Building Science 2 Project 2: Integration with Design Studio 5

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

1.0 Lighting 1.1.1 Day Lighting (Informal Study Area) According to MS 1525, Daylight Factor distribution as below: Daylight Factor (%) >6 3-6 1-3 0-1

Distribution Very bright with thermal & glare problem Bright Average Dark

The selected area (Informal Study Area) located at first floor. This is an outdoor reading area, faรงades are openable to allow natural sunlight penetrate into this area. Hence, there are no artificial lighting will be using in this area.

Figure: First floor plan

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Figure: Section of informal study area

Daylight Factor Calculation Floor Area (m²) Area of façade that exposed to sunlight (m²) Exposed Façade to Floor Area Ratio/ Daylight Factor, DF

77 99 [(99) ÷ 77] = 1.286 = 128.6% x 0.1 = 12.86%

Natural Illumination Calculation Illuminance 120,000 lux 110,000 lux 20,000 lux 1,000 – 2,000 lux <200 lux 400 lux 40 lux <1 lux

Example Brightest sunlight Bright sunlight Shade illuminated by entire clear blue sky, midday 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/sunrise

E external = 20,000 lx DF = (Ei/Eo) x 100% DF

= 12.86 x 20 000 / 100 = 2572 lux

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Figure: Natural lighting contour diagram for informal study area

Conclusion The daylight contour diagrams is based on Dialux stimulation at 12pm, March. The Informal

Study Area has a daylight factor of 12.86 and natural illumination of 2572 lux. MS 1525 recommended illumination level for a study area is 400. This will cause thermal and glare problem. Hence, adjustable shading device is implemented to solve the glare problem and also to reduce the heat gain in this area.

Note Shadotimber is a fixed or controllable wooden louvre shading system that is proposed to install in front of the faรงade of the building. A shadotimber system can reduce solar heat gain, lower air conditioning running costs.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

1.1.2 Day Lighting (Play space) According to MS 1525, Daylight Factor distribution as below: Daylight Factor (%) >6 3-6 1-3 0-1

Distribution Very bright with thermal & glare problem Bright Average Dark

The selected area (Play space) is located at second floor. There is a skylight which bring the richness of natural sunlight into this area. Both facades for this area are openable and totally exposed to sunlight. Therefore, there are no need of artificial lighting in this area.

Figure: Second floor plan

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Figure: Section of play space

Daylight Factor Calculation Floor Area (m²) Area of façade that exposed to sunlight (m²) Area of skylight (m²) Exposed Façade & Skylight Area to Floor Area Ratio/ Daylight Factor, DF

42 46.35 18 [(46.35+18) ÷ 42] =1.532 = 153.2% x 0.1 = 15.32%

Natural Illumination Calculation Illuminance 120,000 lux 110,000 lux 20,000 lux 1,000 – 2,000 lux <200 lux 400 lux 40 lux <1 lux

Example Brightest sunlight Bright sunlight Shade illuminated by entire clear blue sky, midday 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/sunrise

E external = 20,000 lx DF = (Ei/Eo) x 100% DF

= 15.32 x 20 000 / 100 = 3064 lux

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Figure: Natural lighting contour diagram for play space

Conclusion The Play Space area has a daylight factor of 15.32 & natural illumination of 3064 lux. This will result in thermal and glare problem. Therefore, shading device and double glazed low e-value glass for skylight will be proposed to solve the glare problem and also to reduce the heat gain in this area.

Note Low-e coatings 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.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Task Lighting for infrequently used area

Lighting for working interiors

Localized lighting for exacting task

Illuminance (Lux) 20 100 100 100 100 150 100 100 100 100 200 200 300 – 400 300 – 400 150 200 150 – 300 150 150 100 100 300 – 500 200 – 750 300 500 1000 2000

Example of Applications Minimum service illuminance Interior walkway and car-park Hotel bedroom Lift interior Corridor, passageways, stairs Escalator, travellator Entrance and exit Staff changing room, locker and cleaner room, cloak room, lavatories, stores Entrance hall, lobbies, waiting room Inquiry desk Gate house Infrequent reading and writing General offices, shops and stores, reading and writing Drawing office Restroom Restaurant, canteen, cafeteria Kitchen Lounge Bathroom Toilet Bedroom Classroom, library Shop/ Supermarket/ Department store Museum and gallery Proof reading Exacting drawing Detailed and precise work

Table: Recommended average illuminance levels

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

1.2.1 Artificial Lighting (Café) The café located on the ground floor that from day to night. Although natural light can be acquired but it is insufficient. Hence, artificial lighting is vital for the space.

