SCHOOL OF ARCHITECTURE, BUILDING AND DESIGN (SABD)
Bachelor of Science (Hons) in Architecture
BUILDING SCIENCE 2 [BLD 61303] Project 2:
INTEGRATION PROJECT J A L A N TA R C O M M U N I T Y L I B R A R Y
NAME STUDENT ID LECTURER
: Chan Yi Qin : 0315964 : Mr. Azim
TABLE OF CONTENTS 1.0 Introduction
3
2.0 Lighting 2.1 Natural Daylighting 2.1.1 Space 1: Exhibition Gallery
4-7
2.1.2 Space 2: Multimedia and Internet Resources
8-11
2.2 Artificial Lighting + PSALI 2.2.1 Space 1: Foyer
12-16
2.2.2 Space 2: Cafe
17-21
3.0 Acoustic 3.1 External Noise Calculation
22-23
3.1.1 Space 1: Self Study Area
24-27
3.1.2 Space 2: Admin & Support (Office)
28-31
3.2 Reverberation Time 3.2.1 Space 1: Performance Theater
32-33
3.2.2 Space 2: Cafe
34-35
3.3 Transmission Loss 3.3.1 Space 1: Self Study Area
36-38
3.3.2 Space 2: Audio Library
39-41
4.0 References
42
2
1.0 INTRODUCTION As part of the Design Studio 5 integrated module, this project is to focus on the principles of lighting and acoustics in the context of the overall design proposal. With a given urban infill site at Jalan Tuanku Abdul Rahman (TAR), whereby the proposed building will be an intermediate shop lot, sandwiched by 2 other shop lots. Along with a few aordable living spaces, the new proposed building is going to be built as a Community Library. The biggest challenge of the site is the challenge of bringing more natural lighting into the interior space of the building as there are only front, rear facades and a roof contacted to the exterior. Besides that, traďŹƒc induced noise from the front of the site also poses as an issue which needs to be resolved. Last but not least, these materials and products are detailed n order to bring forth an aesthetic, eective and economical outcome. While the Community Library is designed to be human centric, it must be able to provide the best thermal comfort at an economical rate, while also allowing for a quiet place to catch a read and run community meetings. The end outcome is to create a vibrant and interesting place for the community, while welcoming individuals of all ages and all foundations. This will be a centre for an assortment of social, learning and recreational opportunities.
3
2.0 LIGHTING 2.1 Natural Daylighting 2.1.1 Space 1: Exhibition Gallery
A
EXHIBITION GALLERY
A
Ground Floor Plan
EXHIBITION GALLERY
Section A-A
4
Daylight Factor Calculation Zone
DF (%)
Distribution
Very Bright
>6
Very large with thermal and glare problem
Bright
3-6
Good
Average
1-3
Fair
Dark
0-1
Poor
NOTE. The figures are average daylight factors for windows without glazing. Table 1: Daylight Factors and Distribution (Department of Standards Malaysia, 2007)
Formula
Daylight Factor (DF) = (Ei / Eo) x 100%
Area of Space (m2)
85.89
Area of Skylight (m2)
0
Area of Penetration (m2)
10.60 (W) x 3.70 (H) = 39.22 [(Exposed Area + Area of Skylight) / Floor Area] x 100%
Daylighting Factor, DF (%)
= [(39.22 + 0) / 85.89] x 100% = 0.457 x 100% = 4.57% Table 2: Space 1 Daylight Factor Calculation
Conclusion The open exhibition gallery has a daylight factor of 4.57%. Based on the requirements of MS1525 (Table 1), this space is considered as bright zone with good natural daylighting as it is within the range of 3-6%. This space is well shaded by the first floor slab because it is located at the center of the library ground level. Therefore, it receives appropriate natural daylighting during the day.
