building science report

Project 1: Lighting and Acoustic Performance

Evaluation and Design

Brogues Coffee, Subang Jaya

Building Science 2 (ARC 3413)

Tutor: Mr. Siva

Group Members:

Chong Chui Wern 0321359

Ellen Gowiko 0318496

Law Yong Lin 0320516

Liew Hong Zhi 0315836

Nicholas Lee Ngang Kim 0320504

Abstract This report consists of the study of lighting and acoustic performance level of a selected building. The building we have chosen to study is Brogues Coffee, which is a modern café located at SS15, Subang Jaya. In order to carry out the analysis for this project, we asked owner of the café for the floor plan and edited parts of the café which was later changed, such as the furniture positions and positions of doors, so that a more accurate analysis can be conducted. Next, we then visited the café several times after that to ensure the data collected is sufficient for future analysis conducted on the cafe. Light and sound acoustic data are collected at different points all over the café at a distance of 1.5m apart. We analyzed the building components, furniture and the finishing. of both interior and exterior. A list of figures and data collected are used and some references is provided at the end of our report further detailed information. In addition, a lot of photos has been taken as references or evidence of the project studies.

Table of content

Content Pages

1.0 Introduction 1.1 Introduction to project 1.2 Introduction to site 1.3 Zoning

1 - 3

2.0 Lighting 2.1 Introduction to Lighting 2.2 Journal 2.3 Methodology 2.4 Lighting Analysis 2.5 Analysis Diagram 2.6 Conclusion

4 - 44

3.0 Acoustic 3.1 Introduction to Acoustic 3.2 Journal 3.3 Methodology 3.4 Acoustic Analysis 3.5 Analysis Diagram 3.6 Conclusion

45 - 103

4.0 Conclusion 103

Reference 104

1

1.0 Introduction

1.1 Introduction to project Lighting and acoustic performance of a building is one of the key in to making a space liveable and comfortable. When used within the right range, the user experience and comfort can be improved. Furthermore, the manipulation of these elements can help enhance the atmosphere, feelings and mood of the place.

Lightings are important as it is one of the main safety factors to the users of the spaces. Poor lighting may cause psychological issues such as anxiety and further lead to accidents if people cannot make sense of what is ahead of them. The acoustic performance of a building is also important as it controls the transfer of noise from one space to another. The requirements of each spaces may vary according to their users and functions. It helps provide a suitable environment by cancelling out unwanted noise from the outside.

In a group of 5, we are to choose a site to analyse their lighting and acoustic quality. The aim and objectives of this project are:

- To understand the day-lighting, artificial lighting and acoustic characteristic.

- To determine the characteristics and function of day-lighting, artificial lighting, sound and acoustic within the intended space.

- To critically report and analyse the lighting and acoustic qualities in the space.

- To be able to produce a complete documentation on analysis of space in relation to lighting requirement.

Hence, at the end of this project, we should be able to determine and understand the quality of spaces based on the lighting and acoustic quality. We will also be able to understand the various factors affecting the quality of light and acoustic performance. Lastly, we can be clear as of the different requirements for light and acoustic for each individual spaces.

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1.2 Introduction to site

Figure 1.1 Brogues Coffee exterior

Case Study: Brogues Coffee, SS15, Subang Jaya

Building Space: Café

Business Hours: 11AM to 1AM

Brogues coffee cafe is a modern concept cafe which believes in not only serving good coffee to customers but attitude. The serves tarts, cakes and coffee. It is an ideal location to chill, gathering or relaxing, a good ambient for youngster nowadays. This makes the building worth studying or exploring which allow us to understand the effects on lighting and acoustic within the spaces. Moreover, the building which is just right at the corner, sits in between the street, surrounded by crowds and other shop lots. This becomes another issue that we should take note of in this study. We visited the site several times in order to collect all the necessary information and data for this project which includes the measured drawings, lighting and acoustic reading.

3

1.3 Zoning

Figure 1.2 Zoning of the spaces in the cafe

The zoning of the spaces is done based on the function of each spaces.

Purple – Toilet area

Yellow – Dining Zone1

Blue – Dining Zone 2

Red – Kitchen / Work area

Green – Outdoor area

4

2.0 Lighting

5

2.1 Introduction to lighting The relationship between light and architecture is closely related to the principles of physics, about energy and matter. But, light also helps define the architectural space as it contributes to its perception and understanding, at the mean time adding values to the function of spaces and adding an emotional component for its users. Of course, the primary purpose of light is to provide visibility for security and safety of the users.

Lighting play an important role as it achieves a certain level of human comfort. Different spaces do require different type of lighting as to cater to the function of the space and also the user comfort and experience. When the brightness of a space does not meet the requirements compatible to their function, the space is deemed unsuitable to carry out its destined function and purpose.

There are 2 main ways to light up a building, which is through:

1. Daylight (Natural) lighting

Daylighting is the controlled admission of natural sunlight and diffuse skylight into a building or space. Daylighting is a viable, energy-efficient strategy in almost any climate. The daylighting system is designed to bring in natural light in to the building, such that electric lights can be dimmed or turned off when daylighting system is at work.

2. Artificial lightings

Artificial light sources are sources of light which developed to compensate for of or assist the lacking of natural light. Artificial lightings come in different frequencies and wavelengths, which determines the light colour. Indoor lighting is usually accomplished using light fixtures, and is a key part of interior design.

Luminaire is a device that distributes the filters or transforms light emitted from one or more source. The basic physical principles used in optical luminaire are reflection, absorption, transmission and refraction.

Figure 2.1 Natural lighting and artificial lighting (Source: https://www.beautylish.com/a/vcjwj/makeup-lighting-tips)

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2.2 Journal

2.2.1 Introduction

George C. Gordon Library

Figure 2.2 Interior view of George C. Gordon Library (Source: Architecture and Design, 2014)

Building Information:

Name : George C. Gordon Library

Project Completion : 2013

Function : Library

Locations : Worcester Polytechnic Institute,

Worcestershire, England.

