Final building science report

BUILDING SCIENCE 2 (ARC 3413)

PROJECT 2 INTEGRATION WITH DESIGN STUDIO 5

SENTUL COMMUNITY LIBRARY

FINAL REPORT & CALCULATION

NAME: SEN YIH YIING

STUDENT ID: 0318890

TUTOR: MR SIVA

Content

1.0 Introduction 1.1 Propose Floor Plans

2.0 Calculation And Analysis 2.1 Sunpath Diagrams 2.2 Daylighting 2.2.1 Daylighting Factor, DF 2.2.2 Natural Illumination 2.2.3 Daylighting In Meeting Room (1st Floor Level) 2.2.4 Daylighting at Café Area (Ground Floor Level) 2.3 Artificial Lighting 2.3.1 Room Index And Utilization Factor 2.3.2 Lumen Method 2.3.3 Artificial Lighting At Workshop 2.3.4 Artificial Lighting At Office 2.4 PSALI 2.4.1 PSALI At Cafe 2.4.2 PSALI At Workshop

3.0 Acoustic 3.1 Reverberation Time 3.1.1 Reverberation Time In Office 3.1.2 Reverberation Time In Meeting Room 3.2 Sound Reduction Index 3.2.1 Sound Reduction Index Between Meeting Room & Quiet Reading Space 3.2.2 Sound Reduction Index Between office and Public Realm 3.3 Sound Pressure Level (Exterior) 3.3.1 Front Façade, Jalan Sultan Azlan Shah (Peak Hour) 3.3.2 Back Façade , Backlane (Non Peak Hour)

4.0 Reference

1.0 INTRODUCTION

Building Science 2 introduce students to the knowledge in applying optimum acoustic and lighting into their design, which can be clearly potrait in this report, where the research on the intergration of acoustic and lighting performances with the implementions in students’ Studio 5 design.

JALAN IPOH

Figure 1 Site Location and View to Site

The final project in Studio 5 is to design an urban infill community library in an urban city, which in this case, in Jalan Sultan Azlan Shah, Sentul. The road is an essential connection between suburban cities suach as Damansara, Kepong to Kuala Lumpur, not only there are vehicles packed on the road, but there are also locals passing by as there are rows of shophouses located along the street. This embarks the issue in the acoustic performance of the community library design, in terms to reduce the chaotic external noise.

Furthermore, as the design is an urban infill, where there are only the front and back facades are exposed to natural lighting. Therefore, issues and solutions to introduce optimum lighting into the community library design are also discussed in this report.

1.1 PROPOSE FLOOR PLANS

LOWER GROUND FLOOR PLAN SCALE 1:500

GROUND FLOOR PLAN SCALE 1:500

1ST FLOOR PLAN SCALE 1:500

2ND FLOOR PLAN SCALE 1:500

2.0 CACULATION AND ANALYSIS

2.1 SUNPATH DIAGRAM

Shadows are formed at the south west, site is not shaded

Larger shadows are formed at the south west , site is not shaded

View To Site

Street View To Site

Large area of shadows are formed at the north east, site is shaded

The site is not well shaded with the neighbouring buildings during daytime because of the surrounding buildings are not tall in height. There are rows of trees and greeneries along the road which could provide aesthetic view as well as for minor sun shading.

Therefore, better faรงade design strategies are to imply in the community library design to prevent excessive sun exposure.

2.2 DAYLIGHTING

2.2.1 DAYLIGHTING FACTOR, DF

DF = (Ei/Eo) x 100%

Where, Ei = illuminance due to daylight at a point on the indoors working plane; Eo = simultaneous outdoor illuminance on a horizontal plane from an unobstructed hemisphere of overcast sky.

Zone DF (%) Distribution Very Bright >6 Very large with thermal and glare problems Bright 3 – 6 Good Average 1 – 3 Fair Dark 0 - 1 Poor NOTE: The figures are average daylight factors for windows without glazing.

Table 2.1 Daylight Factors and Distribution (Source: “MS 1525”, 2007.)