5
Natural Illumination Calculation Illuminance
Example
120,000 lux
Brightest sunlight
110,000 lux
Bright sunlight
20,000 lux
Shade illuminated by entire clear blue sky, Midday
1,000 - 2,000 lux
Typical overcast day, Midday
< 200 lux
Extreme of darkest storm clouds, Midday
400 lux
Sunrise of sunset on a clear day (Ambient illumination)
40 lux
Fully overcast, Sunset or sunrise
< 1 lux
Extreme of darkest storm clouds, Sunrise or sunset
Task
Illuminance (Lux)
Example of Application
20 100 100 100 100 Lighting for infrequently 150 used area 100 100
Minimum service illuminance Interior walkway and carpark Hotel bedroom Lift interior Corridor, passageway, stairs Escalator, travelator Entrance and exit Staff changing room, locker and cleaner room Entrance hall, lobbies, waiting room Inquiry desk Gate house
100 300 200 200 300-400
Lighting for working interiors
Localized lighting for exacting task
300-400 150 200 150-300 150 150 100 100 300-500 200-750
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
300
Museum and gallery
500 1,000 2,000
Proof reading Exacting drawing Detailed and precise work
Table 3: Recommended Average Illuminance Levels
6
Formula
DF = (E internal, Ei / external, Eo) x 100%
Given, Eo (Unobstructed sky of Malaysia)
20,000 lux
Daylight Factor, DF (%)
45.66 DF = (E internal, Ei / external, Eo) x 100% 45.66 = (Ei / 20,000) x 100%
Natural Illumination Calculation (lux) Ei = (45.66 x 20,000) / 100% = 9132.6 lux Table 4: Space 1 Natural Illumination Calculation
Conclusion According to the standard requirement in MS1525 (Table 3), the general illuminance level of a gallery is 300 lux. The illumination level in this open gallery space is 9132.6 lux which is exceedingly higher than the recommended level. Hence, problems such as thermal discomfort and glare may occur during specific hour of the day. Therefore, there is a need for shading device or double glazed low E-value glass for curtain walls. Besides, interior courtyard is proposed to be placed at the center of ground level. With its natural ventilation, a courtyard helps the library stay appropriately cool. During the day, a courtyard can bring down the buildingâ&#x20AC;&#x2122;s temperature and provide proper shade for the users.
7
2.1.2 Space 2: Multimedia and Internet Resources (Computer Lab)
A
A
MULTIMEDIA & INTERNET
Level 4 Plan
MULTIMEDIA & INTERNET
Section A-A
8
Daylight Factor Calculation Zone
DF (%)
Distribution
Very Bright
>6
Very large with thermal and glare problem
Bright
3-6
Good
Average
1-3
Fair
Dark
0-1
Poor
NOTE. The figures are average daylight factors for windows without glazing. Table 5: Daylight Factors and Distribution (Department of Standards Malaysia, 2007)
Formula
Daylight Factor (DF) = (Ei / Eo) x 100%
Area of Space (m2)
29.31
Area of Skylight (m2)
0
Area of Penetration (m2)
3.99 (W) x 3.20 (H) = 12.77 [(Exposed Area + Area of Skylight) / Floor Area] x 100%
Daylighting Factor, DF (%)
= [(12.77 + 0) / 29.31] x 100% = 0.436 x 100% = 4.36% Table 6: Space 1 Daylight Factor Calculation
Conclusion The computer lab has a daylight factor of 4.36%. Based on the requirements of MS1525 (Table 5), this space is considered as bright zone with a good natural daylighting as it is within the range of 3-6%. This space is well shaded by the fifth floor slab because it is located at the front of level 4. Hence, occupants can use computers in the space comfortably without having too much glares and thermal discomfort problems.
