑎

38 = 10 log10 𝐼

1 𝑋 10−12

103.8 = 𝐼

1 𝑋 10−12

I = 1 X 10 -12 X 10 3.8

I = 1 X 10 -8.2



𝑝02 , where po = 1 X 10 -12


1 𝑋 10−12

= 44.19 dB

Conclusion

As a result, the combined sound pressure level of back lane during peak hours and non-peak hours are

60.64 and 44.19 respectively. The noise criteria for reading space is within the range of NC 35-40. The

noise from the back lane has lesser impact compare with the main road. The noise from the back lane

during non-peak hours mostly approach to the noise criteria for reading area. Double skin facade can

be applied to filter and deflect noise.

3.2 REVERBERATION TIME


Figure 3.2.1.1 First Floor Plan that indicates Children Reading Area

Standard Reverberation Time (Multipurpose, <750m3) = 1.0 s

Space Volume = Length X Width X Height

= 11.1m X 9.85m X 5m

= 546.675m3

Material Coefficient (500 Hz)

Component Material Absorption Coefficient

Surface Area (m2) / Quantity

Sound Absorption

Floor Carpet 0.14 72 10.08

Laminated Wood Flooring 0.03 79.25 2.38

Wall Concrete with Plaster Finish 0.05 136.175 6.81

Glass 0.10 75.625 7.56

Ceiling Plaster Finish 0.015 109.335 1.64

Door Glass 0.10 5.6 0.56

Furniture Sofa 0.73 34.5 25.185

Laminated Wooden book shelves

0.07 69.2 4.84

People 0.46 20 9.2

Total Absorption (A) 68.255

Reverberation Time, RT = 0.16 𝑋 𝑉

𝐴

= 0.16 𝑋 546.675

68.255

= 1.28s




Sound Absorption


Laminated Wood Flooring 0.05 79.25 3.96

Wall Concrete with Plaster Finish 0.09 136.175 12.26

Glass 0.05 75.625 3.78

Ceiling Plaster Finish 0.02 109.335 2.19

Door Glass 0.05 5.6 0.28

Furniture Sofa 0.89 34.5 30.71

Laminated Wooden book shelves

0.09 69.2 6.23

People 0.51 20 10.2



𝐴

= 0.16 𝑋 546.675

91.21

= 0.96s

Conclusion

The reverberation time for the Children Reading Area at 500Hz and 2000Hz are 1.28s and 0.96s. The

standard of the comfort reverberation time for a multipurpose space within 750m3 is 1 second. This

does not fall within the comfort reverberation at 2000Hz while it is slightly higher than the comfort

reverberation at 500Hz. The design of double ceiling can be applied to reduce the Reverberation time

by using suspended plasterboard as sound absorber.

3.2.2 MEETING ROOM

Figure 3.2.2.1 Second Floor Plan that indicates Meeting Room

Standard Reverberation Time (Speech, <750m3) = 0.75

Space Volume = Length X Width X Height

= 3.5m X 4m X 4m

= 56m3




Sound Absorption


Wall Concrete with Plaster Finish 0.05 60 3

Ceiling Plaster Finish 0.015 14 0.21

Door Glass 0.10 5.6 0.56

Furniture Plastic Seats 0.10 7.644 0.76

Laminated Wooden Table 0.07 6.3 0.44

People 0.46 6 2.76



𝐴

= 0.16 𝑋 56

9.69

= 0.92s




Sound Absorption


Wall Concrete with Plaster Finish 0.09 60 5.4

Ceiling Plaster Finish 0.02 14 0.28

Door Glass 0.05 5.6 0.28

Furniture Plastic Seats 0.15 7.644 1.15

Laminated Wooden Table 0.09 6.3 0.57

People 0.51 6 3.06



𝐴

= 0.16 𝑋 56

14.94

= 0.60s

Conclusion

The reverberation time for the Meeting Room at 500Hz and 2000Hz are 0.92s and 0.60s. The standard

of the comfort reverberation time for a meeting room within 750m3 is 0.75 second. This does not fall

within the comfort reverberation at 2000Hz while it is slightly higher than the comfort reverberation at

500Hz.