Figure: Ground floor plan

According to MS1525, the minimum lighting level required for a café is 200 lux. Type of luminaire used as showed below: Type of fixture Type of light bulb

LED Downlight

Material of fixture Product Brand & Code Nominal Life (Hours) Wattage Range (W) CRI Colour Temperature (K) Colour Designation Lumens

Aluminium LEDXION K01116 50,000 44 85 3000 Warm white 3735 Page | 8

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Material

Function

Colour

Area (m²)

Surface Type Reflective

Reflectance Value 0.30

Concrete finish Glass Timber Timber flooring Timber

Ceiling

Grey

28.91

Wall Wall frame Floor

Transparent 60.15 Brown 9.51 Brown 28.91

Absorptive Absorptive Absorptive

0.10 0.14 0.14

Furniture (table)

Brown

Absorptive

0.14

3.63

Table: Sample LLMF graphic

Lumen method and calculation for Café (from 1.5m height) Location Dimension

Area (A) Luminaries height Mounting height (Hm) Recommended average illumination levels by MS 1525 (E) Reflectance value

Café Length (L) = 5.9m Width (W) = 4.9m Height of the ceiling = 4.3m L x W = 5.9 x 4.9 = 28.91m² 4.3m 4.3 – 0.8 = 3.5m 200 lux Ceiling: 0.3, Floor: 0.14, Wall: 0.24

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Room index

đ??żđ?‘Ľđ?‘Š 5.9 đ?‘Ľ 4.9 = (đ??ż + đ?‘Š)đ??ťđ?‘š (5.9 + 4.9)3.5 = 0.8

Utilisation factor Maintenance factor

Type of light Number of light required

From table, UF = 0.26 Luminaire category = C (closed top reflector) Time between cleaning (years) = 1 đ?‘€đ??š = đ??żđ??żđ?‘€đ??š đ?‘Ľ đ??żđ?‘†đ??š đ?‘Ľ đ??żđ?‘€đ??š đ?‘Ľ đ?‘…đ?‘†đ?‘€đ??š đ?‘€đ??š = 0.7 đ?‘Ľ 1.0 đ?‘Ľ 0.89 đ?‘Ľ 0.9 đ?‘€đ??š = 0.56 LED light with 1 bulb, 3735 x 1 = 3735 lumen (F) đ??¸đ?‘Ľđ??´ đ?‘ = đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ?‘ =

200 đ?‘Ľ 28.91 3735 đ?‘Ľ 0.26 đ?‘Ľ 0.56

đ?‘ = 11 11 luminaries are needed to reach the minimum requirement for MS1525 = 200 lux Spacing to height ratio (SHR) đ?‘†đ??ťđ?‘… =

đ?‘†đ??ťđ?‘… =

1 đ??´ đ?‘Ľâˆš đ??ťđ?‘š đ?‘

1 28.91 đ?‘Ľâˆš 3.5 11 = 0.46

đ?‘†đ??ťđ?‘… =

Approximate fittings layout/m

� = 0.46 3.5

đ?‘† = 3.5 đ?‘Ľ 0.46 = 1.61 Fittings required along 5.9 m wall; 5.9 á 1.61 = 3.66 = 4 rows Therefore, approximately 4 x 3 = 12 luminaries required; Spacing along 4.9 m wall; 4.9 / 3 = 1.63 m Page | 10

CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Final layout

Figure: Fittings layout of café

Figure: Artificial lighting contour diagram for cafe

Conclusion 12 LED lights are used to illuminate the café to achieve the minimum of 200 lux stated by MS1525. With sufficient level of illumination, the users can enjoy food and good times in a well illuminated atmosphere.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

1.2.2 Multipurpose room The multipurpose located on the third floor that. Although natural light can be acquired but it is insufficient. Hence, artificial lighting is vital for the space.