9
Natural Illumination Calculation Illuminance
Example
120,000 lux
Brightest sunlight
110,000 lux
Bright sunlight
20,000 lux
Shade illuminated by entire clear blue sky, Midday
1,000 - 2,000 lux
Typical overcast day, Midday
< 200 lux
Extreme of darkest storm clouds, Midday
400 lux
Sunrise of sunset on a clear day (Ambient illumination)
40 lux
Fully overcast, Sunset or sunrise
< 1 lux
Extreme of darkest storm clouds, Sunrise or sunset
Task
Illuminance (Lux)
20 100 100 100 100 Lighting for infrequently 150 used area 100 100 100 300 200
Lighting for working interiors
Localized lighting for exacting task
Example of Application Minimum service illuminance Interior walkway and carpark Hotel bedroom Lift interior Corridor, passageway, stairs Escalator, travelator Entrance and exit Staff changing room, locker and cleaner room Entrance hall, lobbies, waiting room Inquiry desk Gate house
200
Infrequent reading and writing
300-400
General offices, shops, and stores, reading, and writing
300-400 150 200 150-300 150 150 100 100 300-500 200-750 300
Drawing office Restroom Restaurant, canteen, cafeteria Kitchen Lounge Bathroom Toilet Bedroom Classroom, library Shop, supermarket, department store Museum and gallery
500 1,000 2,000
Proof reading Exacting drawing Detailed and precise work
Table 7: Recommended Average Illuminance Levels
10
Formula
DF = (E internal, Ei / external, Eo) x 100%
Given, Eo (Unobstructed sky of Malaysia)
20,000 lux
Daylight Factor, DF (%)
43.57 DF = (E internal, Ei / external, Eo) x 100% 43.57 = (Ei / 20,000) x 100%
Natural Illumination Calculation (lux) Ei = (43.57 x 20,000) / 100% = 8713.7 lux Table 8: Space 1 Natural Illumination Calculation
Conclusion According to the standard requirement in MS1525 (Table ), the general illuminance level of a computer lab is 300-400 lux. The illumination level in this computer lab space is 8713.7 lux which is exceedingly higher than the recommended level. This proves that the computer lab itself is receiving too much daylight during the day time. Thus, few solutions must be taken in order to counter the issue mentioned such as installing shading devices or double glazed low E-value glass for curtain walls.
11
2.2 Artificial Lighting + PSALI 2.2.1 Space 1: Foyer
FOYER
A
A
Ground Floor Plan
FOYER
Section A-A
12
Foyer is the space connects the entrance to various other spaces upstairs. Foyer functions as the boundary between the outside world and library. That being said, the aid from artificial light is needed to provide suďŹ&#x192;cient amount of illuminance, especially when the day turns into night. Artificial light is important in order to deliver a welcoming ambience when the users enter the library and can be used to complement the area where the natural light is not suďŹ&#x192;cient. Philips Corepro LED Lamp is chosen to light up this space. Lighting Schedule Philips Corepro LED Lamp E27 6W (40W)
Type of Fixture
Vertical Lone Light Fixture
Type of Light
Fluorescent Light
Type of Light Bulb Used
LED Bulb
Lighting Function
Task Lighting
Type of Luminaries
Warm White
Power, W
15W
Voltage, V
230V
Luminous Flux, Im
1142 Im
Color Temperature, K
3000K
Color Rendering Index, CRI
100
Average Life (at 2.7 hrs/day)
15.2 years
Lifetime of Lamp (hrs)
15000 hrs
Lumen Maintenance Factor
0.7
Features
Ernest without glare and harsh shadows
13
Table 9: Utilization Factors (UF) (Source: Lecture Notes)
Lumen Method Calculation Location
Foyer
Dimension (m)
Length (L) = 5.75m Width (W) = 5.77m Height of ceiling = 3.70m
Total Floor Area, A (m2)
5.75 x 5.77 = 33.18
Standard Illuminance Required (lux) according to MS1525, E
150
Lumen of lighting fixtures, Im
1142
Height of luminaire (m)
3.0
Work level (m)
0.8
Mounting Height, Hm (m)
2.4
Assumption of Reflective Value
Ceiling: 0.7 Wall: 0.5 Floor: 0.2
14
Location
Foyer K=
Room Index, RI (K)
L xW (L + W )Hm
5.75x 5.77 (5.75 + 5.77)2.4
=
= 1.20 Utilization Factor, UF
0.6 (Refer to Table 5)
Maintenance Factor, MF
0.7 N=
Lumen Calculation, N
=
Ex A F xUF x MF
150x 33.18 1142x 0.6x 0.7
= 10.38 bulbs ≈11 LxN W = Number of luminaries across
5.75x11 5.77
= 3.31 ≈ 4 Therefore, each spacing would be 5.75 ÷ 4 = 1.44m Wx N L =
Number of luminaries along
5.77x11 5.75
= 3.32 ≈ 4 Therefore, each spacing would be 5.77 ÷ 4 = 1.44m
Table 10: Space 1 Lumen Method Calculation
15
PSALI & Light Fittings Layout
Conclusion 11 fluorescent lamps are used to achieve minimum of 150 lux for this space that stated in MS1525. With the suďŹ&#x192;cient level of illumination, the users will experience comfort, safety and happiness while they first enter the library. First impressions make a big impact, the users can only relax themselves and enjoy the time they spend in other spaces of the library when they feel safe in the environment. Besides, when the day turns into night, this foyer is the only building shines along the street. This makes foyer lighting an integral factor in the overall impression visitors will have of the entire library. Lastly, switch is located near the front desk at main entrance due to the reason it is more convenient for the workers to switch it on or oďŹ&#x20AC; before or after working hours.
