Building Science II: Acoustic Report

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SCHOOL OF ARCHITECTURE, BUILDING AND DESIGN Bachelor of Science (Hons) in Architecture Building Science 2 (ARC 3413 / BLD61303) Project 1b: Acoustic Performance Evaluation and Design Tutor: Sivaraman Kuppusamy Prepared by: Chen Ee Dong 0321181 Eunice Chan Yu Ming 0315729 Foo Wei Min 0321577 Koh Kar Yi 0320567 Saravanan Vytelingum 0320564 Teo Chen Yi 0320618

Transcript of Building Science II: Acoustic Report

Page 1: Building Science II: Acoustic Report

SCHOOL OF ARCHITECTURE, BUILDING AND DESIGN

Bachelor of Science (Hons) in Architecture

Building Science 2 (ARC 3413 / BLD61303)

Project 1b: Acoustic Performance Evaluation and Design

Tutor: Sivaraman Kuppusamy

Prepared by: Chen Ee Dong 0321181

Eunice Chan Yu Ming 0315729 Foo Wei Min 0321577 Koh Kar Yi 0320567

Saravanan Vytelingum 0320564 Teo Chen Yi 0320618

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CONTENT PAGE

1.0 INTRODUCTION

1.1 Aim and Objective

1.2 Site Information 1.2.1 Site Introduction 1.2.2 Site Selection 1.2.3 Technical Drawings

2.0 PRECEDENT STUDIES

2.1 Introduction 2.2 Acoustic Properties 2.3 Existing Design 2.4 New Design 2.5 Conclusion

3.0 RESEARCH METHODOLOGY

3.1 Acoustic Measuring Equipment 3.2 Methodology 3.3 Data Collection Method 3.4 Limitation 3.5 Zoning

4.0 ANALYSIS

4.1 Zone A (Bar Area)

4.1.1 Locations of Noise Sources 4.1.2 Material and Properties 4.1.3 Sound Meter Reading 4.1.4 Sound Intensity Level (SIL) 4.1.4.1 Peak Period 4.1.4.2 Non-Peak Period 4.1.5 Reverberation Time (RT) 4.1.6 Sound Reduction Index (SRI) 4.1.7 Photographic observation

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4.2 Zone B (Dining Area)

4.2.1 Locations of Noise Sources 4.2.2 Material and Properties 4.2.3 Sound Meter Reading 4.2.4 Sound Intensity Level (SIL) 4.1.4.1 Peak Period 4.1.4.2 Non-Peak Period 4.2.5 Reverberation Time (RT) 4.2.6 Sound Reduction Index (SRI) 4.2.7 Photographic observation

5.0 CONCLUSION

6.0 BIBLIOGRAPHY

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1.0 INTRODUCTION

1.1 Aim and Objective

This project is mainly aimed to help students understand the acoustic characteristics and the requirement in a suggested space. A few calculations will be done to assist the analysis. They are sound intensity level (SIL) which determines sound power per unit area, reverberation time (RT) which is the prolongation of sound as a result of successive reflections and sound reduction index (SRI) which measures the number of decibels lost when transmitted through a partition wall.

1.2 Site Information

1.2.1 Site Introduction

Building proposed is a 8000-square-feet Korean – operated headquarters factory café established by Keith, located in the industrial area at Sunway Damansara. It is a two – storeys building with orange fencing connected with Mayekawa MyCom, renovated from industrial-like warehouse space, hiding from the busy shopping malls in Petaling Jaya. With its modern and contemporary interior hailed from Korea juxtaposing with its factory raw exterior look, Bean Brothers Coffee Malaysia scores significant points and this makes them a hit for all social influencers. In the ground floor are old bricks wall in white that stacks up to towards the high ceiling and numbers of slender dark steel pillars, giving a raw and rustic feel to the environment. Bar counter in the center of the café below the void allow costumer at 1 st floor to overlook barista at work whereas the wooden as well as barrel ‘table’ go around the 360 degree area to cater crowds during peak hour.