Figure: Third floor plan

According to MS1525, the minimum lighting level required for a multipurpose room is 300 lux. Type of luminaire used as showed below: Type of fixture Type of light bulb

Fluorescent tube with reflector

Material of fixture Product Brand & Code Nominal Life (Hours) Wattage Range (W) CRI Colour Temperature (K)

Aluminium F39W/TS/830/ECO 36,000 39 85 3000 Page | 12

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Colour Designation Lumens

Warm white 3500

Material

Function

Colour

Area (m²) 132.28

Surface Type Reflective

Reflectance Value 0.30

Concrete finish Glass Timber Concrete Timber flooring

Ceiling

Grey

Wall Wall Wall Floor

Transparent Brown Grey Brown

29.24 79.55 79.55 132.28

Absorptive Absorptive Reflective Absorptive

0.10 0.14 0.30 0.14

Table: Sample LLMF graphic

Lumen method and calculation for Multipurpose room (from 1.5m height) Location Dimension

Area (A) Luminaries height Mounting height (Hm)

Multipurpose room Length (L) = 18.5m Width (W) = 7.15m Height of the ceiling = 4.3m L x W = 18.5 x 7.15 = 132.28m² 4.3m 4.3 – 0.8 = 3.5m Page | 13

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Recommended average illumination levels by MS 1525 (E) Reflectance value Room index

Utilisation factor Maintenance factor

300 lux Ceiling: 0.3, Floor: 0.14, Wall: 0.54 đ??żđ?‘Ľđ?‘Š 18.5 đ?‘Ľ 7.15 = (đ??ż + đ?‘Š)đ??ťđ?‘š (18.5 + 7.15)3.5 = 1.47 From table, UF = 0.4 Luminaire category = C (closed top reflector)

Time between cleaning (years) = 1

Type of light Number of light required

đ?‘€đ??š = đ??żđ??żđ?‘€đ??š đ?‘Ľ đ??żđ?‘†đ??š đ?‘Ľ đ??żđ?‘€đ??š đ?‘Ľ đ?‘…đ?‘†đ?‘€đ??š đ?‘€đ??š = 0.92 đ?‘Ľ 1.0 đ?‘Ľ 0.81 đ?‘Ľ 0.82 đ?‘€đ??š = 0.61 Fluorescent lamps with 2 bulbs, 3500 x 2 = 7000 lumen (F) đ??¸đ?‘Ľđ??´ đ?‘ = đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ?‘ =

300 đ?‘Ľ 132.28 7000 đ?‘Ľ 0.4 đ?‘Ľ 0.61

đ?‘ = 23 23 luminaries are needed to reach the minimum requirement for MS1525 = 300 lux Spacing to height ratio (SHR) đ?‘†đ??ťđ?‘… =

đ?‘†đ??ťđ?‘… =

1 đ??´ đ?‘Ľâˆš đ??ťđ?‘š đ?‘

1 132.28 đ?‘Ľâˆš 3.5 23 = 0.69

đ?‘†đ??ťđ?‘… =

� = 0.69 3.5

� = 3.5 � 0.69 = 2.42 Approximate fittings layout/m

Fittings required along 18.5 m wall; 18.5 á 2.42 = 7.64 = 8 rows

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Therefore, approximately 8 x 3 = 24 luminaries required; Spacing along 7.15 m wall; 7.15 / 3 = 2.38 m Final layout

Figure: Fittings layout for multipurpose room

Figure: Artificial lighting contour diagram for multipurpose room

Conclusion 24 fluorescent lamps are used to achieve minimum of 300 lux for this area according to MS1525. The whole floor area is well illuminated so that performance is not weakened due to poor lighting and comfort.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Table: Typical lumen maintenance and lamp survival data. (Source: SSL code for lighting, 2013)

Table: Luminaire categories and a list of typical locations where the various environmental conditions may be found (Source: SSL code for lighting, 2013)

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Table: Typical changes in light output from a luminaire caused by dirt deposition, for a number of luminaire and environment categories. (Source: SSL code for lighting, 2013)

Table: Typical changes in the illuminance from an installation that occur with time due to dirt deposition on the room surfaces. (Source: SSL code for lighting, 2013)

