BUILDING SCIENCE 2 (ARC 3413)
PROJECT 2 INTEGRATION WITH DESIGN STUDIO 5 FINAL REPORT & CALCULATION
Name : LIM JIAN JUN Student ID: 0316867 TUTOR: MR SANJAY
Content Page 1.0 Introduction 1.1 Objectives 1.2 Project Description 2.0 Lighting 2.1 Day Lighting Factor Analysis 2.1.1 Library Integrated Ramp Area 2.1.2 Open CafĂŠ Area 2.2 Artificial Lighting Analysis 2.2.1 Discussion Cubicle 2.2.2 Multi-Purpose Space 3.0 Acoustics 3.1 External Noise Calculation 3.2 Internal Noise Calculation 3.3 Archive Room 3.4 Quiet Study Area 4.0 Reference
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1 INTRODUCTION 1.1 OBJECTIVES This project aims to integrate the understanding of the principles of lighting and acoustics in the context of the final design project of studio 5. It encompasses advanced day lighting systems and the integration of electrical lighting, strategies for noise management and room acoustics.
1.2 PROJECT DESCRIPTION The design project, a Community Library, is a contemporary library space where it sits in an urban infill site at Jalan Sultan Abdul Samad, the heart of Brickfield. Bricks as the major building component not only improves the internal climate of the market, it also helps with the acoustic conditions within. With the insertion of plants in the building, it enhances and amplifies the harmonious community, promoting a healthy and dynamic lifestyle.
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2. LIGHTING 2.1 Daylighting According to MS 1525, Daylight Factor Distribution is as below: Zone Very Bright Bright Average Dark
DF (%) >6 3–6 1–3 0–1
Distribution Very large with thermal and glare problems Good Fair Poor
During the day all artificial lights can be switched off as sun provides natural lighting at major spaces. Artificial lights were only required after in certain spaces such as the book café (for reading) and office (for paperwork).
Figure 2.1 Rendering of Interior Spaces of Library (Daylighting).
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2.1.1
Market Place The market place is located at Ground Floor opening up to the existing back alley and openly design to accommodate market stalls, landscapes and sitting areas. The space has cantilever levels acting as shelter for the users. Light is allowed to light up the market place all day round and no artificial light is needed to lit up the space in the daytime.
Figure 2.2 Open Market Area , Ground Floor
Calculation of Daylight Factor đ??ˇđ??š = Area of Cafe, (m2) Area Exposed to Sunlight, (m2) Daylight Factor (%)
đ??¸đ?‘– Ă— 100% đ??¸đ?‘œ (22 x 6) + (5x4) + 8 = 160 22 x 8 =176 (176 / 160 ) x 0.1 = 11%
According to Table of Natural Illumination, a clear blue sky has a illuminance of 20 000 lux, shade illuminated by entire clear blue sky and midday. ILLUMINANCE 120, 000 lux 110, 000 lux 20, 000 lux
EXAMPLE BRIGHTEST SUNLIGHT BRIGHT SUNLIGHT SHADE ILLUMINATED BY ENTIRE CLEAR BLUE SKY, MIDDAY
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1, 000 â&#x20AC;&#x201C; 2, 000 lux <200 lux 400 lux 40 lux <1 lux
TYPICAL OVERCAST DAY, MIDDAY EXTREME OF DARKEST STORM CLOUDS, MIDDAY SUNRISE OR SUNSET ON A CLEAR DAY (AMBIENT ILLUMINATION) FULLY OVERCAST, SUNSET/SUNRISE EXTREME OF DARKEST STORM CLOUDS, SUNSET/RISE
Given, đ??¸đ?&#x2018;&#x153; (unobstructed sky of Malaysia) 20000 lux Calculation of đ??¸đ?&#x2018;&#x2013; =
đ??ˇĂ&#x2014;đ??¸đ?&#x2018;&#x153; 100 %
11 Ă&#x2014; 20000 = đ?&#x;?đ?&#x;?đ?&#x;&#x17D;đ?&#x;&#x17D; đ?&#x2019;?đ?&#x2019;&#x2013;đ?&#x2019;&#x2122; 100 %
Diagram 2.3 Daylight Analysis Diagram retrieved from ECOTECT.