Building Identification: Cuisine Café

Location: Jalan PJU 3/50, Sunway Damansara Petaling Jaya Selangor

Opening Hours: 9AM – 8PM

Figure 1.1: Photograph showing exterior view of the

site. (Source: Malaysian Flavor, 2015)

Figure 1.2: Photograph showing interior view of

the site. (Source: Malaysian Flavor, 2015)

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1.2.2 Site Selection

One of the reason why this place is chosen is that it is an extremely spacious coffee bar that scores significant points with various photogenic corners, mainly contributed by the lighting design, the primary element in Architecture Design. In addition, it stands out from the other coffee bar due to its location and context at industrial area. With this given opportunity, we would like to evaluate this social-media-famous café and understand the impact of building design and material on acoustic qualities. Evaluation will be carried out to understand how the acoustic quality can be achieved in its open interior finished by various building materials such as concrete and steel frame and how it is affected by the open kitchen and bar area.

1.2.3 Technical Drawings

Figure 1.3: Ground Floor Plan. (Source:

Keith. 2016)

Figure 1.4: First Floor Plan.

(Source: Keith. 2016)

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2.0 PRECEDENT STUDIES

Case study: The Music Café, August Wilson Center

Location: Pittsburgh, PA, United States

Acoustic: ArupAcoustic

2.1 Introduction

The music café can be accessible directly from the street, it is located at the sidewalk

level from within the center. The area serves as a traditional museum café originally and a

sidewalk café during the day. There is a seating terrace adjacent to the café, designed to lodge

a varied range of emerging technologies with wired internet access, electronic link are provided to all international visitors.

Furthermore, the café is also designed to lodge a series of programs and to perform

as an unconventional performance space for intimate performances with limited seating during the night. A portable stage and theatrical lighting will be imported to support such

performances as required.

Figure 2.1: Photograph showing exterior of Music Café.

(Source: Culture District, n.d.) Figure 2.2: Photograph showing

interior of Music Café. (Source:

Culture District, n.d.)

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2.2 Acoustic Properties

A building design with acoustical design elements is essential. The building has a large

rectangular massing with three glass sides, however, it provides sufficient acoustic properties such as a hard floor, a sound absorbing treatment on the ceiling, hanging metal

baffles and acoustical blanket over 80% of the underside of the floor structure above.

According to the architect, a reverberation time of approximately 1.0 second is ideal as this would place the space somewhere between speech and music use. Architectural

Acoustics: Principles and Design stated: a very high STC value around 60+ would be desirable. This is important to both spaces, as a spoken word performance in the café could

suffer if a huge crowd was gathering in the lobby for a performance in the main theater, while the lobby must remain quiet during a performance in the main theater if patrons are entering or exiting the auditorium since a main set of doors is directly across from the café.

Figure 2.3: Hard Floor. (Source: Pullen, n.d.)

Figure 2.4: Sound Absorbing Treatment.

(Source: AliExpress, n.d.)

Figure 2.5: Hanging Metal Baffles. (Source: Acoustical Surfaces, n.d.)

Figure 2.6: Acoustic Blanket. (Source: All Noise Control, n.d.)

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2.3 Existing Design

Figure 2.7: Music café reflected ceiling plan – Existing Design.

(Source: AE Senior Thesis, n.d.)

REVERBERATION TIME SUMMARY: MUSIC CAFÉ (EXISTING)

Freq (Hz.) 125 250 500 1000 2000 4000

T60 = 1.677 2.596 0.801 0.798 0.807 0.752 Figure 2.8: Music café reverberation time – Existing Design.

(Source: AE Senior Thesis, n.d.)

Figures above prove that the existing reverberation times are far -off from the ideal.

However, the manufacturer of the metal baffle ceiling system has been omitted from the

calculation because it does not have acoustical data for the product. Additional of baffles in the calculation would likely to reduce high reverberation times at lower frequencies and

higher frequencies which are already lower than ideal.

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2.4 New Design

Figure 2.9: Music café reflected ceiling plan – New Design.

(Source: AE Senior Thesis, n.d.)

REVERBERATION TIME SUMMARY: MUSIC CAFÉ (NEW)

Freq (Hz.) 125 250 500 1000 2000 4000 T60 = 1.620 1.243 0.984 1.054 1.077 1.065

Figure 2.10: Music café reverberation time – Existing Design.

(Source: AE Senior Thesis, n.d.)

BAFFLES – MUSIC CAFE

TAG QUANTITY LENGTH (FT)

WIDTH (FT)

PANEL TYPE A

28 8’-0’’ 2’-6’’

PANEL TYPE B

28 3’-6’’ 2’-6’’

Figure 2.11: Music Café New Baffle Schedule of Materials.

(Source: AE Senior Thesis, n.d.)