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Table: Utilization factor (UF) value. (source: Phillips, 2015)

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

1.3.1 Permanent Supplementary Artificial Lighting of Interiors (PSALI) 1.3.1 Formal study area

Figure: Formal study area- second floor plan

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Daylight Factor Calculation Floor Area (m²) Area of façade that exposed to sunlight (m²) Exposed Façade & Skylight Area to Floor Area Ratio/ Daylight Factor, DF

52.8 67.08 [(67.08) ÷ 52.8] = 1.27 = 127% x 0.1 = 12.7%

Natural Illumination Calculation

E external = 20,000 lx DF = (Ei/Eo) x 100% DF

= 12.7 x 20 000 / 100 = 2540 lux

Conclusion The formal study area has a daylight factor of 12.7% and natural illumination of 2540 lux. According to MS 1525, illumination level for a study area is 400. This will cause thermal and glare problem. Hence, adjustable shading device is implemented to solve the glare problem and also to reduce the heat gain in this area.

Artificial lighting According to MS 1525, the minimum lighting level required for a formal study area is 400. Type of luminaire used as showed below: Type of fixture Type of light bulb

Fluorescent tube with reflector

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Material of fixture Product Brand & Code Nominal Life (Hours) Wattage Range (W) CRI Colour Temperature (K) Colour Designation Lumens

Aluminium F39W/TS/830/ECO 36,000 39 85 3000 Warm white 3500

Material

Function

Colour

Area (m²) 52.5

Surface Type Reflective

Reflectance Value 0.30

Concrete finish Glass Timber Concrete Timber flooring

Ceiling

Grey

Wall Wall frame Wall Floor

Transparent Brown Grey Brown

58.56 8.52 79.36 52.8

Absorptive Absorptive Reflective Absorptive

0.10 0.14 0.30 0.14

Lumen method and calculation for Formal study area room (from 1.5m height) Location Dimension

Area (A) Luminaries height Mounting height (Hm) Recommended average illumination levels by MS 1525 (E) Reflectance value Room index

Formal study room Length (L) = 16m Width (W) = 3.3m Height of the ceiling = 4.3m L x W = 16 x 3.3 = 52.5m² 4.3m 4.3 – 0.8 = 3.5m 400 lux Ceiling: 0.3, Floor: 0.14, Wall: 0.54 đ??żđ?‘Ľđ?‘Š 16 đ?‘Ľ 3.3 = (đ??ż + đ?‘Š)đ??ťđ?‘š (16 + 3.3)3.5 = 0.78

Utilisation factor Maintenance factor

From table, UF = 0.3 Luminaire category = C (closed top reflector)

Time between cleaning (years) = 1

Type of light

đ?‘€đ??š = đ??żđ??żđ?‘€đ??š đ?‘Ľ đ??żđ?‘†đ??š đ?‘Ľ đ??żđ?‘€đ??š đ?‘Ľ đ?‘…đ?‘†đ?‘€đ??š đ?‘€đ??š = 0.92 đ?‘Ľ 1.0 đ?‘Ľ 0.81 đ?‘Ľ 0.82 đ?‘€đ??š = 0.61 Fluorescent lamps with 2 bulbs, 3500 x 2 = 7000 lumen (F) Page | 21

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Number of light required

đ?‘ = đ?‘ =

đ??¸đ?‘Ľđ??´ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š

400 đ?‘Ľ 52.5 7000 đ?‘Ľ 0.3 đ?‘Ľ 0.61

đ?‘ = 16 16 luminaries are needed to reach the minimum requirement for MS1525 = 400 lux Spacing to height ratio (SHR) đ?‘†đ??ťđ?‘… =

đ?‘†đ??ťđ?‘… =

1 đ??´ đ?‘Ľâˆš đ??ťđ?‘š đ?‘ 1 52.5 đ?‘Ľâˆš 3.5 16

= 0.52 đ?‘†đ??ťđ?‘… =

� = 0.52 3.5

� = 3.5 � 0.52 = 1.82 Approximate fittings layout/m

Fittings required along 16 m wall; 16 á 1.82 = 8.79 = 9 rows Therefore, approximately 9 x 2 = 18 luminaries required; Spacing along 3.3 m wall; 3.3 / 2 = 1.65 m