The Market place is fully exposed to open air and light can easily penetrate through spaces. By cantilever out the building slab above, it allows to provide shelter to the market place while opening up to the context of the site. Double-glazed low e glass and brick wall skin can helps to reduce the irritation from glares.
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2.1.2
Interactive Lounge Interactive lounge is lit up with natural lighting design due to its transparent facade open to the street scape and green wall feature, and also skylight opening at the roof top. The lounge becomes a bright, interactive social space for the community.
Figure 2.4 Interactive Lounge , First Floor
Calculation of Daylight Factor đ??ˇđ??š =
đ??¸đ?&#x2018;&#x2013; Ă&#x2014; 100% đ??¸đ?&#x2018;&#x153;
Area of Lounge, (m2) Window Area Exposed to Sunlight, (m2) Daylight Factor (%)
(10.6 x 8) + (5.8x3)= 102.2 ( 8 + 10.3 )x 4 = 73.2 (73.2 / 102.2 ) x 0.1 = 7.1%
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According to Table of Natural Illumination, a clear blue sky has a illuminance of 20 000 lux, shade illuminated by entire clear blue sky and midday.
Given, đ??¸đ?&#x2018;&#x153; (unobstructed sky of Malaysia) 20000 lux Calculation of đ??¸đ?&#x2018;&#x2013; =
đ??ˇĂ&#x2014;đ??¸đ?&#x2018;&#x153; 100 %
7.1 Ă&#x2014; 20000 = 1420 đ?&#x2018;&#x2122;đ?&#x2018;˘đ?&#x2018;Ľ 100 %
Figure 2.5 Daylight Analysis Diagram retrieved from ECOTECT
According to MS1525, average daylight factor of 5% gives the impression of generous day lighting. However, the courtyard dining area with the daylight factor of 7.1% a lux of 1420 had the potential to cause thermal and glare problems. Thus, proper shading is recommended to avoid thermal and glare problem. By cantilever out the building slab above, it allows to provide shelter to the market place while opening up to the context of the site. Double-glazed low e glass and brick wall skin can helps to reduce the irritation from glares. From the inside, adjustable blinds can be added to tackle excessive glares.
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2.2 Artificial Lighting 2.2.1 Courtyard CafĂŠ The CafĂŠ compromised of both interior and exterior spaces of the cafĂŠ which runs from day to night. Natural Lighting can be acquired outdoor but it is necessarily to install artificial lighting to lit up the space for good dining and socializing environment during night. Material
Function
Color
Surface type
Brick Wall Concrete cement finish Glass
Wall Floor, Ceiling Panels/ Window Seating
Clay red Light grey
Absorptive reflective
Reflectance Value 50 15-50
Transparent
Reflective
6-10
Brown
Absorptive
30
Timber Deck
Lumen Method Formula:
Dimension of room/ L x W, (m) Total Floor Area, (m2) Activity Standard Illuminance Required (lux) According to MS1525 Type of Light