16
2.2.2. Space 2: Cafe
A
A CAFE
Ground Floor Plan
CAFE
Section A-A
17
This book cafe is a space where users are able to refuel themselves while getting lost in the city of books. The cafe is located at the ground floor facing the back lane where the back lane has a drop oďŹ&#x20AC; point to east the visitors entering the building. Hence, artificial lighting is importance in order to provide visitors a comfortable and inviting illuminance when they step into the library through the cafe. Besides, since the daylight can hardly penetrate to the back of the library space, Philips LuxSpace Recessed Low Light is chosen to lit up the space. Type of Luminaire Used Philips LuxSpace Recessed Low Light, DN571B
Type of Fixture
Recessed Downlight
Type of Light
Fluorescent Light
Type of Light Bulb Used
LED Bulb
Lighting Function
Task Lighting
Type of Luminaries
Warm White
Power, W
36W
Voltage, V
240V
Luminous Flux, Im
2200Im
Color Temperature, K
4000K
Color Rendering Index, CRI
100
Lifetime of Lamp (hrs)
70000 hrs
Lumen Maintenance Factor
0.7
Features
Ernest without glare and harsh shadows
18
Lumen Method Calculation Location
Cafe
Dimension (m)
Length (L) = 5.92m Width (W) = 5.51m Height of ceiling = 3.70m
Total Floor Area, A (m2)
5.92 x 5.51 = 32.62
Standard Illuminance Required (lux) according to MS1525, E
150
Lumen of lighting fixtures, Im
2200
Height of luminaire (m)
3.5
Work level (m)
0.8
Mounting Height, Hm (m)
2.7
Assumption of Reflective Value
Ceiling: 0.7 Wall: 0.5 Floor: 0.1 K=
Room Index, RI (K)
L xW (L + W )Hm
5.92x 5.51 (5.92 + 5.51)2.7
=
= 1.06 Utilization Factor, UF
0.6 (Refer to Table 5)
Maintenance Factor, MF
0.8 N=
Lumen Calculation, N
=
Ex A F xUF x MF
150x 32.62 2200x 0.6x 0.8
= 4.63 bulbs ≈ 5 LxN W = Number of luminaries across
5.92x 5 5.51
= 2.32 ≈ 3 Therefore, each spacing would be 5.92 ÷ 3 = 1.97m
19
Location
Cafe Wx N L =
Number of luminaries along
5.51x 5 5.92
= 2.16 â&#x2030;&#x2C6; 3 Therefore, each spacing would be 5.51 á 3 = 1.84m
Table 11: Space 2 Lumen Method Calculation
20
PSALI & Light Fittings Layout
Conclusion The cafe has 5 recessed downlight as required. However, lights have to be switched on most of the time for indoor activity to fulfill the requirement of MS1525. In short, this book cafe draws in people who come in for coffee, but stay to read a book. It allows many opportunities for community connection. With sufficient level of illumination, it is able to increase the pleasant and peaceful ambience when visitors enter the space. Users get to drink and savor freshly make organic tea and in house-roasted coffee comfortably, while browse themselves in any of the books, magazines and newspapers available there. Besides, switch is located near to the main entrance due to the reason that it is more convenient for the workers to switch it on or off before and after working hours. 21
3.0 ACOUSTIC 3.1 External Noise (Sound Pressure Level) Given the site is facing towards the main road of Jalan Tuanku Abdul Rahman (TAR), most of the outdoor noise source is hence contributed by vehicular traffic along this route, gradually increasing during peak traffic hours. In addition, very minimal outdoor noise can be heard from the back due to the fact that people or vehicles rarely pass by the back lane. Since the site was give to be an urban infill site, whereby the proposed building will be an intermediate shoplift sandwiched by 2 other shop lots, there will be some activity noise coming from the five-foot walkway, too. Assuming the external noises, Sources of Noise