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Final layout

Figure: Fittings layout for formal study area

Figure: PSALI contour diagram for formal study area

Conclusion 18 fluorescent lamps are used to illuminate the formal study area to achieve the minimum of 400 lux stated by MS 1525. With sufficient level of illumination, the users can enjoy reading in a comfortable environment. This area is supplemented by the natural lighting which hence will switch from artificial lighting use to the natural one.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.0 Acoustics 2.1 External Noise (Sound Pressure Level) 2.1.1 Cafe Noise source:

Figure: CafĂŠ- ground floor plan

a) Back alley (wet market)

= 60 dB 60

= 10log (l1 / l0)

Antilog 6

= [l1 / (1.0 x 10-12)]

1 x 106

= [l1 / (1.0 x 10-12)]

l1

b) Public space

= 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

= 3.16 x 10-6 Page | 24

CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Total intensities, I

= (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

Conclusion The noise criteria for café is within the range of NC-45-NC-50 (medium loud). The combined SPL of the wet market and public space surrounding the café = 66dB, exceeds the noise criteria for the café, making discussions communications not possible. To reduce the noise produced by the street and market, green wall and the sound transmitting properties of the facades of the café need to be considered so as to mask the exterior noise.

Note Vegetated facades reduce noise from all sourced situated outside the café, act as sound barrier walls reflect and deflect noise.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.1.2 Informal study area

Figure: Informal study area- first floor plan

Noise source: 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) Corridors

= 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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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Total intensities, l

= (1.0 x 10-5) + (3.16 x 10-6) = 1.32 x 10-5

Combined SPL

= 10log (l1 / l0) = 10log [(1.32 x 10-5) / (1.0 x 10-12)] = 71 dB

Conclusion The noise criteria for a study area is within the range of NC-35 – NC- 40. The combined SPL of the traffic noise and the corridors surrounding the study area = 71dB, exceeds the noise criteria for the children’s area, making discussion and learning hardly possible. Design strategies such as design a courtyard which acts as buffer zone and double façade to filter and deflect noise.

Note 1. Shrubs- Have thick, waxy leaves, dense evergreen foliage and branches to filter the noise when it is transmitted into the buildings 2. Trees- Plantings of two staggered rows where space allowed to provide visual screening, it is more efficient to reduce noise. 3. Double skin- The cavity of the double skin façade is only ventilated to the outside and is built to reduce noise.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.2 Reverberation time, RT

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Table: Sound absorption coefficient

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.2.1 Multipurpose room

Figure: Multipurpose room- third floor plan

Component

Material

Wall Floor Ceiling People peak

Surface area/m² [A] or quantity Plaster wall (7.1+14.3+7.1) x 4.5= 128.25 Carpet 7.1 x 14.3= 101.53 Concrete 101.53 35 Total absorption [A]

Absorption coefficient [S] (500 Hz) 0.06

Sound absorption [SA]

0.14

14.20

0.30 0.5

30.42 17.50 69.82

7.70

Volume = area of the room x height = 101.53 x 4.5 = 456.89 máľŒ

RT

�

= 0.16 đ??´ = 0.16 x

456.89 69.82

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

= 1.05 s

Conclusion The reverberation time for the multipurpose room in 500 Hz of absorption coefficient is 1.05s. According to the standards of reverberation time, the standard comfort reverberation for multipurpose room is between 1.6-1.8s. So the reverberation time of the multipurpose room on 500 Hz is within the standard comfort reverberation time.