2.5 Conclusion

The new reverberation times are very close to the desired values. According to

Architectural Acoustics: Principles and Design finest reverberation times at 125 have to be 1.3 times the ideal reverberation time at 500 hertz and a multiplier of 1 .15 should be used at

250 hertz. These multipliers are used to correct for the fact that the human ear is less

sensitive at lower frequencies. With these factors included, the new design is very near the target. The new ceiling system will provide superior acoustical performance at a reduced cost.

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3.0 RESEARCH METHODOLOGY

3.1 Acoustic Measuring Equipment

Figure 3.3: Camera

meter. (Source: REED,

n.d.)

It is used to measure the sound levels at each intersection of gridlines at the site. The readings displayed are in decibel

(dB).

Figure 3.2: Measuring tape.

(Source: REED, n.d.)

It is used to find the intersections of grid line on site for data

recording.

Figure 3.1: Sound level meter.

(Source: REED, n.d.)

It is used to record materials of furniture and building components used.

3.2 Methodology

a) Research on different types of spaces and choose a suitable enclosed space for acoustic study.

b) Obtain approval from the owner and conduct visitation to the chosen site.

c) Measure and sketch the rough building layout before getting the proper plans from the owner.

d) Set gridline at 3m x 3m.

e) Distribute tasks among group members.

f) Collect data based of proper procedure.

g) Observe and record noise sources.

h) Tabulate data.

i) Carry out calculation and analysis.

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3.3 Data Collection Procedure

a) Prepare gridlines of 3m x 3m on the floor plan.

b) Stand at every intersection of gridlines and hold the device at 1m from the ground.

c) Remain silent and record after the reading becomes stable.

d) Record the possible sound source at each intersection point.

e) Repeat step a to d for another period of time (peak/non-peak).

3.4 Limitation

Environmental factor

Due to high sensitivity of sound meter, the reading is very susceptible to

surrounding sound, eg: wind and vehicle.

Human error

Differences in height levels can affect the reading of sound meter. Also, different

manipulators have different height, leading to inaccuracy of result.

3.5 Zonings

Zone A is a bar area. It is near the bar

counter where the baristas brew coffee and where foods are ordered and paid.

It has a total area of 138.39m2 and a total of 20 intersections of gridlines.

Zone B is a spacious area used for dining. There are different types and arrangements of furniture.

It has a total area of 91.11m2 and a total of 12 intersections of gridlines.

Figure 3.4: Plan with zonings.

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4.0 ANALYSIS

4.1 Zone A (Bar Area)

4.1.1 Location of Noise Sources

Figure 4.1: Identification of noise sources found in the building.

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Indication Noise Source Specification Units

Speaker

Product Name Bosch LC2-PC30G6-4 4 Power Handling 50W Frequencies Response

65Hz-20kHz

Input Configuration

70V/100V

Sound Pressure Level

35-45dB

Placement Wall

Air-conditioning

Product Name Daikin FFR15CV1 4 Total Power 940W

Cooling Operation 12500 Btu/hr Sound Pressure Level

38-45 db

Placement Ceiling

Fan

Product Name Panasonic Ceiling Fan PSN-FM15E2

2

Total Power 30W Sound Pressure Level

35-45dB

Placement Ceiling

Electric Appliances

Product Name Mastrena Starbucks Espresso Machine CTS2 801

3

Total Power 800W Sound Pressure Level

82-87

Placement Bar

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4.1.2 Material and Properties

No. Materials Colour Absorption (Hz) Surface 500 2000 4000

1. Clear epoxy floor finishing

Grey 0.01 0.01 0.01 Smooth

2. Concrete wall

Grey 0.01 0.02 0.05 Semi-Smooth

3. Concrete Ceiling

Grey 0.01 0.02 0.05 Semi-Smooth

4. Concrete blocks wall

Light Grey 0.31 0.39 0.25 Rough

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5. Glass

Transparent 0.03 0.02 0.02 Smooth

6. Stainless steel table top

Silver 0.25 0.15 0.15 Smooth

7. Paper drum table (Aluminum top)

Silver 0.4 0.43 0.4 Smooth

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8. Steel stool

Black 0.40 0.43 0.40 Smooth

9. Laminated wood tables and chairs

Light Brown 0.15 0.18 0.20 Semi-Smooth

10. Leather cushion

Black 0.58 0.58 0.50 Smooth

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4.1.3 Sound Meter Reading

Figure 4.4: Plan showing sound meter readings during peak period.

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Figure 4.5: Plan showing sound meter readings during non-peak period.