2.2.2 NATURAL ILLUMINATION

Illuminance 120000 lux 110000 lux 20000 lux 1000-2000 lux <200 lux 400 lux 40 lux <1 lux

Example Brightest sunlight Bright sunlight Shade illuminated by entire clear blue sky Typical overcast day, midday Extreme of darkest storm clouds, midday Sunrise or sunset on clear day (ambient illumination) Fully overcast, sunset or sunrise Extreme of darkest storm cluds, sunset or sunsunrise Table 2.2 Natural Illuminance Level Example

Table 2.3 Recommended values of illuminance

(Source: http://www.electricneutron.com/lighting-2/level-of-illuminance-for-industrial-lighting/)

2.2.3 DAYLIGHTING IN MEETING ROOM (1st Floor Level)

Meeting Room

Figure 2.2 Rear Elevation Faรงade Figure 2.1 1st Floor Plan (N.T.S)

Design Meeting Room

(Perforated Fiberglass Concrete)

Panels)

The selected meeting room is located at the 1st floor of the building, facing the back lane through the perforated faรงade panels. As the site is constantly expose to the sun without much shading medium from the surrounding site, fiberglass concrete faรงade panels acts as a shading device to the building. The fiberglass concrete perforated faรงade has circular holes with diameter of 600mm, allowing strips of natural lighting to penetrate in and illuminates the space. The size of the holes also allow comfortable permeable view between inside and outside, so the occupants will not feel being isolated.

Daylight Factor Calcultion, DF

Floor Area (m2), Eo

Faรงade Area Allows For Sunlight Penetration, Ei

Daylight Factor. DF (%)

Natural illumination Calculation, EEi

Daylight Factor, DF (%)

Daylight Level In Malaysia, E0 (lux)

Daylighting illumination

26.508 m2 5.655 m2 (Ei/Eo) x 100% =(5.655/ 26.508) x 100% = 21.33%

DF = 21.33% x 0.1 = 2.13%

2.13% 32000 lux EEi = (DF x E0)/ 100 = (2.13 x 32000)/ 100 = 681.6 lux

The conclusion of the calculation in daylight factor of the meeting room is 2.13% which falls at the fair daylight distribution, where glare will not occur, providing suitable space for occupants to stay in and conduct long discution.

The calculated daylighting illumination is 681.6 lux. Based on the recommended values of illuminance according to the activity of the space, meeting room is consider as a casual work category, where the recommended illuminance is 200 lux. However, the calculated daylighting illuminance in the meeting room is 681.6 lux, which is 3 times the recommended illuminance level of the space.

This may be because that the area of the meeting room is small in size and there are too much penetration of sunlight to the space. However, since the meeting is facing the back lane, where shadow may form from the lighting angle to the adjacent building, providing potential sun shading strategy to the space.

2.2.4 DAYLIGHTING AT CAFÉ AREA (Ground Floor Level)

Cafe

Figure 2.3 Ground Floor Plan (N.T.S) Cafe

Figure 2.4 Front Elevation Façade Design (Glass French Window)

The café is located at the ground floor of the building, as a visual invitation for the people to visit the community library. The space is facing the main road, Jalan Sulatan Azlan Shah, where has high risk of sun exposure. But with the suspended perforated concrete panels blocking the direct sunlight, the café space may be comfortable to be in.

To achive this design idea, rows of glass french door is added on the façade to make the visual permeability to the space, as well as to a sense of lightness, which corresponds to the flowy interior design.

Daylight Factor Calcultion, DF

Floor Area (m2), Eo

Faรงade Area Allows For Sunlight Penetration, Ei

Daylight Factor. DF (%)

Natural illumination Calculation, EEi

Daylight Factor, DF (%)

Daylight Level In Malaysia, E0 (lux)

Daylighting illumination

55.137 m2 45.158 m2 (Ei/Eo) x 100% =(45.158/ 55.137) x 100% = 81.9%

DF = 81.9% x 0.1 = 8.19%

8.19% 32000 lux EEi = (DF x E0)/ 100 = (8.19 x 32000)/ 100 = 2620.8 lux

The conclusion of the calculation in daylight factor of the cafe is 8.19% which falls at the very bright daylight distribution, where uncomfortable glare may occur, causing occupants to be less comfortable to stay long.

Based on the recommended values of illuminance according to the activity of the space, meeting room is consider as a casual work category, where the recommended illuminance is 200 lux. However, the calculated daylighting illuminance in the meeting room is 2620.8 lux, which is 10 times the recommended illuminance level of the space.

The above statement may be resulted from the large area of glass french windows, but this is the purpose of the space, as a visual entrance to welcome people to the library. But with the suspended perforated concrete panels which covers about a quarter of the height of the french windows and also the planted trees on the lanscape, there would be lower chance of extreme sun exposure within the space, and glare will not occur.