Architects : CK Design International

Client : Worcester Polytechnic Institute

Located in Worcester Polytechnic Institute, George C. Gordon Library offers a fine

environment to the students studying in the campus. By enhance the user experience while

at the same time enabling the visibility of the soothing environment of the library’s interior, the

challenge in illuminating this library’s interior lay in the need to introduce functional and iconic

lighting. In order to achieve this, the strategy of the lighting has to be placed wisely over the

library. By designing the lighting systems up to its optimal, this library did a great job because

these systems are adaptive to sunlight as well as the users. George C. Gordon Library has

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given a pleasant, glare-less, working environment for the building users which is a suitable

workspace for students, faculty and staff.

2.2.2 Lighting Analysis

Figure 2.3 Ground floor plan is comprised of Collaborative Work Space (Section 1 and 4), Computer

Work Space (Section 2), and Shelving (Section 3). Unlabeled spaces are the Archives. (Source:

LIGHTING STUDY OF THE GEORGE C. GORDON LIBRARY, 2015)

Referring to figure 2.3, the sunlight can enter to allow optimum natural lighting from the

collaborative workspaces organization. Unlike the computer work space and the shelving

area are located at the inner part of the library to ensure the need of having a mire controlled

lighting environment.

Collaborative Work Space

Figure 2.4 Collaborative space (Section 1) of Gordon Library.

(Source: LIGHTING STUDY OF THE GEORGE C. GORDON LIBRARY, 2015)

Fluorescent light

Tinted windows

Bright coloured walls Dominant Colours:

White and Grey

8

Figure 2.5 Collaborative space (Section 4) of Gordon Library.


In the middle and the east side of the ground floor of the library is where the collaborative

work space is located. Since it is where the students get to do their work and discussion,

lighting is become an important factor. Fluorescent tubes can be found in section 1 whereas

fluorescent bulbs are used along the whole area of section 4, this allow the library to have a

controlled amount of light suitable for the users in the area. The lights are located on the

strategic area on the ceiling of the space which made light can enter directly to the area

where activities were took space. Tinted windows are also used for natural lighting to enter

the collaborative space. The collaborative room uses natural white lights, therefore white and

grey is the dominant colours of the place. Natural white light creates more suitable mood for

reading and studying than warm light which is become a reason of why natural white lights

were used instead of warm lights.

Figure 2.6 Fluorescent Light in the Collaborative space

Tinted windows

Fluorescent bulb

Bright Coloured Walls Dominant Colours:

White and Grey

9

Computer Work Space

Figure 2.7 Computer work space (Section 2) of Gordon Library.


Located at the west side of ground floor, computer work space is the place where

students get to do their work using computer facilities with or without internet. Fluorescent

tubes are the main component that provides lighting in the area. It placed in the place that

can be seen above the areas. As a computer area, it is important that the lighting shouldn’t

be glare-free which is it suitable environment for the users to do their work with computer.

White coloured wall also can be seen around the area which is it giving the area a brighter

mood and at the same time it won’t hurt users eyes easily.

Figure 2.8 Fluorescent Light used in the Computer Work Space

Fluorescent tube

White wall

Dominant Colours:

White and Grey

10

Shelving

Figure 2.9 Shelving area (Section 3) of Gordon Library.


The shelving area for ground floor is located at the north side. The shelving area has a

unique type of lighting control sytem called ‘Infrared Light Censor’. This system is used to

control the amount of light intensity that come from the lights. When the censor senses a high

amount of the light entering the area, it will reduce the light intensity of the lights. Light

intensity must to be control in this area because books here are to be kept in a propere

manner and with high intensity of light, the books will be damage as the time goes.

Figure 2.10 Fluorescent tube light used on the shelving area

Fluorescent tube

Infrared light censor

Dominant Colours:

Brown and Grey

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Ground Floor Lux Measurement

This section describes the lux recommendations and measurements for each of the

sections on the ground floor.

Table 2.1 Lux recommendation for each of the sections on the ground floor

Table 2.2 comparison of measured lux with recommended lux for non-windowed sections on the

ground floor

Table 2.3 comparison of measured lux with recommended lux for the windowed section on the

ground floor

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Figure 2.11 Lux measurements throughtout the day for section 4 on ground floor

Sunlight

Each floor contains windows that let in natural light throughtout the day. The team

compared the length of the windows to the length of the wall to determine what percentage

of the wall was comprised of windows. Table below shows the calculations for the library

window measurements in the library.

Table 2.4 Window Measurements

13

Figure 2.12 An image of the east-facing floor-to-ceiling windows in the library

The team tracked the position of the sun throughtout the day using a compass and an

online sun calculation to determine the windowed sections were affected by outside light.

Figure 2.13 below shows the position of the sun as the day progressed as the sections were

affected by sunlight at certain times of the day.

Figure 2.13 Sun movement

14

This lighting study was completed in early spring, just after the start of the daylight

savings time. At this time of year, the sun rise 48o east of due south, sets 48o west of due

south and will never directly affect the north side of the library. Later in the year, in June and

July, the sun will rise 64o east of due south and set 64o west of due south. The duration time

of the sun affects the library wil increase as spring turns to summer because of long daylight

hours. In the winter, the duration of sunlight will decreases which giving smaller effect sunlight

in the library. Measurements for this lighting study were collected in early April when the sun

illuminated the library for almost thirteen hours a day.

Illumination

The recorded lux measurements were compared to the recommended lux values for each

section. Subsequently, the team calculated the percentage that the measured lux differed

from the recommended lux value. The percentages were divided onto 5 categories:

Very bright : More than 75% above the recommended value

Bright between : 25% and 75% above the recommended value

Appropriately lit : Between ± 25% difference from the recommended value

Dim between : 25% and -75% below the recommended value

Very dim : Less than -75% below the recommended value

Figure 2.14 Percentage difference between recommended lux values and measured lux values on the ground floor of the library

15

The figure above shows the percentage off of recommended illuminance values for all

non-windowed sections of the library (ground floor). A sun symbol represents a section that

is significantly impacted by natural lighting. The windowed sections illumination level

changes according the day and will be discussed later in the project.