9.4m x 7.8m 73.3 Dining, Eateries 200-300
Led Downlight Watt: 44 Warm White, 2700K Lumen of lighting fixtures / F, (lux) Height of luminaire, (m) Work Level, (m) Mounting height / H, (m) Assumption of reflectance value
Room Index / RI (K) đ?&#x2018;˛=
đ?&#x2018;łĂ&#x2014;đ?&#x2018;ž (đ?&#x2018;ł + đ?&#x2018;ž)đ?&#x2019;&#x2030;đ?&#x2019;&#x17D;
Utilization Factor / UF Maintenance Factor / MF
2700lm 4 0.8 + 0.5 2.7 Ceiling = 0.5, Wall = 0.5, Floor = 0.2 73.3 = 1.58 (17.2)2.7
0.49 0.8 11
Lumen Calculation, N đ?&#x2018;ľ=
đ?&#x2018;ŹĂ&#x2014;đ?&#x2018;¨ đ?&#x2018; Ă&#x2014; đ?&#x2018;źđ?&#x2018; Ă&#x2014; đ?&#x2018;´đ?&#x2018;
300 Ă&#x2014; 9.4 Ă&#x2014; 7.8 = 20.78 đ?&#x2018;?đ?&#x2018;˘đ?&#x2018;&#x2122;đ?&#x2018;?đ?&#x2018; 2700 Ă&#x2014; 0.49 Ă&#x2014; 0.8
Ě´21 Bulbs
SHR RATIO 1 :1= x : Hm x= 2.7
1:1. Reason : Small Space Number of Rows, đ?&#x2018;ľ=
đ?&#x2018;žđ?&#x2019;&#x160;đ?&#x2019;&#x2026;đ?&#x2019;&#x2022;đ?&#x2019;&#x2030; đ?&#x2018;şđ?&#x2019;&#x2018;đ?&#x2019;&#x201A;đ?&#x2019;&#x201E;đ?&#x2019;&#x160;đ?&#x2019;?đ?&#x2019;&#x2C6;
Number of Lamps in a row,
7.8 4.05 = 2.9 rows of lamp Ě´3 rows đ?&#x2018; =
Longitunal Spacing Of Lamp Units
đ?&#x;?đ?&#x;? đ?&#x;&#x2018; = đ?&#x;&#x2022; đ?&#x2019;?đ?&#x2019;&#x201A;đ?&#x2019;&#x17D;đ?&#x2019;&#x2018;đ?&#x2019;&#x201D;
đ?&#x2018;ľ=
đ?&#x2018;&#x2018;=
9.4 7 = 1.34 đ?&#x2018;&#x161;
Figure 2.6 Artificial Light layout 3 x 7 at cafĂŠ area.
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Figure 2.7 Artificial Lighting Analysis Diagram retrieved from ECOTECT.
Above rendering shows illuminance of artificial light ranging 240-300 lux for the cafĂŠ area, which falls within the MS1525 requirement of 200-300 lux for cafĂŠ. 21 lamps are needed and arranged in 3 rows to provide a uniform distribution of illuminance.
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2.2.2
Multipurpose Hall
Multipurpose Studio suggests varies activities to be held in the space by community. There are foldable panels to divide the space and merges the spaces as 1. According to MS1525, the minimum lighting required for a multipurpose room is 500 lux.
Figure 2.8 Multipurpose Studio at Third Floor.
Material
Function
Color
Surface type
Gypsum Board Fabric Gypsum Timber Glass
Ceiling
White
Reflective
Reflectance Value 50
Partition Wall Floor Panels/ Window Seating
Light gray
Absorptive
30-35
Light grey Transparent
Absoptive Reflective
30 6-10
Brown
Absorptive
35
Chair Fabric
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Lumen Method Calculation Dimension of room/ L x W, (m) Total Floor Area, (m2) Activity Standard Illuminance Required (lux) According to MS1525 Type of Light
Lumen of lighting fixtures / F, (lux) Height of luminaire, (m) Work Level, (m) Mounting height / H, (m) Assumption of reflectance value