Sound Pressure Level, SPL(dB)
Traffic noise
80 dB
Activity noise from five-foot walkway
60 dB
Back lane noise
50 dB
Formula, L = 10log10 ( I / Io) Intensity
Calculation 70 = 10 log10
Traffic Noise
Itra f f ic Io
AntiLog 7.0 =
Itra f f ic
1x10−12
Itra f f ic = (107 )(1x10−12 ) Itra f f ic = 1x10−5 60 = 10 log10 Activity Noise
Iactivit y
AntiLog 7.0 =
Io
Iactivit y
1x10−12
Iactivit y = (106 )(1x10−12 ) Iactivit y = 1x10−6
22
50 = 10 log10
Ibacklane Io
AntiLog 5.0 =
Back Lane Noise
Ibacklane 1x10−12
Ibacklane = (10 5)(1x10−12 ) Ibacklane = 1x10−7 Total Intensity, Itotal = Itra f f ic + Iactivit y + Ibacklane = (1x10−5) + (1x10−6 ) + (1x10−7 ) = 1x10−18 Combined SPL = 10 log10 = 10 log
Itotal Io
= 10 log10
p2 , where po = 1x10−12 po 2
1x10−18 [ 1x10−12 ]
= 60 dB
Conclusion The external noise with a combined SPL of 60 dB generated from traffic noise, street activity noises and noises from back lane travels into the library compound without passing through walls that will cause transmission loss. Therefore, the combined SPL of the external noise is approximately the total sound pressure level in the library. The required sound pressure level for a library is 35 dB but the sound pressure level calculated has highly exceeded at 60 dB. Appropriate and necessary actions have to be taken to reduce the sound pressure level into the library.
23
3.1.1 Space 1: Self Study Area
A
A
SELF STUDY AREA
Level 5 Plan
SELF STUDY AREA
Section A-A
24
Sound Pressure Level Calculation: Peak Hour Power Addition Calculation Formula: L = 10 log10 Highest Reading = 65 dB 65 = 10 log10
Lowest Reading = 59 dB
I Io
AntiLog 6.5 =
I Io
59 = 10 log10
I 1x10−12
I Io
AntiLog 5.9 =
I 1x10−12
I = (106.5)(1x10−12 )
I = (10 5.9 )(1x10−12 )
I = 3.16x10−6
I = 7.94x10−7
Total Intensity, Itotal = (3.16x10−6 ) + (7.94x10−7 ) = 3.95x10−6 Combined SPL = 10 log10 = 10 log
Itotal Io
= 10 log10
p2 , where po = 1x10−12 po 2
3.95x10−6 [ 1x10−12 ]
= 65.95 dB
Rule of Thumb Method Difference between the 2 values
Add to larger SPL
0,1
+3
2,3
+2
4-9
+1
10 or greater
0
When Highest Reading = 65 dB; Lowest Reading = 59 dB, Difference between 2 values = Highest Reading - Lowest Reading = 65 dB - 59 dB = 6 dB (difference) 25
Hence, 65 dB + 59 dB = 66 dB Sound Pressure Level Calculation: Non-Peak Hour Power Addition Calculation Formula: L = 10 log10 Highest Reading = 60 dB 60 = 10 log10
Lowest Reading = 52 dB
I Io
AntiLog 6.0 =
I Io
52 = 10 log10
I 1x10−12
I Io
AntiLog 5.2 =
I 1x10−12
I = (106 )(1x10−12 )
I = (10 5.2 )(1x10−12 )
I = 1x10−6
I = 1.58x10−7
Total Intensity, Itotal = (1.x10−6 ) + (1.58x10−7 ) = 1.16x10−6 Combined SPL = 10 log10 = 10 log
Itotal Io
= 10 log10
p2 , where po = 1x10−12 po 2
1.16x10−6 [ 1x10−12 ]
= 60.64 dB
Rule of Thumb Method Difference between the 2 values
Add to larger SPL
0,1
+3
2,3
+2
4-9
+1
10 or greater
0
When Highest Reading = 65 dB; Lowest Reading = 59 dB, Difference between 2 values = Highest Reading - Lowest Reading 26
= 60 dB - 52 dB = 8 dB (diďŹ&#x20AC;erence) Hence, 60 dB + 52 dB = 61 dB
Table 12: Recommended RC and NC Values for Unoccupied Spaces (Source: Lecture Notes)
Conclusion As a result, the average external sound pressure level for self-study area during peak and non-peak hour are 65.96 dB and 60.64 dB. Besides that, rule of thumb method is used in order to prove the power addition calculation is correct.