Bulb Temperature

The team found that only a relatively small percentage of input power to a bulb is output

as visible light. To assess the input power radiated as heat, the team measured the

temperatures of three household bulbs with the same lux output values: LED bulb, CFl bulb,

and Halogen bulb. The temperature data for the three bulbs are given in Figure 2.15.

Figure 2.15 Temperatures of 800 lumen household bulbs

The figure above shows that halogen bulb and CFL bulb are much hotter than LED bulb.

The difference in temperature between LEDs and older bulb indicate that LED bulb produce

less heat from the bulb’s input power, making LED bulb more efficient than older alternatives.

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2.2.3 Conclusion

The Gordon Library has shown how different lighting control can be used in different

section of the area within a building. Some sections such as the shelving needed a more

specific lighting control to the extent of using infrared light censor while some sections

doesn’t need such a way.

Different kind of lighting are needed in a way for users be able to experience different

lighting design when moving from one space to another which also bring the users to have a

better lighting in different activies. Lighting design plays a very important role in architecture,

because with the correct lighting design, users are allow to do their activities comfortably

and at the same time providing the right mood and ambience to those around the space.

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2.3 Methodology

2.3.1 Preparation

1. Preliminary studies and identification of the spaces that we are choosing were studied before we went to do the case study.

2. Choices of building were suggested for precedent studies to have a better understanding of light functioning would affect in a quality of space.

3. After getting approved for the site as our case study, we made phone calls the shop to have our permissions for our case study.

4. We obtained the plan drawing of the site from the owner of the shop.

5. We differentiated to a few spaces according to different function of the space.

6. We plotted a set of grid lines of 1.5m on the plan for recording later on.

7. Get the lighting data collection device, Digital Lux Meter from our university.

8. Understand how the device works in different conditions and situations before the site visit.

9. Study of basic standard and regulations such as CIBSE, ASHRAE and MS 1525 before that to understand analyzing and comparing the data further on.

2.3.2 Lighting data collection device

2.16 Digital Lux Meter Model LX-101

Lux meters are used to measure the intensity of illumination as distinguished by the human eyes. The value shown does not co-relate to an objective value of energy radiated or reflected. As different wavelengths within the visible spectrum are perceived with varying sensitivity of the eyes, lux meters evaluate light intensity in consideration of the said variable.

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2.3.3 Lighting data collection method

One of our group member prepared the orthographic drawings before we went for the actual data collection day. We get our lighting data measuring device, Digital LUX meter by lending from our university resources. We then went to our site which located in SS15 to start our measuring work. We listed down all the lighting sources that available in site because it may affect our measurements. We set up a grid line of 1.5 meter of intervals for the lighting data collection after discussed with our lecturer. According to our gridlines, we collected our lighting data on every point of the gridlines by placing the device at a height of 1 meter and 1.5 meter as it is for sitting position and eye level position. We recorded the data on different time, which are the evening for the non-peak hour and night for peak hour. We then insert all the lighting data into a table for further analysis.

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2.4 Lighting Analysis

2.4.1 Building components

Figure 2.17 Zoning

Zone 1: Toilet Zone

Figure 2.18 Toilet Zone

20

Floor

Component Details Surface Finish Reflectance Value (%)

Surface Area (m2)

Grey Ceramic

Smooth

Matte

Ceramic Tile

35

4.23

Walls


Surface Area (m2)

A1

Grey Ceramic

Smooth

Matte

Ceramic Tile

35

4.70

A2

Grey Ceramic

Smooth

Matte

Ceramic Tile

35

8.12

A3

Grey Ceramic

Timber Door

Smooth

Matte

Wood

10

Ceramic Tile

35

Wall: 2.76

Door: 1.94

Total: 4.70

21

A4

Grey Ceramic

Smooth

Matte

Ceramic Tile

35

8.12

Ceiling


Surface Area (m2)

Concrete

White Paint

Smooth

White Paint

71

4.23

Zone 2: Dining 1

Figure 2.19 Dining Zone 1

Floor


Surface Area (m2)

Plywood

Matte

Wood

10

11.83

22

Wall


Surface Area (m2)

B1

Brick

Plaster

Beige Paint

Smooth

Beige Paint

63

6.96

B2

Brick

Plaster

Beige Paint

Smooth

Beige Paint

63

15.30

B3

Brick

Plaster

Beige Paint

Smooth

Beige Paint

63

6.96

Ceiling


Surface Area (m2)

Concrete

Black Paint

Smooth

Black Paint

4

11.83

23

Furniture

Component Details Colour Surface Finish Reflectance Value (%)

Cushion seats

(Each)

Black

Rough

5

Wooden table

Dark brown

Wenge Finish

7.58

Zone 3: Dining 2


24

Floor


Surface Area (m2)

Concrete

Smooth

Concrete

8

49.47

Walls

Component Details Surface

Finish

Reflectance Value (%)

Surface Area (m2)

C1

Brick

Plaster

Beige Paint

Glass

Steel Frame

Wall

Smooth

Glass Transparent

Glass

8

Beige Paint

63

Wall: 12.72

Glass: 10.91

Total: 23.63

C2

Brick

Plaster

Beige Paint

Glass

Steel Frame

Wall

Smooth

Glass Transparent

Glass

8

Beige Paint

63

Wall: 4.77 Glass: 9.08 Total: 13.85

25

C3

Brick

Plaster

Beige Paint

Glass

Steel Frame

Wall

Smooth

Glass Transparent

Glass

8

Beige Paint

63

Wall: 2.04

Glass: 4.12

Total: 6.16

C4

Brick

Plaster

Beige Paint

Smooth

Beige Paint

63

17.44

Ceiling


Surface Area (m2)