Room Index / RI (K) đ?&#x2018;˛=
đ?&#x2018;łĂ&#x2014;đ?&#x2018;ž (đ?&#x2018;ł + đ?&#x2018;ž)đ?&#x2019;&#x2030;đ?&#x2019;&#x17D;
Utilization Factor / UF Maintenance Factor / MF Lumen Calculation, N đ?&#x2018;ľ=
đ?&#x2018;ŹĂ&#x2014;đ?&#x2018;¨ đ?&#x2018; Ă&#x2014; đ?&#x2018;źđ?&#x2018; Ă&#x2014; đ?&#x2018;´đ?&#x2018;
16m x 6m 96m2 Multi-functional 500 Recessed track light with GUIO LED (4 luminaries in one track) Watt: 8 Cool White 4X1200 4.0 0.8 (hanging height 0.5) 2.7 Gypsum Ceiling = 0.5, Wall = 0.5, Timber Floor = 0.3 96 = đ?&#x;?. đ?&#x;&#x201D;đ?&#x;? (22)2.7
0.40 0.8 500 Ă&#x2014; 16 Ă&#x2014; 6 = 31.25 đ?&#x2018;?đ?&#x2018;˘đ?&#x2018;&#x2122;đ?&#x2018;?đ?&#x2018; 4 Ă&#x2014; 1200 Ă&#x2014; 0.4 Ă&#x2014; 0.8 = 32 bulbs
Spacing to SHR RATIO 3:2 = x : Hm 3/2 = x/2.7x = 4.05m as spacing Number of Rows, đ?&#x2018;ľ=
đ?&#x2018;žđ?&#x2019;&#x160;đ?&#x2019;&#x2026;đ?&#x2019;&#x2022;đ?&#x2019;&#x2030; đ?&#x2018;şđ?&#x2019;&#x2018;đ?&#x2019;&#x201A;đ?&#x2019;&#x201E;đ?&#x2019;&#x160;đ?&#x2019;?đ?&#x2019;&#x2C6;
16 4.05 = 3.95 rows of lamp đ?&#x2018; =
= 4 rows Number of Lamps in a row,
Longitunal Spacing Of Lamp Units
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đ?&#x2018;ľ=
đ?&#x;&#x2018;đ?&#x;? đ?&#x;&#x2019;
đ?&#x2018;&#x2018;=
= đ?&#x;&#x2013; đ?&#x2019;?đ?&#x2019;&#x201A;đ?&#x2019;&#x17D;đ?&#x2019;&#x2018;đ?&#x2019;&#x201D;
6 8 = 0.75đ?&#x2018;&#x161;
Figure 2.9 Artificial Light layout 4x8 at studio.
Figure 2.10 Artificial lighting Analysis Diagram retrieved from ECOTECT.
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PSALI â&#x20AC;&#x201C;Permanent Supplementary Artificial Lighting Interiots 1.2.1 Self Study Area: The space selected for artificial lighting calculation is the Self-study area with units of study desks. As lighting is important studying and productivity, thus it is needed to keep the space lit up with proper illuminance all the time to promote a suitable study area. According to MS 1525, the space for good reading illuminance is 400 lux.
Area of Self Study Area, (m2) Window Area Exposed to Sunlight, (m2) Daylight Factor (%)
84.2 12 x 4 = 48 (48/ 84.2 ) x 0.1 = 5.7%
Material
Function
Color
Surface type
Gypsum Board Brick Wall Carpeted Flooring Glass
Ceiling
White
Reflective
Reflectance Value 50
Wall Floor
Clay red Light grey
Absorptive Absorptive
50 20
Panels/ Window Seating
Transparent
Reflective
6-10
Brown
Absorptive
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Chair Fabric Lumen Method Formula:
Dimension of room/ L x W, (m) Total Floor Area, (m2) Activity Standard Illuminance Required (lux) According to MS1525 Type of Light
Lumen of lighting fixtures / F, (lux) Height of luminaire, (m) Work Level, (m) Mounting height / H, (m) Assumption of reflectance value