27
3.1.2 Space 2: Admin & Support (Oï¬&#x192;ce)
A
A
ADMIN & SUPPORT
Level 4 Plan
ADMIN & SUPPORT
Section A-A
28
Sound Pressure Level Calculation: Peak Hour Power Addition Calculation Formula: L = 10 log10 Highest Reading = 66 dB 67 = 10 log10
Lowest Reading = 63 dB
I Io
AntiLog 6.7 =
I Io
64 = 10 log10
I 1x10−12
I Io
AntiLog 6.4 =
I 1x10−12
I = (106.7 )(1x10−12 )
I = (106.4 )(1x10−12 )
I = 5x10−6
I = 2.51x10−6
Total Intensity, Itotal = (5x10−6 ) + (2.51x10−6 ) = 7.51x10−6 Combined SPL = 10 log10 = 10 log
Itotal Io
= 10 log10
p2 , where po = 1x10−12 po 2
7.51x10−6 [ 1x10−12 ]
= 68.76 dB
Rule of Thumb Method Difference between the 2 values
Add to larger SPL
0,1
+3
2,3
+2
4-9
+1
10 or greater
0
When Highest Reading = 66 dB; Lowest Reading = 63 dB, Difference between 2 values = Highest Reading - Lowest Reading = 66 dB - 63 dB
29
= 3 dB (difference) Hence, 66 dB + 63 dB = 68 dB Sound Pressure Level Calculation: Non-Peak Hour Power Addition Calculation Formula: L = 10 log10 Highest Reading = 51 dB 50 = 10 log10
Lowest Reading = 45 dB
I Io
AntiLog 5.0 =
I Io
45 = 10 log10
I 1x10−12
I Io
AntiLog 4.5 =
I 1x10−12
I = (10 5)(1x10−12 )
I = (10 4.5)(1x10−12 )
I = 1x10−7
I = 3.16x10−8
Total Intensity, Itotal = (1x10−7 ) + (3.16x10−8) = 1.32x10−7 Combined SPL = 10 log10 = 10 log
Itotal Io
= 10 log10
p2 , where po = 1x10−12 po 2
1.32x10−7 [ 1x10−12 ]
= 51.21 dB
Rule of Thumb Method Difference between the 2 values
Add to larger SPL
0,1
+3
2,3
+2
4-9
+1
10 or greater
0
30
When Highest Reading = 51 dB; Lowest Reading = 45 dB, Difference between 2 values = Highest Reading - Lowest Reading = 51 dB - 45 dB = 6 dB (difference) Hence, 51 dB + 45 dB = 52 dB Conclusion As a result, the average external sound pressure level for administration office during peak and non-peak hour are 68.76 dB and 51.21 dB. The drastic change of sound level occurs in the office due to the amount of people occupying the space. Besides that, rule of thumb method is used in order to prove the power addition calculation is correct.