Concrete

Black Paint

Plywood

Smooth

Wood

10

Black Paint

4

Concrete:

39.04

Plywood:

10.43

Total: 49.47

26

Furniture

Component Details Colour Surface Finish


Cushion seats

Black

Rough

5

Wooden table

Brown

Matte

Smooth

10

Metal chair

Black

Matte

10

Zone 4: Kitchen / Work

Figure 2.21 Kitchen/Work Area

27

Floor


Surface Area (m2)

Concrete

Smooth

Concrete

8

12.19

Walls


Surface Area (m2)

D1

Plywood

Smooth

Matte

Wood

10

4.50

D2

Brick

Plaster

Beige Paint

Smooth

Beige Paint

63

13.95

D3

Brick

Plaster

Beige Paint

Timber Door

Smooth

Wood

10

Beige Paint

63

Wall: 2.76

Door: 1.94

Total: 4.70

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Ceiling

Furniture


Wood board

Brown

Smooth

Matte

10

Glass

Transparent

Smooth

8


Surface Area (m2)

Concrete

Black Paint

Smooth

Concrete

8

Black Paint

4

12.19

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Zone 5: Outdoor

Figure 2.22 Outdoor area

Floor


Surface Area (m2)

Concrete

Smooth

Concrete

8

44.41

Walls

Component Details Surface finish


Surface Area (m2)

E1

Brick

Plaster

Beige Paint

Glass

Steel Frame

Wall

Smooth

Glass

Transparent

Glass

8

Beige Paint

63

Wall: 12.72

Glass: 10.91

Total: 23.63

30

E2

Brick

Plaster

Beige Paint

Glass

Steel Frame

Wall

Smooth

Glass

Transparent

Glass

8

Beige Paint

63

Wall: 4.77 Glass: 9.08

Total: 13.85

E3

Brick

Plaster

Beige Paint

Glass

Steel Frame

Wall

Smooth

Glass

Transparent

Glass

8

Beige Paint

63

Wall: 2.04

Glass: 4.12

Total: 6.16

Furniture


Rotan timber material

Brown

Matte

Smooth

10

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2.4.2 Artificial Lightings in the Building

Figure 2.23 Position of lighting in the café

Symbol Image Lamps Colour Temperature

Colour Rendering

Net luminous

flux

Connected load

Luminous efficacy

LED

3000k

CRI > 80

700lm

11W

63lm/W

Fluorescent

3000k

CRI > 80

1140lm

14W

80lm/W

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2.4.3 Data Collection

Figure 2.24 Floor plan with grid lines

Position 1.00m height 1.00m Height 1.50m Height 1.50m Height

05:10PM (Evening)

08:00PM (Night)

05:10PM (Evening)

08:00PM (Night)

A/1 140 20 70 17 A/2 65 28 20 57 A/3 65 20 11 18 A/4 66 33 10 20 A/5 75 27 17 40 A/6 1800 28 75 12 A/7 16775 20 250 30 A/8 1780 26 1960 28 A/9 1563 27 1900 31 B/1 11 13 10 10

33

B/2 102 48 68 82 B/3 83 135 95 255 B/4 86 44 105 25 B/5 75 90 56 60 B/6 108 113 144 143 B/7 85 40 52 80 B/8 1870 32 1626 45 B/9 1797 30 1899 24 C/1 207 200 192 230 C/2 46 20 25 18 C/3 34 20 27 14 C/4 30 20 33 12 C/5 52 21 31 17 C/6 56 15 40 10 C/7 100 20 50 22 C/8 175 92 154 71 C/9 1183 36 1117 50 D/1 98 120 136 284 D/2 12 16 9 10 D/3 31 20 27 15 D/4 43 18 38 14 D/5 50 15 544 11 D/6 135 13 108 15 D/7 78 40 69 20 D/8 270 20 130 11 D/9 167 160 62 115 E/1 6 10 7 10 E/2 4 6 6 4 E/3 24 25 33 84 E/4 70 70 57 75 E/5 62 35 45 40 E/6 75 60 135 50 E/7 63 150 70 190 E/8 75 23 66 E/9 150 16 56 F/1 58 67 70 97 F/2 87 76 160 89 F/3 159 54 187 62 F/4 224 200 390 230 F/5 55 67 70 80 F/6 - - - - F/7 - - - - F/8 - - - - F/9 - - - -

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2.4.4 Calculation and Analysis

2.4.4.1 Day light factor calculation

Figure 2.25 The area whereby sunlight penetrates in.

Eo, Simultaneous outdoor

illuminance on a horizontal

plane from an unobstructed

hemisphere of overcast

sky, ( lux )

Ei, Average illuminance

due to daylight on the

indoor working plane,

( lux )

Day light factor,

DF=( Eo/ Ei ) x 100 %

32000

87.08

= (87.08/32000) x 100 %

=0.27

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Table 2.5 Daylight factor and distribution

Based on the table above, the day light factor of the case study, 0.27%, is considered poor.

However, the day light factor could be higher because most of the daylight is blocked by

the visor and the canvas.

Figure 2.26 Shows the daylight is partially blocked by the visor.

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Figure 2.27 shows the daylight is partially blocked by the canvas.

Figure 2.28 Shows the clear sky condition during our visit day.