2.3 ARTIFICIAL LIGHTING

2.3.1 ROOM INDEX AND UTILIZATION FACTOR

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Where, L = room length

W = room width

Hm = mounting height of fitting (from working plans)

Work Plane = Desk or Bench Height

Figure 2.5 Utilization Factor Table For Reference

2.3.2 LUMEN METHOD

E =

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Where, E = average illuminance over the horizontal working place

n = number of lamps in each luminaire

N = number of luminaire

F = lighting design lumens per lamp, ie. Initial bare lamp luminous

UF = utilization factor for the horizontal working plane

LLF = light loss factor

A = area of horizontal working plane

2.3.3 ARTIFICIAL LIGHTING AT WORSHOP

Figure 2.5 Lower Ground Floor Plan (N.T.S)

Workshop

The workshop is located at the lower ground level, where th reception of natural lighting is very limited. As the space is located underneath the entrace staircase which leads to the ground floor level, the rise of the staircase, which made of glass blocks is the only natural light source to the space. Therefore, artificial lighting is needed to illuminate the space where classes and society activity will be conducted.

According to MS1525, the minimum illuminance level requirement for a class is 300 lux.

Type of Fixture Type of Light Bulb

Lumen

Top Mount LED Downlight

DL25-02 (25W, PAR56 LED)

Heavy PAR 56 Casing and Halogen 300W bulbs 1200 lm

Lumen Method And Room Index Calculation Dimension of room (L x W) Total Floor Area Activity of the space Ceiling Height Mounting Height, Hm Height of Work Level Lumen of Lighting Fixture Standard illuminance Level Reflection Fators Room Index Utilization Factor, UF Maintenance Factor, MF Lumen Method

6.59m x 7.93m 52.26m2 Community classes, academic and activity workshop 3.0m 2.8m 0.75m 1200 lm

300 lux Ceiling: Polished Wooden Claded Ceiling (0.5) Wall: Polished Wooden Claded Wall (0.5) Floor: Polished Wooden Flooring (0.5) (6.59 x 7.93)/ (2.8 x (6.59 + 7.93)) = 1.28 0.46 0.8 N = (E x A)/ (F x UF x MF) = (300 x 52.26)/ (1200 x 0.46 x 0.8) = 15678/ 441.6 = 35.5 = 36 lamps

From the calculation, a minimum of 36 luminaires with 1200lm is required to illuminate the worshop area.

Spacing To Height Ratio

SHR = (1/Hm) x â&#x2C6;&#x161;(A/N) = (1/2.8) x â&#x2C6;&#x161;(52.26/36) = 0.43

S/H = 0.43 S = 0.43H S = 0.43 x 2.8 S = 1.2m

The spacing between each luminaire is 1.2m.

Row of lamp = 6.59/ 1.2 = 5.49 = 6 rows

Number of lamps at each row = 36 lamps / 6 rows = 6 lamps

The plotted drawing based on the calculated number of luminaires required in the space is shown below:

Figure (A) Lighting Layout On Workshop Plan (N.T.S)

Figure (B) Lighting Contour On Workshop Plan (N.T.S)

2.3.4 Artificial Lighting At Office

Figure 2.6 Lower Ground Floor Plan (N.T.S) Office

The office is not only as the official working space for the library, but also as the staff pantry for the workers. The office is also located at lower ground floor, but the space has no external natural lighting to penetrate in, therefore, artificial lighting is essential to illuminate the working space.

According to MS1525, the minimum illuminance level requirement for an office is 300 lux.

Type of Fixture Type of Light Bulb

Lumen

Fluorescent Tube Light

Philips TL-D 36W/54-765 1SL/25

G13 Medium Bi-Pin Fluorescent 2500 lm

Lumen Method And Room Index Calculation Dimension of room (L x W) Total Floor Area Activity of the space Ceiling Height Mounting Height, Hm Height of Work Level Lumen of Lighting Fixture Standard illuminance Level Reflection Fators Room Index Utilization Factor, UF Maintenance Factor, MF Lumen Method

2.7m x 5.65m 15.26m2 Office working space, staff pantry 3.0m 2.8m 0.75m 2500 lm

300 lux Ceiling: Polished Wooden Claded Ceiling (0.5) Wall: Polished Wooden Claded Wall (0.5) Floor: Matt Tile Flooring (0.5) (2.7 x 5.65)/ (2.8 x (2.7 + 5.65)) = 0.65 0.28 0.8 N = (E x A)/ (F x UF x MF) = (300 x 15.26)/ (2500 x 0.28 x 0.8) = 4578/ 560 = 8.175 = 8 lamps

From the calculation, a minimum of 8 luminaires with 2500lm is required to illuminate the worshop area.