2.2.2 Electronic laboratory

Figure: Electronic laboratory- first floor plan

Component

Material

Wall

Plaster wall

Surface area/m² [A] or quantity (3.22 + 2.6 + 2) x 4.3= 33.63

Absorption coefficient [S] (500 Hz) 0.06

Sound absorption [SA] 2.02

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Glass Floor Ceiling People peak

(10.2 + 12.2) x 4.3 = 96.32 Carpet 12 x 5.2 = 62.4 Concrete 62.4 20 Total absorption [A]

0.04

3.85

0.14 0.30 0.5

8.74 18.72 10 43.33

Volume = area of the room x height = 62.4 x 4.3 = 268.32 máľŒ

RT

�

= 0.16 đ??´ = 0.16 x

268.32 43.33

= 0.99 s

Conclusion The reverberation time for the electronic laboratory in 500 Hz of absorption coefficient is 0.99s. According to the standards of reverberation time, the standard comfort reverberation for electronic laboratory is between 1.0 – 1.2s. So the reverberation time of electronic laboratory on 500 Hz is within the standard comfort reverberation time.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.3 Sound Reduction Index (SRI)

Figure: Recommended NC level for space

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.3.1 Café

Figure: Café- ground floor plan

The sound pressure level of café is 40 – 45dB according to MS1525 standards. Components Material

Area (m²)

Wall

Brick

Wall

Glass

Door

Glass

2.9 x 4.5= 13.05 4.3 x 4.5= 19.35 (5.8 + 5.9) x 4.5= 52.65

Sound Reduction Index (SRI) 42dB

Transmission Coefficient, T

26dB

2.51 x 10-3

26dB

2.51 x 10-3

6.31 x 10-5

Transmission coefficient of materials a) Brick (wall) SRI

= 10 log (1/T)

42

= 10 log (1/T)

Antilog 4.2

= 1/T

T

= 6.31 x 10-5 Page | 34

CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

b) Glass (wall) SRI

= 10 log (1/T)

26

= 10 log (1/T)

Antilog 2.6

= 1/T

T

= 2.51 x 10-3

c) Glass (door) SRI

= 10 log (1/T)

26

= 10 log (1/T)

Antilog 2.6

= 1/T

T

= 2.51 x 10-3

Average transmission coefficient of materials Tav

= (13.05 x 6.31 x 10-5) + (19.35 x 2.51 x 10-3) + (52.65 x 2.51 x 10-3) 13.05 + 19.35 + 52.65 = 2.26 x 10-3

Total surface reflection index, SRI SRI (overall) = 10 log (1/Tav) = 10 log (1/ 2.26 x 10-3) = 26.5dB Noise level in Café = 66dB – 26.5dB = 39.5dB

After transmission loss, the sound pressure level of the café is 39.5dB. According to MS1525, the standard SPL for café is 40 – 45 dB, thus the space meets the requirements.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

2.3.2 Informal study area

Figure: Informal study area- first floor plan

The sound pressure level of open plan study room is 35 – 40dB according to MS1525 standards. Components Material

Area (m²)

Wall

Brick

Window

Single laminated glass

(4.5 + 3.3 + 3.5 + 3.5) x 4.5= 66.6 12.5 x 4.5= 56.25

Sound Transmission Reduction Index Coefficient, T (SRI) 42dB 6.31 x 10-5

35dB

3.61 x 10-4

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

Transmission coefficient of materials a) Brick (wall) SRI

= 10 log (1/T)

42

= 10 log (1/T)

Antilog 4.2

= 1/T

T

= 6.31 x 10-5

b) Single laminated glass (window) SRI

= 10 log (1/T)

35

= 10 log (1/T)

Antilog 3.5

= 1/T

T

= 3.16 x 10-4

Average transmission coefficient of materials Tav

= (66.6 x 6.31 x 10-5) + (56.25 x 3.16 x 10-4) 66.6 + 56.25 = 1.79 x 10-4

Total surface reflection index, SRI SRI (overall) = 10 log (1/Tav) = 10 log (1/ 1.79 x 10-4) = 37.5dB Noise level in Informal study area = 71dB – 37.5dB = 33.5dB The transmission loss from the front and back street is 37.5dB. After transmission loss, the sound pressure level of the informal study area is 33.5dB. According to MS1525, the standard SPL for open study area is 35 – 40 dB, thus it meets the requirements.

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CHEAH HOONG FEI (0311690) BUILDING SCIENCE 2

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: Multi-Science Publishing Co. Ltd. 4. Malaysia. (2007). Code of practice on energy efficiency and use of renewable energy for non-residential buildings (first revision). Putrajaya: Department of Standard Malaysia. 5. Sound Absorption Coefficients of architectural acoustical materials. (1957). New York.

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