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2.4.4.2 Lumen method calculation

Figure 2.29 Toilet zone

Total floor area ( m 2 ) 4.239

Type of lighting feature Fluorescent light

Mounting height, Hm ( m ) 2

Number of fixture, N 2

Lumen of Lighting fixture, F ( lm ) 3000

Maintenance factor ( MF ) 0.75

Reflectance - ceiling 0.7

-wall 0.3

Room Index ( 1.57 x 2.70 ) / 2 ( 1.57 + 2.70 ) = 0.50

Ultilization factor ( UF ) 0.22

Standard Illuminance ( lux ) 150

Current illuminance ( lux ) 233.55

Actual number of fixture needed, N N = (150 x 4.24) / 3000 x 0.75 x 0.22

= 1.28

= 1 light fixture is needed

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Type of lighting feature LED Spotlight






-wall 0.5

Room Index ( 5.10 x 2.32 ) /2 x ( 5.10 + 2.32 ) = 0.80





= 16.69

= 17 light fixtures are needed

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Type of lighting feature LED Spotlight






-wall 0.5

Room Index ( 13.76 x 7.12 ) /2 x ( 13.76 + 7.12 ) = 2.35





= 41.88


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Type of lighting feature LED Spotlight and fluorescent



Lumen of Lighting fixture, F ( lm ), halogen 700

Lumen of Lighting fixture, F ( lm ),

fluorescent

1140

Average Lumen ( 700 x 11 ) + 1140 / 12 = 736.67



-wall 0.5

Room Index ( 2.35 x 4.65 ) /2 x ( 2.35 + 4.65 ) = 0.8




Actual number of fixture needed, N N = (200 x 12.19) / 736.77 x 0.75 x 0.27

= 16.34


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2.4.5 Analysis diagram

Light Source Analysis

Figure 2.33 Section line on plan

Section A-A

Section B-B

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The spaces are mainly equipped with LED spotlight. Spotlight has very small light angle

therefore it only shines and provides light to a small area as shown in the section drawings.

During the day time, the space relies heavily on daylighting so each area gets their fair share

of light. However, during the night time, as the LED spotlight is unable to cover a big area,

leaving some bright, and some very dark. Though the space has a total of 36 ceiling

spotlights installed, it is still insufficient to cover the entire space or to achieve visual comfort.

Figure 2.34 The corners of the spaces are dark and no light shines there.

Ecotech simulation and analysis

Figure 2.34 The light contour for day time

It is quite clear that the lux value for the bottom part of the plan surpasses the other areas. This is because that’s the area where most of the glass panel are placed. Also it faces directly to the western sun. However, the simulation exceeded the data we got because in the actual building, the sunlight is partially blocked by the visors fixed on the surface of window.

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Figure 2.35 The light contour for night time

According to MS 1525, the illuminance for cafeteria is 200lux. As mentioned before, the angle of light is small. Hence, as the simulation shows, the difference of light received at different position. The simulation shows that the highest reading is more than 300, whereas the highest reading recorded is only 284lux. This could be caused by the minimal light fixture selection of the Ecotech itself. Aside from that, the simulation generally matches our data.

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2.5 Conclusion

The choice of lighting though does create a very modern, peaceful and homely atmosphere

which the shop wants to express. However, bases on the calculation and analysis, we can

conclude that the Brogues Coffee is lack of both artificial and natural light. In other words,

the lightings in this café is insufficient to achieve visual comfort for the users, and also to suit

the function of the space.

As seen in Figure 2.37 below, the back side of the space is dark. This is because the usage

of spotlight doesn’t not allow the whole room to be light up fully, which causes parts of the

spaces to be very bright, and parts of the spaces to be really dark. Though the reflectance

value of the beige colour wall is quite decent, the light hardly reaches the walls to be reflected

through the spaces. So, depending on where the user is within the space, the dullness and

darkness may make the user feel uncomfortable.

Also. there are large openings facing directly to the western sun. Though those opening are

partially blocked, the sunlight still manages to enter the building which causes glare problem.

This problem exists because the concrete floor reflects some of the sunlight into the building,

causing disturbance and discomfort to the users.

Figure 2.37 The glare problem exists within the building. (Photo taken at 5.30 pm)

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3.0 Acoustic

46

3.1 Introduction

It can be denied that acoustic design is another element that should well considerate in

architecture. Sound is similar to light in its movements, such that it could be reflected,

refracted, diffracted and others. The field of building acoustics consists of two parts; Room

Acoustics and Building Acoustics. Basically, room acoustics is related to the quality of sound

while building acoustics is related to unwanted sound, or noise.

To achieve comfort level, rate of sound input is compensated by the rate of energy absorbed

in the room. In other words, sound level in the room will be reduced if more absorbing

materials are brought in. Rooms with highly reflecting surfaces will have a relatively long

reverberation time while rooms with lots of absorbing materials will have short reverberation

times. In building acoustics, engineers concentrate on the noise level due to what goes on in

adjacent rooms (or outside) an important parameter is the sound insulation.

Source of noises can be from anywhere. It can happen from the slightest vibration that

happen inside or outside the building, but not all sound can be picked up by the human ear.

However, too much of noise may cause discomfort such as headache, or even hearing pain.

Hence, it is significant to preserve and enhance the desired level of sound, at the same time,

eliminating the excess, unwanted noise.

Figure 3.1 Range of audibility to the human ear

47

3.2 Journal

3.2.1 Introduction

St. Elizabeth of Hungary church

Figure 3.2 St. Elizabeth of Hungary in Jaworzno Szczakowa: a) view from outside b) interior

of the church

Building Information:

Name : St. Elizabeth of Hungary church

Project Completion : 1903

Function : Church

Location : Jaworzno Szczakowa, Hungary

The church consists of a chancel and three aisles delimited inside the columnar pillars on

which cross-ribbed vaulting rests. The interior has stylish neo-Gothic uniform accessories,

which include wooden altars (main and two side), a pulpit, baptismal font, confessionals,

pews and stained glass windows. The church is equipped with a pipe organ with 13 voices.

There is a stoneware floor. The volume inside the church, calculated using a 3D computer

model, equals 2249 m3. The maximum height of the nave is 10 m its width is 12.5 m.

48

3.2.2 Acoustic Analysis

Different acoustical methods have been carried out in order to determine the reverberation

time values and to develop a proposal solution for an acoustical improvement of the studied

church.