Spacing To Height Ratio

SHR = (1/Hm) x √(A/N) = (1/2.8) x √(15.26/8) = 0.49

S/H = 0.49 S = 0.49H S = 0.49 x 2.8 S = 1.372m = 1m

The spacing between each luminaire is 1m.

Row of lamp = 2.7/ 1 = 2.7 = 3

Number of lamps at each row = 8 lamps / 3 rows = 3 lamps

The plotted drawing based on the calculated number of luminaires required in the space is shown below:

Figure (A) Lighting Layout On Office Plan (N.T.S)

Figure (B) Lighting Contour On Office Plan (N.T.S)

2.4 PSALI

2.4.1 PSALI AT CAFÉ

Daylight Factor (DF) = (Ei/E0) x 100%

Floor Area Area Of Glass Window Daylight Factor, DF

55.137 m2 45.158 m2 (Ei/Eo) x 100% =(45.158/ 55.137) x 100% = 81.9%

DF = 81.9% x 0.1 = 8.19%

An optimum and comfortable lighting level for a café is essential to keep the occupants relax and enjot their time within the space. The result of the daylighting factor is at 8.19%, which is located at the very uncomfortable brightness based on the requirement by MS 1525:2007

However, the suspended perforated concrete panel which covers almost half of the curtain french window and the trees in front of the landscape may cause the the daylight factor at the café to be much lower. Furthermore, the café is facing north east, which mainly exposed to the morning sunlight, which means duriing the afternoon and evening time, there may be not enough lighting level at the space.

Therefore, a few number of artificial luminaire could be added into the space to enhance the environment permance of the café.

EEi = (D x E0)/ 100

Ei = (8.19 x 32000)/ 100 = 2620.8lux

The standard illuminance level for a café is 200lux, but the caluculated daylighting may received is 2620.8 lux, which is 10 times than the requirement. As a solution, the susoended perforated concrete panel can be elongated to cover much larger area of the curtain french window or add brise soleil on the window to reduce sun exposure.

Figure (A) Lighting Layout On Cafe Plan (N.T.S)

Figure (B) Natural And Artificial Lighting Layout On Cafe Plan (N.T.S)

2.4.2 PSALI AT WORKSHOP

Floor Area Area Of Glass Window Daylight Factor, DF

52.26 m2 18.39 m2 (Ei/Eo) x 100% =(18.39/ 52.26) x 100% = 35.19%

DF = 35.19% x 0.1 = 3.52%

As there will be classes and workshops held in the space, there should be optimum and clear lighting within the space as it is an academic and activity space. While with the resulted daylighting factor, 3.53 is located at the bright and good category, which is great for the usage of the space. As to add additional luminaires to the space, as a backup during unpredictable times, artificial lighting should be consider to enhance the brightness of the space.

EEi = (D x E0)/ 100 Ei = (3.52 x 32000)/ 100 = 1126.4 lux

The standard illuminance level for a class or studio is 300lux, but the resulted daylighting level is 1126.4lux, which is 3 times the recommended lighting level for the space. Hoever, as the workshop is located under ground, and the light source is passes through the glass blocks as the rise of the stairs, that may add some poectic feeling to the space with the intersection of light and shadow stripes. Furthermore, the natural lght passes through is not directed to the ground, instead, it is directed to the ceiling as the sunlight is from the rise of the stairs. Therefore, I do not recommend further sun shading strategy to the space.

Figure (A) Lighting Layout On Workshop Plan (N.T.S)

Figure (B) Natural And Artificial Lighting Layout On Workshop Plan (N.T.S)

3.0 Acoustic

3.1 Reverberation Time

RT = (0.16 x V)/ A Where V = volume of the space A = Total Area Of Acoustic absorption Elements

According to ISO 354, the standard reverberation time is within 1.0s- 1.5 s.