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4.1.4 Sound Intensity Level (SIL)

4.1.4.1 Peak Period

Highest readings: 75.9, 76.3, 80.7

𝐼𝑡𝑜𝑡𝑎𝑙 = (3.890 x 10−5) + (4.266 x 10−5) + (1.175 x 10−5)

= 9.331 x 10−5

Hence, SIL = 10log ( 𝐼

𝐼𝑜 )

= 10log ( 9.331 𝑥 10 −5

𝐼 𝑥 10−12 )

= 79.70 dB

The sound intensity level at Zone A during peak hour is 79.70dB.

SIL = 10log ( 𝐼𝐴

1𝑜 )

75.9 = 10log ( 𝐼𝐴

1 𝑥 10−12 )

7.59 = log ( 𝐼𝐴

1 𝑥 10−12 )

107.59 = ( 𝐼𝐴

1 𝑥 10−12 )

IA = (1x10−12 ) x (107.59)

= 3.890 x 10−5

SIL = 10log ( 𝐼𝐵

1𝑜 )

76.3 = 10log ( 𝐼𝐵

1 𝑥 10−12 )

7.63 = log ( 𝐼𝐵

1 𝑥 10−12 )

107.63 = ( 𝐼𝐵

1 𝑥 10−12 )

IB = (1x10−12 ) x (107.63)

= 4.266 x 10−5

SIL = 10log ( 𝐼𝐶

1𝑜 )

80.7 = 10log ( 𝐼𝐶

1 𝑥 10−12 )

8.07 = log ( 𝐼𝐶

1 𝑥 10−12 )

108.07 = ( 𝐼𝐶

1 𝑥 10−12 )

IC = (1x10−12 ) x (108.07 )

= 1.175 x 10−5

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4.1.4.2 Non-Peak Period

Highest readings: 66.1, 66.9, 66.8

𝐼𝑡𝑜𝑡𝑎𝑙 = (4.074 x 10−6) + (4.898 x 10−6) + (4.786 x 10−6)

= 1.376 x 10−5

Hence, SIL = 10log ( 𝐼

𝐼𝑜 )

= 10log ( 1.376 𝑥 10−5

𝐼 𝑥 10−12 )

= 71.39 dB

The sound intensity level at Zone A during non-peak hour is 71.39dB.

SIL = 10log ( 𝐼𝐴

1𝑜 )

66.1 = 10log ( 𝐼𝐴

1 𝑥 10−12 )

6.61 = log ( 𝐼𝐴

1 𝑥 10−12 )

106.61 = ( 𝐼𝐴

1 𝑥 10−12 )

IA = (1x10−12 ) x (106.61)

= 4.074 x 10−6

SIL = 10log ( 𝐼𝐵

1𝑜 )

66.9 = 10log ( 𝐼𝐵

1 𝑥 10−12 )

6.69 = log ( 𝐼𝐵

1 𝑥 10−12 )

106.69 = ( 𝐼𝐵

1 𝑥 10−12 )

IB = (1x10−12 ) x (106.69)

= 4.898 x 10−6

SIL = 10log ( 𝐼𝐶

1𝑜 )

66.8 = 10log ( 𝐼𝐶

1 𝑥 10−12 )

6.68 = log ( 𝐼𝐶

1 𝑥 10−12 )

106.68 = ( 𝐼𝐶

1 𝑥 10−12 )

IC = (1x10−12 ) x (106.68 )

= 4.786 x 10−6

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4.1.5 Reverberation Time (RT)

Volume of Zone A = 484.36m3

Material absorption coefficient at 500Hz

Component Material Surface Area (m2)

/ Quantity

Absorption Coefficient

Sound Absorptio

n

Floor Clear epoxy floor finishing 138.39 0.01 1.38 Wall Concrete blocks wall plaster finish 59.37 0.31 18.40

Exposed concrete blocks 44.45 0.25 11.11 Glass 19.50 0.03 0.59

Ceiling Concrete 57.65 0.01 0.58 Furniture Stainless steel table top 2 0.25 0.50

Paper drum table ( Aluminum) 8 0.40 3.20 Steel stool 24 0.40 9.60 Laminated wood tables 2 0.15 0.30

Occupants 25 0.46 11.50 Total Absorption (A) 57.16

RT = 0.16 𝑥 484 .36

57 .16 = 1.36s

Material absorption coefficient at 2000Hz

Component Material Surface Area (m2)