For the acoustic field evaluation, the following steps were proposed:

A) Calculation of reverberation time using empirical methods (Sabine)

B) Reverberation time measurements

C) Result interpretation verification of obtained values

D) Acoustic rehabilitation proposal

Reverberation Time Calculation

The first method applied is based on the Sabine eq., empirical formula based on the room

geometry and on the absorption characteristics of the room delimiting surfaces defined by

the calculation

𝑇 =0.161 𝑉

𝐴

Where,

T = reverberation time [s]

V = room volume [m3]

A = total absorption area [m3]

Figure 3.3 Obtained value using the Sabine equation are presented here

49

Reverberation Time Measurement

Figure 3.4 Ground plan with the sound source S (>) and microphone positions (1-10) for

measurements and pews zone (shaded area) for the St. Elizabeth of Hungary Church on Jaworzno

Szczakowa

To conduct a complete study of the room, methods of measuring acoustic data have also

been performed. The measurements for reverberation time, set according to the International

standard ISO 3382-1 requirements, were made by using special acoustic equipment (Bruel

& Kijaer Sound and Vibration Measurement) are composed of:

A) Pulse sound & vibration analyser

B) Building acoustic software

C) OmniPower Sound Source

D) Microphones

E) Power amplifier

F) Sound level calibrator

50

The measurements were taken inside the emptied church. According International Standards

ISO 3382-1, the reverberation time can be computed using different methods: interrupted

noise and integrated response to the impulse. In this case, the preferred method was

‘interrupted noise’, method comprising an omnidirectional sound source generating white

noise, which is a random signal with a flat power spectral density. The omnidirectional sound

source is composed of 12 speakers placed in such a way as to allow a spherical distribution

of the sound. According ISO 3382-1, the height of the sound source acoustic centre was

established at 1.5 m above the floor.

Acoustic model of the church

An acoustic model of the church has been developed by using the CATT-Acoustic v8

computer program. The location of the sound source and 10 test points in the model were

consistent with the location of the source and measuring points during in-situ measurements

in the church. The acoustic model consists of 918 surfaces. The reverberant sound

absorption coefficients α, chosen from the literature (MARTELLOTTA, 2009; MARTELLOTTA

et. Al., 2011; VORLANDER, 2008; CARMONA et. Al., 2009; MEYER, 2003) and assigned to

each area, correspond to the finishing materials of the church (Table 2.0.1).

Sound scattering coefficients s (Table 2.0.1_ were matched to the type of materials with

smooth surfaces (for example: walls or marble floor), moderately irregular (for example:

domes and arches) and irregular (for example: the altar) (ALONSO et. aL., 2014).

Figure 3.5 The acoustic model of the church, A0 – sound source, 1-10 – test points

51

Table 3.1. the reverberant sound absorption coefficients α, and the sound scattering

coefficients s in octave frequency bands of materials used in simulation tests.

Table 3.1 Adapted materials used for model calibration

Calibration of the acoustic model was carried out using the reverberation time. In the case of

this church the calibration process relied on adjusting the values of the sound absorption

coefficients α of the two materials with the largest percentage among all the finishing

materials, which were wall surfaces (31.6%) and domes and arches (33.4%). The values of

the sound absorption coefficients α of walls and domes and arches (Table 2.0.1) are similar

to those given in (VORLANDER, 2008) and (MARTELLOTTA, 2009), respectively. Such

adjustments ensured that satisfactory values of the simulated reverberation time were

obtained.

Comparisons of the reverberation time on octave frequency bands for the church without an

audience derived from T30 in-situ measurements and T30-unocc obtained from simulation tests

carried out on the model, are shown in the Table 2.0.2, along with the relative errors δ.

Table 1.5. Averaged, in space, values of the reverberation time in octave frequently bands

for the church without an audience derived from in-situ measurements T30 and obtained from

simulation tests T30-unocc carried out on the model, along with the relative errors δ.

52

Table 3.2 Values of T30 and T30-unocc

The values of T30 and T30-unocc varied less than 5% in each octave frequency band, which

corresponds to the Just Noticeable Difference (JND) threshold. Hence, it was assumed that

thee calibration of the church’s acoustic model was performed with sufficient accuracy

(VORLANDER M., 2008; BUENO et. aL., 2012). The temperature and humidity used in the

calibration of the model and in the simulation tests were the same as during in-situ

measurements in the church.

3.2.3 Conclusion

In churches, a favourable transmission of the sound level during liturgy through the entire

area occupied by the auditors is an essential requirement in the understanding process of

the spoken or sung words.

Research of this paper shows that the reverberation time values of the studied space were

sufficiently high to influence the communication activity.

Comfortable acoustic levels must be met in every hall in order to optimise the sound

transmission and listening conditions that are essential for every member of the audience.

53

3.3 Methodology

3.3.1 Preparation

1. Preliminary studies and identification of the spaces that we are choosing were studied

before we went to do the case study.

2. Choices of building were suggested for precedent studies to have a better understanding

of acoustics functioning would affect the surrounding of space.

3. After getting approved for the site as our case study, we made phone calls the shop to

have our permissions for our case study.

4. We obtained the plan drawing of the site from the owner of the shop.

5. We differentiated to a few spaces according to different function of the space.

6. We plotted a set of grid lines of 1.5m on the plan for recording later on.

7. Get the sound level meter from our university.

8. Understand how the device works in different conditions and situations before the site visit.

9. Study of basic standard and regulations such as CIBSE, ASHRAE and MS 1525 before

that to understand analyzing and comparing the data further on.

3.3.2 Acoustics data collection device

Figure 3.6 Sound level meter

54

A sound level meter is used for acoustic measurements. It is commonly a hand-held

instrument with a microphone attached at the top. The diaphrahm of the microphone

responds to changes in air pressure caused by sound waves. The instrument needs to be

adjusted so it knows the sensitivity of the particular microphone being used. Using this

information, the instrument is able to accurately convert the electrical signal back to a sound

pressure, and display the resulting sound pressure level (dB).