3.3 SOUND REDUCTION INDEX (SRI)


Figure 3.3.1.1 First Floor Plan that indicates Children Reading Area

Components Material Area (m2) Sound Reduction Index Transmission Coeffeicient, T

Wall Brick 16.65 45 dB 3.16 X 10 -5

Glass 38.85 26 dB 2.51 X 10 -3

Calculation of transmission coefficient

Sound Reduction Index, SRI = 10 log10 1

𝑇𝑎𝑣

Brick Glass

SRI = 10 log10 1

𝑇

45 = 10 log10 1

𝑇

10 4.5 = 1

𝑇

T = 3.16 X 10-5

SRI = 10 log10 1

𝑇

26 = 10 log10 1

𝑇

10 2.6 = 1

𝑇

T = 2.51 X 10-3

Average Transmission Coefficient of Materials

Tav = (16.65 𝑋 3.16 𝑋 10−5)+( 38.85 𝑋 2.51 𝑋 10−3)

(16.65+38.85)

= 1.77 X 10 -3

SRI = 10 log10 1

𝑇𝑎𝑣

=10 log10 1

1.77 𝑋 10−3

= 27.52 dB

Noise level in Children Reading Area = External Sound Pressure Level (Main Road) – SRI

= 75.21dB – 27.52dB

= 47.69

Conclusion

The sound reduction index of the façade is 27.52dB. After transmission loss, the sound level

of the children reading area is 47.69dB. The value is slightly higher than the desired noise

criteria for a reading space of 35-40dB. Enhancement can be mad by installing double skin

on the facade or absorption panels on the ceiling or walls to reduce noise.

3.3.2 FORMAL READING AREA

Figure 3.3.1.1 Fourth Floor Plan that indicates Formal Reading Area

Components Material Area (m2) Sound Reduction Index Transmission Coeffeicient, T

Wall Brick 14.175 45 dB 3.16 X 10 -5

Glass 20.925 26 dB 2.51 X 10 -3

Wooden Brise-Soleil

20.925 31 dB

Calculation of transmission coefficient

Sound Reduction Index, SRI = 10 log10 1

𝑇𝑎𝑣

Brick Glass Wooden Brise-Soleil

SRI = 10 log10 1

𝑇

45 = 10 log10 1

𝑇

10 4.5 = 1

𝑇

T = 3.16 X 10-5

SRI = 10 log10 1

𝑇

26 = 10 log10 1

𝑇

10 2.6 = 1

𝑇

T = 2.51 X 10-3

SRI = 10 log10 1

𝑇

31 = 10 log10 1

𝑇

10 3.1 = 1

𝑇

T = 7.94 X 10-4

Average Transmission Coefficient of Materials

Tav = (14.175 𝑋 3.16 𝑋 10−5)+( 20.925 𝑋 2.51 𝑋 10−3)+( 20.925 𝑋 7.94 𝑋 10−4)

(14.175+20.925+20.925)

= 1.24X 10 -3

SRI = 10 log10 1

𝑇𝑎𝑣

=10 log10 1

1.24 𝑋 10−3

= 29.07 dB

Noise level in Children Reading Area = External Sound Pressure Level (Main Road) – SRI

= 60.64dB – 29.07dB

= 31.57

Conclusion

The sound reduction index of the façade is 31.57dB. After transmission loss, the sound level

of the formal reading area is 31.57dB. According to MS 1525, the standard Sound Pressure

Level for reading area is 35-40dB, thus the space meets the requirements.

4.0 REFERENCES

Architects’ Data. (2012). Chicester: John Wiley and Sons.

ASHRAE. (1995). ASHRAE handbook 1984 systems. Atlanta, GA: American Society Heating,

Refrigerating &.

In Gibbs, B., In Goodchild, J., In Hopkins, C., & In Oldham, D. (2010). Collected Papers in Building

Acoustics: Room Acoustics and Environmental Noise. Brentwood, Essex: Multi-Science Publishing Co.

Ltd.

Malaysia. (2007). Code of practice on energy efficiency and use of renewable energy for non-

residential buildings (first revision). Putrajaya: Department of Standard Malaysia.

Sound Absorption Coefficients of architectural acoustical materials. (1957). New York.