/ Quantity

Absorption Coefficient

Sound Absorption

Floor Clear epoxy floor finishing 138.39 0.01 1.38 Wall Concrete blocks wall plaster finish 59.37 0.39 23.15

Exposed concrete blocks 44.45 0.30 13.34 Glass 19.50 0.02 0.39

Ceiling Concrete 57.65 0.02 1.15 Furniture Stainless steel table top 2 0.15 0.30

Paper drum table ( Aluminum) 8 0.43 3.44 Steel stool 24 0.43 10.32 Laminated wood tables 2 0.18 0.36

Occupants 25 0.51 12.75 Total Absorption (A) 66.58

RT = 0.16 𝑥 484 .36

66 .58 = 1.16s

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4.1.6 Sound Reduction Index (SRI)

There is no separation of quiet zone from the open bar, dining and even kitchen area hence no partition wall can be found in the chosen study area. Therefore, a wall that

separates the open area and store room will be taken as an example to show the calculation for sound reduction index.

Figure 4.6: Elevation of interior wall.

Component Surface Area (m2), S Sound Reduction Index, T

Transmission Coefficient, T= 1/log-1 (T/10)

Concrete Block Wall

25 42 6.310 x 10-5

Wooden Door 2 28 1.585 x 10-3

Tav = (S1T1 + S2T2)/(S1+S2)

= [25(6.310 x 10-5) + 2(1.585 x 10-3)]/(25+2)

= 1.758 x 10-4

Overall SRI = 10 log (1/ 1.758 x 10-4)

= 37.55dB

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4.1.7 Photographic observation

The café is located in Jalan PJU, the corner slot next to the industrial area and adjacent

to residential area, Sunway Rymba Hill, therefore vehicle circulation in front of the site is quite low as the end of the road only consist of high end residence.

Human noises are high in the café especially in zone B due to the fact that it is mostly

tables filled with customers doing activities such as chit-chatting, laughing and etc. Other than that, there are also noises coming from zone B, the baristas’ area, human noise level is solely based on reception activities and customer from café lounge.

Figure 4.7: Mayekawa (M) Sdn Bhd, factory next to Bean Brother.

Figure 4.8: Rymba Hill, adjacent to the Bean

Brother.

Figure: Zone C, social activities happen during peak hour (Source)

Figure 4.9: Zone B, social activities happen during peak hour.

Figure 4.10: Café lounge in front of the barista area.

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Speakers are distributed throughout the building for the purpose of playing soft music during opening hour.

Figure 4.11: Speakers located at the every possible wall throughout the building.

Appliances at the barista such as coffee maker and cooler which generate cool air

to keep cakes and dessert fresh produce noise on its own. Furthermore, noises from the open kitchen which produce by the fiction of appliances also contribute certain amount of turbulence and clearly hearable.

Ceiling Cassette Unit are found

distributed evenly to cover most of the area. They are high in power and produce relatively low noise.

Figure 4.12: Café lounge in front of the barista area.

Figure 4.13: Barista in the middle of the building.

Figure 4.14: Open kitchen.

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4.2 Zone B (Dining Area)

4.2.1 Locations of Noise Sources

Figure 4.15: Identification of noise sources found in the building.

Indication Noise Source Specification Units

Speaker

Product Name Bosch LC2-PC30G6-4 3

Power Handling 50W Frequencies Response

65Hz-20kHz

Input Configuration

70V/100V

Sound Pressure Level

35-45dB

Placement Wall

Air-conditioning

Product Name Daikin FFR15CV1 2 Total Power 940W

Cooling Operation 12500 Btu/hr Sound Pressure Level

38-45 db

Placement Ceiling

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Fan

Product Name Panasonic Ceiling Fan PSN-FM15E2

2

Total Power 155W Sound Pressure Level

35-45dB

Placement Ceiling

4.2.2 Material and Properties

No. Materials Colour Absorption (Hz) Surface 500 2000 4000

1. Clear epoxy floor finishing

Grey 0.01 0.01 0.01 Smooth

2. Concrete wall

Grey 0.01 0.02 0.05 Semi-Smooth

3. Concrete Ceiling

Grey 0.01 0.02 0.05 Semi-Smooth

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4. Concrete blocks wall

Light Grey 0.31 0.39 0.25 Rough

5. Glass

Transparent 0.03 0.02 0.02 Smooth

6. Stainless steel table top

Silver 0.25 0.15 0.15 Smooth

7. Paper drum table (Aluminum top)

Silver 0.4 0.43 0.4 Smooth

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8. Steel stool

Black 0.40 0.43 0.40 Smooth

9. Laminated wood tables and chairs

Light Brown 0.15 0.18 0.20 Semi-Smooth

10. Leather cushion

Black 0.58 0.58 0.50 Smooth

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4.2.2 Sound Meter Reading

Figure 4.16: Plan showing sound meter readings during peak period.