3.1.1 Reverberation Time in Office

Peak Hour Reverberation Time Office (Lower Ground Floor) 2 Total Floor Area (m ) 15.26 m2 Total Volume (m3) 15.26 x 3.0= 45.78 m3 Materials (Wall) Acoustic Area, S (m2) Area, S x Absorption

Absorption Coefficient, a Coefficient, a (500Hz) Wooden Wall 0.08 47.88 3.83 Cladding Sliding Door Glass 0.06 1.45 0.087 Wood 0.08 0.53 0.042 Material (Roof) Wooden Ceiling 0.08 Material (Floor) Homogeneous 0.03 Floor Tiles Material (Furniture) Steel Table And 0.22 Chairs Occupants 0.42

15.26

1.22

15.26

0.46

2.03

0.45

Peak Hour: 5 2.1 Non-Peak Hour: 0.84 2

RT = (0.16 x V)/ A = (0.16 x 45.78)/8.19 = 0.89s Non-Peak Hour Reverberation Time RT = (0.16 x V)/ A = (0.16 x 45.78)/ 6.93 = 1.06s

Total Absorption, A

8.19 6.93

The reverberation time for office in 500Hz absorption coefficient in peak and non-peak hour are 0.89s and 1.06s respectively. The reverberation time during peak hour does not falls within the standard reverberation time of 1.0s â&#x20AC;&#x201C; 1.5s. However, during non-peak hour, the reverbrartion time is optimum.

3.1.2 Reverberation Time in Meeting Room Meeting Room (1st Floor Level) Total Floor Area (m2) 26.51 m2 Total Volume (m3) 26.51 x 4.18= 110.80 m3 Materials (Wall) Acoustic Area, S (m2) Area, S x Absorption

Absorption Coefficient, a Coefficient, a (500Hz) Painted 0.02 94.89 1.90 Concrete Sliding Door Glass 0.06 1.45 0.087 Wood 0.08 0.53 0.042 Material (Roof) Wooden Ceiling 0.08 Material (Floor) Carpet 0.3 Material (Furniture) Steel Table And 0.22 Chairs Occupants 0.42

Peak Hour Reverberation Time RT = (0.16 x V)/ A = (0.16 x 110.8)/14.97 = 1.18s Non-Peak Hour Reverberation Time RT = (0.16 x V)/ A = (0.16 x 110.8)/ 13.29 = 1.25s

26.51

2.12

26.51

7.95

1.57

0.35

Peak Hour: 6 2.52 Non-Peak Hour: 0.84 2

Total Absorption, A

14.97 13.29

The reverberation time for meeting room in 500Hz absorption coefficient in peak and non-peak hour are 1.18s and 1.25s respectively. Both of the reverberation tim are within the standard reverberation time of 1.0s â&#x20AC;&#x201C; 1.5s. Provides optimum reverberation comfort to the occupants.

3.2 Sound Reduction Index

3.2.1 Sound Reduction Index Between Meeting Room & Quiet Reading Space Materials

SRI (dB)

(Wall) Painted

44

Surface

Tranmission

Area, S (m2)

Coefficient

2.07

concrete

T

3.98 x 10-5

TL = 10log10 (1/T)

44 = 10log10 (1/T) log10 (1/T) = 4.4 1/T = 104.4 T = 3.98 x 10-5

Glass Door

26

1.45

2.51 x 10-3

TL = 10log10 (1/T) 26 = 10log10 (1/T) log10 (1/T) = 2.6 1/T = 102.6 T = 2.51 x 10-3

Wooden Panel

31

0.53

7.943 x 10-4

TL = 10log10 (1/T) 31 = 10log10 (1/T) log10 (1/T) = 3.1 1/T = 103.1 T = 7.94x 10-4

T = [(2.07 x 3.98 x 10-5)+(1.45 x 2.51 x 10-3)+(0.53x 7.943 x 10-4)]/ (2.07+1.45+0.53) = 1.023 x 10-3

The calculated overall SRI between meeting room Overall SRI = 10log(1/T) and public reading space is 29.9dB. Where if the the = 10log(1/1.023 x 10-3) wall can only block 29.9dB of noise from the the meeting room to the quiet public reading area, in = 29.9dB terms to ensure the conversation privacy of the

occupants in the meeting room, acoustic panel are

advice to be implied to the wall that seperates meeting room and quiet reading space.