31
3.2 Reverberation Time, RT
Table 13: Typical Reverberation Times of Spaces (Source: Lecture Notes)
3.2.1 Space 1: Performance Theater
PERFORMANCE THEATER
Level 4 Plan
32
Reverberation time is deliberated to define the space quality in relation to human comfort. The space performance theater is chosen due to the reason that different types of events, such as conferences, film screening and story sharing sessions, or even operas can be held here, thus an optimum acoustic surrounding must be provided. Reverberation Time Calculation Room Height
6.4m
Standard Reverberation Time for Theaters
0.7 to 1.0s
Volume of Theater, (m3)
(5.92m x 5.51m) x 6.4m = 209.82m 3
Surface Area, m 2
Absorption Coefficient, α (sabin)
Sound Absorption, Sa (m 2sabin)
Pane Glass
23.50
0.04
0.94
Plaster Board
94.48
0.15
14.17
Hung Curtain, Heavy
33.06
0.55
18.18
Rockwool Foam
94.48
0.90
85.03
Floor
Carpet, Heavy, on Reinforced Concrete
32.62
0.14
4.57
Ceiling
Reinforced Concrete
32.62
0.02
0.65
Door
Plywood
28.35
0.06
1.70
Seat
Timber Padded Retractable Tip-up Seat
37.88
0.15
5.68
Component
Wall
Material
Total Absorption, AT (m 2sabin)
130.92
Table 14: Total room surface absorption
Formula: Reverberation Time, RT =
0.16V 0.16x 209.82m 3 = 0.256s ≈ 0.3s = AT 130.92m 2 sa bin
Conclusion The reverberation time for this performance theater is 0.3s. According to the standards of reverberation time, the ideal reverberation time for theaters is between 0.7 to 1.0s. Hence, the reverberation time of the proposed theater design is lower than the optimum reverberation time. To increase reverberation time, one could increase the volume of the room, or reduce the amount of absorption in the room. 33
3.2.2 Space 2: Cafe
CAFE
Ground Floor Plan Implementing sound absorption strategies on cafe can be tricky. Properly done, it will improve speech intelligibility and clarity; too much and space seems dead; too little and patrons complain. DiďŹ&#x20AC;erent people perceive diďŹ&#x20AC;erent noise levels in their own ways. But since this is a library dedicated for young people, and young people tend to gravitate towards environments that are louder and livelier, a vibrant (but not extremely noisy) surrounding must be provided. Reverberation Time Calculation Room Height
3.7m
Standard Reverberation Time for Cafes
0.7 to 0.8s
Peak Hour Capacity
20 people
Volume of Cafe, (m3)
(5.92m x 5.51m) x 3.7m = 120.69m 3
34
Surface Area, m 2
Absorption Coefficient, Îą (sabin)
Sound Absorption, Sa (m 2sabin)
Pane Glass
70.53
0.04
2.82
Plaster Board
75.77
0.15
11.37
Floor
Reinforced Concrete
32.62
0.14
4.57
Ceiling
Reinforced Concrete
32.62
0.02
0.65
Door
Pane Glass
28.35
0.04
1.13
Table
Timber
20.5
0.2
4.10
0.98 (per pcs)
0.28 (per seat)
0.27
Component
Material
Wall
Chair (20pcs) Fabric
Total Absorption, AT (m 2sabin)
24.91
Table 15: Total room surface absorption
Formula: Reverberation Time, RT =
0.16x120.69m 3 0.16V = 0.78s â&#x2030;&#x2C6; 0.8s = 24.91m 2 sa bin AT
Conclusion The reverberation time for the book cafe during peak hours is 0.8s. According to the standards of reverberation time, the ideal reverberation time for cafes is between 0.7 to 0.8s. Hence, the reverberation time of the proposed cafe design on 2000Hz is within the optimum reverberation time.
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3.3 Sound Transmission Loss Formula: T L = 10 log
Tav =
1 Tav
(T 1x A1) + (T 2x A2) + (T 3x A3) + . . . (T n x A n) Total Sur fa ce Ar ea
Tcn = The transmission coeďŹ&#x192;cient of material Sn = The surface area of the material
3.3.1 Space 1: Self Study Area
TERRACE
SELF STUDY AREA
Level 5 Plan This self study area is located on the fifth floor at the middle part of the library. There is an open terrace opposite where it may bring a lot of noise to the audio library. Hence, transmission loss from terrace to audio library should be minimal.