10.8m x 7.8m 84.2m2 Reading, Revision 400 Reflective Fluorescent Grid (2 luminaries in one grid)) Watt: 2700K Cool White 2X1600 4.0 0.8 (hanging height 0.5) 2.7 Ceiling = 0.5, 17
Wall = 0.5, Floor = 0.2 Room Index / RI (K) đ?&#x2018;˛=
84.2 = 1.68 (18.6)2.7
đ?&#x2018;łĂ&#x2014;đ?&#x2018;ž (đ?&#x2018;ł + đ?&#x2018;ž)đ?&#x2019;&#x2030;đ?&#x2019;&#x17D;
Utilization Factor / UF Maintenance Factor / MF Lumen Calculation, N đ?&#x2018;ľ=
đ?&#x2018;ŹĂ&#x2014;đ?&#x2018;¨ đ?&#x2018; Ă&#x2014; đ?&#x2018;źđ?&#x2018; Ă&#x2014; đ?&#x2018;´đ?&#x2018;
0.49 0.8 400 Ă&#x2014; 9 Ă&#x2014; 11 = 27 đ?&#x2018;?đ?&#x2018;˘đ?&#x2018;&#x2122;đ?&#x2018;?đ?&#x2018; 2 Ă&#x2014; 1700 Ă&#x2014; 0.49 Ă&#x2014; 0.8
SHR RATIO 3:2 = x : Hm 3/2 = x/2.7x = 4.05m as spacing Number of Rows, đ?&#x2018;žđ?&#x2019;&#x160;đ?&#x2019;&#x2026;đ?&#x2019;&#x2022;đ?&#x2019;&#x2030; đ?&#x2018;ľ= đ?&#x2018;şđ?&#x2019;&#x2018;đ?&#x2019;&#x201A;đ?&#x2019;&#x201E;đ?&#x2019;&#x160;đ?&#x2019;?đ?&#x2019;&#x2C6; Number of Lamps in a row, đ?&#x;?đ?&#x;&#x2022; đ?&#x;&#x2018; = đ?&#x;&#x2014; đ?&#x2019;?đ?&#x2019;&#x201A;đ?&#x2019;&#x17D;đ?&#x2019;&#x2018;đ?&#x2019;&#x201D;
đ?&#x2018;ľ=
10.5 4.05 = 2.6 rows of lamp đ?&#x2018; =
Longitunal Spacing Of Lamp Units đ?&#x2018;&#x2018;=
7.8 9 = 0.86đ?&#x2018;&#x161;
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Figure 2.11 Artificial layout 3 x 9 at Self Study Corner.
Figure 2.12 Section diagram showing PSALI.
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3. Acoustic 3.1 External Noise Source The project site located next to the intersect junction of Jalan Tun Sambanthan 4 and Jalan Sultan Abdul Samad. It is mainly affected by 2 noise sources: Vehicular paths and Back Alley market. The site is more active in the day due to the markets and also the activities around the site, such as the schools and tradings. The back alley is more quiet at night as the stalls are closed.
Figure 3 Section showing noise sources at site context.
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3.1.1 Calculation Of External Noise : CAFÉ
Figure 3.1 external noise study at Café]
A) BUSY TRAFFIC NOISE
= 70 dB 70
= 10log (l1 / l0)
Antilog 7
= [l1 / (1.0 x 10-12)]
1 x 107
= [l1 / (1.0 x 10-12)]
l1
B) PUBLIC SPACE
= 1.0 x 10-5
= 65 dB 65
= 10log (l1 / l0)
Antilog 6.5
= [l1 / (1.0 x 10-12)]
3.16 x 106
= [l1 / (1.0 x 10-12)]
l1
= 3.16 x 10-6
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= (1.0 x 10-5) + (3.16 x 10-6)
TOTAL INTENSITIES, l
= 1.32 x 10-5
COMBINED SPL
= 10log (l1 / l0) = 10log [(1.32 x 10-5) / (1.0 x 10-12)] = 71 dB
The external noise with a combined SPL of 71dB generated from the vehicles and street activity travels into the Cafe area. According to ANSI the acceptable noise level is a 45-50db. Hence, the cafe area is proposed with exterior skin such as acoustical brick walls, noise filter partition wall (fabric) and some plantation to filter noise.