3.2.2 Sound Reduction Index Between office and Public Realm Materials

SRI (dB)

(Wall) Wooden

31

Surface Area,

Tranmission

S (m2)

Coefficient

6.68

7.943 x 10-4

T TL = 10log10 (1/T)

Claded

31 = 10log10 (1/T)

concrete wall

log10 (1/T) = 3.1 1/T = 103.1 T = 7.94x 10-4

Glass Door

26

1.45

2.51 x 10-3

TL = 10log10 (1/T) 26 = 10log10 (1/T) log10 (1/T) = 2.6 1/T = 102.6 T = 2.51 x 10-3

Wooden Panel

31

0.53

7.943 x 10-4

TL = 10log10 (1/T) 31 = 10log10 (1/T) log10 (1/T) = 3.1 1/T = 103.1 T = 7.94x 10-4

T = [(6.68 x 7.943 x 10-4)+(1.45 x 2.51 x 10-3)+(0.53x 7.943 x 10-4)]/ (6.68+1.45+0.53) = 1.082 x 10-3

The calculated overall SRI between office and public Overall SRI = 10log(1/T) realm is 29.66dB. Where the the wall can only block 29.66dB of noise from the public realm to the quiter = 10log(1/1.082 x 10-3) office, in terms to maintain quietness to the office, = 29.66dB additional material alteration such as adding padding

on the wall to prevent excess noise penetration.

3.3 Sound Pressure Level, SPL (External Noise)

According to Acoustic Standard ANSI (2008) S12.2-2008, the standard sound pressure level of each building usage are listed as below:

Figure 2.7 Standard SPL at each building usage according to ANSI (2008) Source: https://web.iit.edu/sites/web/files/departments/academicaffairs/Academic%20Resource%20Center/pdfs/Workshop_-_Acoustic.pdf

Community Library may fall in the small and private building category, therefore, the maximum sound pressure level for community library is 35-44dB.

3.3.1 Front Faรงade, Jalan Sultan Azlan Shah (Peak Hour)

a. Highest Reading = 82dB

SPL = 10log10 (l/l0) 82 = 10log10 (l/1 x 10-12) l = 108.2 x 1 x 10-12 = 1.58 x 10-4

b. Lowest Reading = 58dB

SPL = 10log10 (l/l0) 58 = 10log10 (l/1 x 10-12) l = 105.8 x 1 x 10-12 = 6.31 x 10-7

Total Intensity, I = 1.58 x 10-4 + 6.31 x 10-7

= 1.59 x 10-4

Combined SPL = 10log10 (l/l0)

= 10log10 [(1.59 x 10-4)/ (1 x 10-12)

= 82 dB

3.3.1 Back Façade, Backlane (Non-Peak Hour)

a. Highest Reading = 57dB

SPL = 10log10 (l/l0) 57 = 10log10 (l/1 x 10-12) l = 105.7 x 1 x 10-12 = 5.01 x 10-7

b. Lowest Reading = 42dB

SPL = 10log10 (l/l0) 42 = 10log10 (l/1 x 10-12) l = 104.2 x 1 x 10-12 = 1.58 x 10-8

Total Intensity, I = 5.01 x 10-7+ 1.58 x 10-8

= 5.17 x 10-7

Combined SPL = 10log10 (l/l0)

= 10log10 [(5.17 x 10-7)/ (1 x 10-12)

= 57.13 dB

The conclusion of the result calculated from combine SPL is that for the front façade, the combined SPL is 82dB while the back lane is much lower than the front façade, 57.13dB, because there are less people and almost no vehile pass by during day or night. The noise receives from the front façade is a combination of traffics and passerby while the back lane is just minimal passerby.

The optimum SPL for a library is within 35-40dB, where the external noise from the front and back façade did not reach the optimum range. Therefore, the calculated result suggested that there should be more acoustic absorption strategy to maintain the interior environment of the library, instead of using just acoustic panels, perforated concrete panels on both of the façade to reduce penetration of external noise. And planting of trees and the fountain design at the lowerground floor cretes amsking sound which could reduce occupants focus on the external noise.

REFERENCES

1. Long, M. (2006). Architectural Acoustic. Amsterdam: Elsevier/Academic Pres.

2. Kayelaby.npl.co.uk. (2014). Building Acoustic 2.4.4. Retrieved from http://www.kayelaby.npl.co.uk/general_physics/2_4/2_4_4.html

3. Sae.edu. (2014). Coefficient Chart. Retrieved from http;//www.sae.edu/reference_material/pages/Coefficient%20Chart.ht m

4. Stein, Benjamin & Reynold, John S2000. Mechanical and Engineering Equipment for Buildings. New York.