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Components
Materials
Transmission Coefficient, T
Area (m 2)
Sound Reduction Index (SRI)
Curtain wall
Glass
3.16x10−4
35.1
35
Door
Glass
3.16x10−4
8.1
35
Wall
Concrete
6.31x10−5
22.88
42
Transmission Coefficient of Materials Curtain Wall and Glass Door
SRI (glass) = 10 log
35 = 10 log
( Tglass ) 1
( Tglass )
AntiLog 3.5 =
1
Wall
SRI (concrete) = 10 log
42 = 10 log
1
Average Transmission Coefficient of Materials S1TC + S 2TC 2...SnTCn
Total
Sur fa ce
Ar ea
−4 −4 −5 (3.16x10 ) + (3.16x10 ) + (6.31x10 ) Tav = 35.1 + 8.1 + 22.88
Tav = 6.951x10−4 Total Sound Reduction Index, SRI SRI = 10 log10
1
1
Tconcrete
Tconcrete = 6.31 x10−5
Tconcrete = 3.16 x10−4
Tav =
( Tconcrete )
AntiLog 4.2 =
Tglass
1 ( Tav )
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( Tconcrete ) 1
SRI = 10 log10
1 ( 6.951x10â&#x2C6;&#x2019;4 )
SRI = 32 dB Noise Level in Self Study Area = 65 dB - 32 dB = 33 dB Conclusion The overall transmission loss from open terrace is 32dB. Assume that the sound pressure level in the open terrace area is 32dB, the sound that is transmitted through the wall and curtain walls into the self study area is 33dB. According to the noise criteria environment perception, 33dB is below soft whisper noise which is considered as quiet range. It is considered as an ideal value for the self study area as it is a place for study and reading zone without noise disturbance from the open terrace.
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3.3.1 Space 2: Audio Library
READING AREA
AUDIO LIBRARY
Level 3 Plan
This audio library is located at front part of Level 3. It is a space showcases rich collections of music, e-books, audio books, and movies. CDs, DVDs/Blue-Rays are available for check-out. All of the tracks from CD archives totaling more than 10,000 albums are freely sampled at seated stations, where users can browse themselves in the music city while enjoying a cup of coffee bought from the cafe downstairs. The noise control of the entire area shall thus be controlled in order to preserve the peaceful and relaxing ambience.
Components
Materials
Transmission Coefficient, T
Area
(m 2)
Sound Reduction Index (SRI)
Window
Glass
3.16x10−4
0.96
35
Door
Glass
3.16x10−4
3.99
31
Wall
Concrete
6.31x10−5
17.05
42
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Transmission Coefficient of Materials Window
Door
( Tglass ) 1
SRI (glass) = 10 log
35 = 10 log
( Tglass )
AntiLog 3.5 =
SRI (concrete) = 10 log
31 = 10 log
1
1
( Tconcrete ) 1
AntiLog 3.1 =
−4
Tconcrete = 3.16 x10
SRI (concrete) =
( Tconcrete )
1
Tglass
Tconcrete = 7.94 x10−4
S1TC + S 2TC 2...SnTCn
Total
Sur fa ce
1
Tconcrete
Average Transmission Coefficient of Materials Tav =
Wall
Ar ea
−4 −4 −5 (3.16x10 ) + (7.94x10 ) + (6.31x10 ) Tav = 0.96 + 3.99 + 17.05
Tav = 5.332x10−5 Total Sound Reduction Index, SRI SRI = 10 log10
1 ( Tav )
SRI = 10 log10
1 ( 5.332x10−4 )
SRI = 43 dB Noise Level in Audio Library = 55 dB - 43 dB = 12 dB 40
10 log
( Tconcrete )
42 = 10 log
1
( Tconcrete )
AntiLog 4.2 =
1
1
Tconcrete
Tconcrete = 6.31 x10−5
Conclusion The overall transmission loss from hallway to audio library is 43dB. Assume that the sound pressure level in the hallway is 55dB, the sound that is transmitted through the walls into the audio library is approximately 12dB. According to the noise criteria environment perception, 12dB is below the whisper noise. Hence, it is an ideal value for the audio library as users can browse themselves in the music city comfortably without noise disturbance from other spaces.
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4.0 REFERENCES Chan, E. (2017) Room Acoustic Sources. Lecture, Taylor’s Lakeside. Grondzik, W. T., & Kwok, A. G. (2015). Mechanical and electrical equipment for buildings (12th ed.). Hoboken, NJ: Wiley. Moore, J. (1961). Design for Good Acoustics. London : Architectural Press. Schmolked, B. (2011) Theaters and Concert Halls: Construction and Design Manual. Singapore : Page One. Sound of Architecture. (2015) Taking Sound of Architecture. Retrieved 15th July 2017, from http://info.soundofarchitecture.com/blog/recommended-reverberation-times-for-7-keyspaces Sulaiman, A. (2017) Artificial Light Sources. Lecture, Taylor’s Lakeside. Trevor, J., & Peter, D. (2009). Acoustic Absorbers and Diffusers: Theory, Design and Application. London : Taylor & Francis.
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