3.1.2 Calculation of External Noise : Children Library
Figure 3.2 external noise study at Children Library
NOISE SOURCE: A) BACK ALLEY (WET MARKET) = 60 dB 60 Antilog 6
= 10log (l1 / l0) = [l1 / (1.0 x 10-12)] 22
1 x 106 l1
B) PUBLIC SPACE
= [l1 / (1.0 x 10-12)] = 1.0 x 10-6
= 65 dB 65
= 10log (l1 / l0)
Antilog 6.5
= [l1 / (1.0 x 10-12)]
3.16 x 106
= [l1 / (1.0 x 10-12)]
l1
TOTAL INTENSITIES, l
= 3.16 x 10-6
= (1.0 x 10-6) + (3.16 x 10-6) = 4.16 x 10-6
COMBINED SPL
= 10log (l1 / l0) = 10log [(4.16 x 10-6) / (1.0 x 10-12)] = 66 dB
The noise criteria for Children library is within NC50 - 55. Ther surrounding of market and corridors make up to Db66. Design strategy proposed to tackle this noise issue are DOUBLE SKIN Facade, fabric interior furnishings and interior partition walls.
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3.2 Reverberation Time Reverberation time is required to ensure sound delivered without interruption from noise source in the chosen space below.
3.2.1 OFFICE
Figure 3.3 Small Office Area near Reception. Room height = 4m Standard reverberation time for office = 0.8 - 1.2s Peak hour capacity = 10 Volume of office = (2.5x 3.4x 4.0)m =34m³ Material
Function
Plastered Cement Concrete
Ceiling Wall Column Table
Timber
Fabric Chair Concrete Cement Floor Finishes People Total sound absorption by material
Area /m² 8.5 20 1.7 2.5
Absorption Coefficient at 2000 Hz (S) 0.04 0.09 0.09 0.1
Sound Absorption (SA) 0.34 1.8 0.153 0.25
0.96 8.5
0.7 0.02
0.63 0.17
5
0.46
2.3 5.643
RT= (0.16xV)/ A A Where V = Volume of space; A = Total Absorption = S₁A₁ + S₂A₂ + S₃A₃ + … + SnAn Reverberation time (Peak Hour)
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RT= (0.16xV)/ A = (0.16x34)/5.643 = 0.96 The reverberation time for office meeting room during peak hour is 0.96 s. According to Acoustic Standard ANSI (2008), the optimum reverberation time of the office room during non-peak hour is 0.8-1.2s, hence it can be concluded that it has meet the requirement. 3.2.1 Discussion Room
Figure 3.4 Discussion Rooms
Room height = 4m Standard reverberation time for office = 0.8 - 1.2s Peak hour capacity = 10 Volume of office = (6x 6x 4.0)m =144mÂł Material
Function
Plastered Cement Concrete
Ceiling Wall Column Door Panels Table Chair Floor
Glass
Timber Fabric Carpet People Total sound absorption by material
Area /m² 36 56 1.6 2.1 10.4 4.8 2.025 36 10
Absorption Coefficient at 2000 Hz (S) 0.04 0.09 0.09 0.07 0.07 0.1 0.7 0.14 0.46
Sound Absorption (SA) 1.44 5.04 0.144 0.147 0.728 0.42 1.4175 5.04 4.6 18.98 25
RT= (0.16xV)/ A A Where V = Volume of space; A = Total Absorption = S₁A₁ + S₂A₂ + S₃A₃ + … + SnAn Reverberation time (Peak Hour) RT= (0.16xV)/ A = (0.16x144)/18.98 = 1.2
The reverberation time for office meeting room during peak hour is 1.2 s. According to Acoustic Standard ANSI (2008), the optimum reverberation time of the office room during non-peak hour is 0.8-1.2s, hence it can be concluded that it has meet the requirement.
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3.2 Sound Reduction Index (SRI) Transmission Loss Calculation required to determine sound level loss when passing through adjacent spaces with the effect of materials properties.