Figure 4.17: Plan showing sound meter readings during non-peak period.

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4.2.3 Sound Intensity Level (SIL)

4.1.3.1 Peak Period

Highest readings: 77.2, 76.0, 76.2

𝐼𝑡𝑜𝑡𝑎𝑙 = (5.248 x 10−5) + (3.981 x 10−5) + (4.169 x 10−5)

= 1.340 x 10−4

Hence, SIL = 10log ( 𝐼

𝐼𝑜 )

= 10log ( 1.340 𝑥 10−4

𝐼 𝑥 10−12 )

= 81.27 dB

The sound intensity level at Zone B during peak hour is 81.27dB.

SIL = 10log ( 𝐼𝐴

1𝑜 )

77.2 = 10log ( 𝐼𝐴

1 𝑥 10−12 )

7.72 = log ( 𝐼𝐴

1 𝑥 10−12 )

107.72 = ( 𝐼𝐴

1 𝑥 10−12 )

IA = (1x10−12 ) x (107.72)

= 5.248 x 10−5

SIL = 10log ( 𝐼𝐵

1𝑜 )

76.0 = 10log ( 𝐼𝐵

1 𝑥 10−12 )

7.60 = log ( 𝐼𝐵

1 𝑥 10−12 )

107.60 = ( 𝐼𝐵

1 𝑥 10−12 )

IB = (1x10−12 ) x (107.60)

= 3.981 x 10−5

SIL = 10log ( 𝐼𝐶

1𝑜 )

76.2 = 10log ( 𝐼𝐶

1 𝑥 10−12 )

7.62 = log ( 𝐼𝐶

1 𝑥 10−12 )

107.62 = ( 𝐼𝐶

1 𝑥 10−12 )

IC = (1x10−12 ) x (107.62 )

= 4.169 x 10−5

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4.1.3.2 Non-Peak Period

Highest readings: 65.3, 66.3, 66.3

𝐼𝑡𝑜𝑡𝑎𝑙 = (3.388 x 10−6) + (4.266 x 10−6) + (4.266 x 10−6)

= 1.192 x 10−5

Hence, SIL = 10log ( 𝐼

𝐼𝑜 )

= 10log ( 1.192 𝑥 10 −5

𝐼 𝑥 10−12 )

= 70.76 dB

The sound intensity level at Zone B during non-peak hour is 70.76dB.

SIL = 10log ( 𝐼𝐴

1𝑜 )

65.3 = 10log ( 𝐼𝐴

1 𝑥 10−12 )

6.53 = log ( 𝐼𝐴

1 𝑥 10−12 )

106.53 = ( 𝐼𝐴

1 𝑥 10−12 )

IA = (1x10−12 ) x (106.53)

= 3.388 x 10−6

SIL = 10log ( 𝐼𝐵

1𝑜 )

77.2 = 10log ( 𝐼𝐵

1 𝑥 10−12 )

7.72 = log ( 𝐼𝐵

1 𝑥 10−12 )

107.72 = ( 𝐼𝐵

1 𝑥 10−12 )

IB = (1x10−12 ) x (107.72)

= 4.266 x 10−6

SIL = 10log ( 𝐼𝐶

1𝑜 )

77.2 = 10log ( 𝐼𝐶

1 𝑥 10−12 )

7.72 = log ( 𝐼𝐶

1 𝑥 10−12 )

107.72 = ( 𝐼𝐶

1 𝑥 10−12 )

IC = (1x10−12 ) x (107.72 )

= 4.266 x 10−6

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4.2.4 Reverberation Time (RT)

Volume of Zone B = 329.38m3

Material absorption coefficient at 500Hz

Component Material Surface Area (m2)

/ Quantity

Absorption Coefficient

Sound Absorption

Floor Clear epoxy floor finishing 94.11 0.01 0.94 Wall Concrete with plaster finish 19.15 0.05 0.96

Concrete blocks wall plaster finish 151.34 0.31 46.92 Exposed concrete blocks 12.32 0.25 3.08 Glass 17.68 0.03 0.53