3.2.1 Multipurpose Hall
Activity noise Iᵢ= activity noise = 30dB Intensity: 30 = 10 log (lᵢ/io) Log(Iᵢ/1x10 ᴵ̄ ²)= 3 lᵢ = 1x10 ⁹̄ Human conversation lᵢ= human conversation = 65dB Intensity: 65 = 10 log(lᵢ/io) Log(lᵢ/ 1x10 ᴵ̄ ²)= 6.5 lᵢ = 3.16x10 ⁶̄ Total intensity= 1x10 ̄⁹ +3.16x10 ⁶̄ = 3.16x10 ⁶̄ SPL = 10 log (3.16x10 ⁶̄ /1x 10 ᴵ̄ ²) = 65dB
BUILDING ELEMENT WALL DOOR
MATERIAL SOUND REDUCTION INDEX, SRI GLASS 26dB GLASS 26dB
TRANSMISSION COEFFICIENT, T 2.51 x 10-3 2.51 x 10-3
AREA, S /M2 69.58 2.42
GLASS (WALL) SRI
= 10 log (1/T)
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= 10 log (1/T)
Antilog 2.6
= 1/T 27
3.98 x 102
= 1/T
T
= 2.51 x 10-3
GLASS (DOOR) SRI
= 10 log (1/T)
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= 10 log (1/T)
Antilog 2.6
= 1/T
3.98 x 102
= 1/T
T
= 2.51 x 10-3
Tav
= (69.58 x 2.51 x 10-3) + (2.42 x 2.51 x 10-3) 69.58 + 2.42 = 2.51 x 10-3
OVERALL SRI = 10log (1/T) = 10log (1 / 2.51 x 10-3) = 26 dB
As shown in calculations above, 26dB of noise level can be reduce during transmission from the external traffic and activity to the interior of the Multipurpose studio area. Therefore, the external noise (65dB) during peak hour, is reduced by 28dB during transmission, resulting in a sound level of 43dB when it reaches the studio. 37dB is within the range of recommend level for Studio area. Hence, acoustical comfort can be achieved by having walls as sound barriers. Additionally, the acoustic panel can be added as partition to barrier sound transmission from space to space.
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3.2.2 Discussion Room Wall type 1: concrete wall with insulation SRI=10 log (1/T) SRI concrete=52 52 = 10 log (1/Tconcrete) Log (1/Tconcrete) = 5.2 Tconcrete =6.32x 10 ⁶̄ Wall type 2: Glass Panels/ Doors SRI=10 log (1/T) S SRIglass=26 26 = 10 log (1/Tglass) Log(1/Tglass) =2.6 Tglass =2.51x10 ³̄
Surface Material Glass wall Concrete Wall Total
Surface Area (S) /m² 24.5 10 34.5
Transmission Coefficient 2.51x10 ³̄ 6.32x 10 ⁶̄
Surface area x Transmission coefficient (ST) 0.061 6.32x 10 ⁵̄ 0.061
Tav = (0.061/34.5) = 1.77x 10 ̄³ SRIoverall = 10 log (1/Tav) = 10 log(1/ 1.77x 10 ³̄ ) =28dB
As shown in calculations above, 28dB of noise level can be reduce during transmission from the external traffic and activity to the interior of the Discussion Room area. Therefore, the external noise (71dB) during peak hour, is reduced by 28dB during transmission, resulting in a sound level of 43dB when it reaches Discussion Room area. 42.48dB is within the range of recommend level for Studio area. Hence, acoustical comfort can be achieved by having walls as sound barriers.
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4.0 REFERENCES 1. Architects' Data. (2012). Chicester: John Wiley and Sons. 2. ASHRAE. (1995). ASHRAE handbook 1984 systems. Atlanta, GA: American Society Heating, Refrigerating &. 3. 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: MultiScience Publishing Co. Ltd. 4. Malaysia. (2007). Code of practice on energy efficiency and use of renewable energy for nonresidential buildings (first revision). Putrajaya: Department of Standard Malaysia. 5. Sound Absorption Coefficients of architectural accoustical materials. (1957). New York.
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