Ceiling Concrete 89.53 0.01 0.90 Furniture Steel stool 28 0.40 11.20

Laminated wood tables 15 0.15 2.25 Leather cushion 2 0.58 1.16

Occupants 8 0.46 3.68 Total Absorption (A) 71.62

RT = 0.16 𝑥 484 .36

71 .62 = 1.08s

Material absorption coefficient at 2000Hz

Component Material Surface Area (m2)

/ Quantity

Absorption Coefficient

Sound Absorption

Floor Clear epoxy floor finishing 94.11 0.01 0.94 Wall Concrete with plaster finish 19.15 0.09 1.72

Concrete blocks wall plaster finish 151.34 0.39 59.02 Exposed concrete blocks 12.32 0.30 3.70 Glass 17.68 0.02 0.35

Ceiling Concrete 89.53 0.02 1.79 Furniture Steel stool 28 0.43 12.04

Laminated wood tables 15 0.18 2.70 Leather cushion 2 0.58 1.16

Occupants 8 0.46 3.68

Total Absorption (A) 87.10

RT = 0.16 𝑥 484 .36

87 .10 = 0.89s

Page 33: Building Science II: Acoustic Report

4.2.6 Photographic observation

Speakers are distributed throughout the building for the purpose of playing soft music during opening hour.

Figure 4.18: Speakers located throughout the building.

Figure 4.19: Café lounge in front of the barista area.

Fans are found on the area that

are not covered by the air conditioner. Produce certain

amount of noises but noises

often covered by the noises of

human activities and not till extend which will distract and

affect the customers nearby.

Page 34: Building Science II: Acoustic Report

5.0 CONCLUSION

Type of occupancy & activities

Recommended reverberation time

Coffee bars 45 50 <1.0

Restaurant 45 50 <1.0

Recommended design sound level of a coffee bars and restaurants should be in the

average of 45db to 50dB with the recommended time of less than 1.00s by according to AS/ZS 2107:2000 standard for reverberation time and sound levels.

Zones Sound Pressure Level (dB)

Reverberation Time (s) 500Hz

Reverberation Time (s) 2000Hz

A 79.70 dB , 71.39dB 1.36s 1.16s

B 81.27 dB, 70.76dB 1.08s 0.89s

It can be concluded that both two zones did not meet the minimum requirement of

the acoustic standard for 500Hz except for zone B which has less than 1.00s reverberation time for 2000Hz. This is due to the selections of material, material that has been use d cannot

absorb sounds efficiently.

From the table above, it is clear that zone B has the highest sound pressure level during peak hours due to the amount of human activities and noise sources of the

surrounding. Furthermore, open space concept of the café has also led to the high sound pressure level, for instance, due the open ceiling of the ground floor, noises from the first

floor can be transmitted to the ground floor.

Satisfactory

y Satisfactory

Maximum

y

Satisfactory

Page 35: Building Science II: Acoustic Report

6.0 BIBLIOGRAPHY

1. Malaysian Flavor. (2015). Bean Brothers Malaysia @ Sunway Damansara. Retrieved from

http://www.malaysianflavours.com/2015/09/bean-brothers-malaysia-sunway-damansara-pj.html

2. Culture District. (N.d). August Wilson Center. Retrieved from https://culturaldistrict.org/pages/awc

3. Pullen. (N.d). Eco Friendly Wood Floor. Retrieved from http://greenliving.lovetoknow.com/Eco_Friendly_Wood_Floor

4. Reed. (N.d). REED C-322 Sound Level Meter/Data Logger, 32 to 130dB. Retrieved from http://www.reedinstruments.com/product/reed-instruments-c-322-sound-level-meter-

data-logger

5. AliExpress. (N.d). Acoustic Foam. Retrieved from https://www.aliexpress.com/w/wholesale-acoustic-foam.html

6. Acoustical Surfaces (N.d). Echo Eliminator. Retrieved from http://www.acousticalsurfaces.com/echo_eliminator/ee_hangbaf.htm

7. All Sound Control. (N.d). Outdoor Noise Control Blankets. Retrieved from http://www.allnoisecontrol.com/outdoor-noise-control-blankets.cfm

8. AE Senior Thesis. (N.d). – August Wilson Center. Retrieved from

https://www.engr.psu.edu/ae/thesis/portfolios/2008/mpr184/files/final_report/Section5_Acoustics.pdf