3.3.3 Acoustics data collection method

One of our group member prepared the orthographic drawings before we went for

the actual data collection day. We get our acoustic data measuring device, sound level meter

by lending from our university resources. We then went to our site which located in SS15 to

start our measuring work. We listed down all the acoustic sources that available in site

because it may affect our measurements. We set up a grid line of 1.5 meter of intervals for

the acoustic data collection after discussed with our lecturer. According to our gridlines, we

collected our acoustic data on every point of the gridlines by placing the device at a height

of 1 meter. We recorded the data on different time, which are the evening for the non-peak

hour and night for peak hour. We then insert all the lighting data into a table for further analysis.

https://en.wikipedia.org/wiki/Acoustics

https://en.wikipedia.org/wiki/Microphone

https://en.wikipedia.org/wiki/Diaphragm_(acoustics)

https://en.wikipedia.org/wiki/Sound_pressure

55

3.4 Acoustic Analysis

3.4.1 Building Components

Figure 3.7 Zoning

Zone 1: Toilet Zone

Figure 3.8 Toilet Area

56

Floor

Component Details Absorption

coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface Area

(m2)

Grey

Ceramic

Ceramic

0.01

Ceramic

0.01

Ceramic

0.02

4.23

Walls


coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface Area

(m2)

A1

Grey

Ceramic

Ceramic

0.01

Ceramic

0.01

Ceramic

0.02

4.70

A2

Grey

Ceramic

Ceramic

0.01

Ceramic

0.01

Ceramic

0.02

8.12

57

A3

Grey

Ceramic

Timber Door

Ceramic

0.01

Wood

0.15

Ceramic

0.01

Wood

0.10

Ceramic

0.02

Wood

0.10

Wall: 2.76

Door: 1.94

Total: 4.70

A4

Grey

Ceramic

Ceramic

0.01

Ceramic

0.01

Ceramic

0.02

8.12

Ceiling


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface Area

(m2)

Concrete

Plaster

White Paint

Brick

0.03

Plaster

0.01

Brick

0.03

Plaster

0.02

Brick

0.05

Plaster

0.04

4.23

58

Zone 2: Dining 1


Floor


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Laminated

Hard wood

Wood

0.15

Wood

0.10

Wood

0.10

11.83

Wall


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

B1

Brick

Plaster

Beige Paint

Brick

0.03

Plaster

0.02

Brick

0.03

Plaster

0.02

Brick

0.05

Plaster

0.04

6.96

59

B2

Brick

Plaster

Beige Paint

Brick

0.03

Plaster

0.02

Brick

0.03

Plaster

0.02

Brick

0.05

Plaster

0.04

15.30

B3

Brick

Plaster

Beige Paint

Brick

0.03

Plaster

0.02

Brick

0.03

Plaster

0.02

Brick

0.05

Plaster

0.04

6.96

Ceiling


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Concrete

Black Paint

Concrete

0.02

Concrete

0.05

Concrete

0.05

11.83

60

Furniture


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Cushion

seats

(Each)

0.12

0.28

0.28

Wooden

table

0.08

0.15

0.18

Zone 3: Dining 2


61

Floor


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Concrete

Concrete

0.02

Concrete

0.05

Concrete

0.05

49.47

Walls


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area

(m2)

C1

Brick

Plaster

Beige

Paint

Glass

Steel

Frame

Brick

0.02

Plaster

0.02

Glass

0.05

Brick

0.03

Plaster

0.02

Glass

0.15

Brick

0.04

Plaster

0.04

Glass

0.30

Wall:

12.72

Glass:

10.91

Total:

23.63

62

C2

Brick

Plaster

Beige

Paint

Glass

Steel

Frame

Brick

0.02

Plaster

0.02

Glass

0.05

Brick

0.03

Plaster

0.02

Glass

0.15

Brick

0.04

Plaster

0.04

Glass

0.30

Wall:

4.77

Glass:

9.08

Total:

13.85

C3

Brick

Plaster

Beige

Paint

Glass

Steel

Frame

Brick

0.02

Plaster

0.02

Glass

0.05

Brick

0.03

Plaster

0.02

Glass

0.15

Brick

0.04

Plaster

0.04

Glass

0.30

Wall:

2.04

Glass:

4.12

Total:

6.16

C4

Brick

Plaster

Beige

Paint

Brick

0.02

Plaster

0.02

Brick

0.03

Plaster

0.02

Brick

0.04

Plaster

0.04

17.44

63

Ceiling


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Concrete

Black Paint

Plywood

Wood

0.15

Concrete

0.02

Wood

0.12

Concrete

0.05

Wood

0.08

Concrete

0.05

Concrete:

39.04

Plywood:

10.43

Total: 49.47

Furniture


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Cushion

seats

(Each)

0.12

0.28

0.28

Wooden

table

0.08

0.15

0.18

64

Metal chair

0.07

0.14

0.14

Zone 4: Kitchen/Work


Floor


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Concrete

Concrete

0.02

Concrete

0.05

Concrete

0.05

12.19

65

Walls


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area

(m2)

D1

Plywood

Wood

0.15

Wood

0.12

Wood

0.08

4.50

D2

Brick

Plaster

Beige

Paint

Brick

0.02

Plaster

0.02

Brick

0.03

Plaster

0.02

Brick

0.04

Plaster

0.04

13.95

D3

Brick

Plaster

Beige

Paint

Timber

Door

Brick

0.02

Plaster

0.02

Wood

0.15

Brick

0.03

Plaster

0.02

Wood

0.10

Brick

0.04

Plaster

0.04

Wood

0.10

Wall:

2.76

Door:

1.94

Total:

4.70

66

Ceiling


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Concrete

Black Paint

Concrete

0.02

Concrete

0.05

Concrete

0.05

12.19

Furniture


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Wood board

0.15

0.10

0.10

Glass

0.05

0.15

0.30

67

Zone 5: Outdoor

Figure 3.12 Outdoor Area

Floor


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area (m2)

Concrete

Concrete

0.02

Concrete

0.05

Concrete

0.05

44.41

68

Walls


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Surface

Area

(m2)

C1

Brick

Plaster

Beige

Paint

Glass

Steel

Frame

Brick

0.02

Plaster

0.02

Glass

0.05

Brick

0.03

Plaster

0.02

Glass

0.15

Brick

0.04

Plaster

0.04

Glass

0.30

Wall:

12.72

Glass:

10.91

Total:

23.63

C2

Brick

Plaster

Beige

Paint

Glass

Steel

Frame

Brick

0.02

Plaster

0.02

Glass

0.05

Brick

0.03

Plaster

0.02

Glass

0.15

Brick

0.04

Plaster

0.04

Glass

0.30

Wall:

4.77

Glass:

9.08

Total:

13.85

69

C3

Brick

Plaster

Beige

Paint

Glass

Steel

Frame

Brick

0.02

Plaster

0.02

Glass

0.05

Brick

0.03

Plaster

0.02

Glass

0.15

Brick

0.04

Plaster

0.04

Glass

0.30

Wall:

2.04

Glass:

4.12

Total:

6.16

Furniture


Coefficient

(125 Hz)

Absorption

coefficient

(500 Hz)

Absorption

coefficient

(2000 Hz)

Rotan timber

material

0.1

0.08

0.08

70

3.4.2 Constant Source of Sound

Figure 3.13 Source of constant sound

Symbol Source of sound

Speakers

Kitchen appliances / Machines

71

3.4.3 Data Collection

Figure 3.14 Floor plans with grid lines

Position Non-Peak Non- Peak Peak 1st reading 2nd reading

A/1 60 61 65 A/2 60 63 65 A/3 58 62 68 A/4 55 61 64 A/5 58 67 65 A/6 55 64 70 A/7 58 63 72 A/8 62 56 75 A/9 59 64 77 B/1 59 60 62

72

B/2 59 63 60 B/3 61 78 55 B/4 59 62 60 B/5 59 60 62 B/6 57 65 58 B/7 56 64 60 B/8 60 66 70 B/9 59 65 72 C/1 59 65 62 C/2 58 68 65 C/3 60 86 65 C/4 65 75 70 C/5 57 62 65 C/6 57 65 68 C/7 56 60 62 C/8 59 60 65 C/9 59 66 75 D/1 59 66 66 D/2 60 70 71 D/3 59 68 68 D/4 58 62 65 D/5 58 65 70 D/6 57 62 59 D/7 57 60 64 D/8 58 58 68 D/9 60 65 88 E/1 58 65 60 E/2 59 65 65 E/3 59 80 82 E/4 59 63 76 E/5 58 60 71 E/6 57 63 65 E/7 57 58 63 E/8 58 55 65 E/9 60 63 66 F/1 51 55 55 F/2 51 53 57 F/3 55 60 88 F/4 56 65 80 F/5 56 58 76 F/6 - - - F/7 - - - F/8 - - - F/9 - - -

73

3.4.4 Calculation and Analysis

3.4.4.1 Sound level intensities calculation

Figure 3.15 Toilet Area

Non peak hour

Highest sound level = 55db

Using formula,

Swl = 10 log10 𝑙

𝑙0

Where 𝑙o = reference power intensity ( 1 x 10-12 watts )

55 = 10 log10 l / 1 x 10-12

l = 105.5 x 1 x 10-12

= 3.16 x 10-7

Lowest sound level = 53 db

53 = 10 log10 l / 1 x 10-12

l = 105.3 x 1 x 10-12

=1.99 x 10-7

Total intensity = ( 1.99 + 3.16 ) x 10-7

= 5.15 x 10-7 watts

Combine sound level = 10 log10 5.15 x 10-7 / 1 x 10-12

= 57.12 db

74

Peak hour

Highest sound level = 57 db

57 = 10 log10 l / 1 x 10-12

I = 105.7 x 1 x 10-12

= 5.01 x 10-7


55 = 10 log10 l / 1 x 10-12

I = 105.5 x 1 x 10-12

= 3.16 x 10-7


= 8.17 x 10-7 watt


= 59.12 db

Conclusion:

The combined sound level are 59.12 and 57.12 db respectively. The perceptible change is

around 1 db. Therefore even though the toilet is not occupied when we taking the

measurement, it can be conclude that there is an obvious change in sound level.

75


Non Peak hour


70 = 10 log10 l / 1 x 10-12

I = 107.0 x 1 x 10-12

= 1.0 x 10-5


60 = 10 log10 l / 1 x 10-12

I = 106.0 x 1 x 10-12

= 1.0 x 10-6

Total intensity = ( 1 + 0.1 ) x 10-5

= 1.10 x 10-5 watt


= 70.41 db

76

Peak hour


71 = 10 log10 l / 1 x 10-12

I = 107.1 x 1 x 10-12

= 1.26 x 10-5


65 = 10 log10 l / 1 x 10-12

I = 106.5 x 1 x 10-12

= 3.16 x 10-6


= 1.58 x 10-5 watt


= 71.99 db

Conclusion:

Same as the toilet, the difference of the sound level is around 1.6 and therefore there is a

noticeable change.

77


Non Peak hour


86 = 10 log10 l / 1 x 10-12

I = 108.6 x 1 x 10-12

= 3.98 x 10-4


55 = 10 log10 l / 1 x 10-12

I = 105.5 x 1 x 10-12

= 3.16 x 10-7


= 4.01 x 10-5 watt


= 76.0 db

78

Peak hour


88 = 10 log10 l / 1 x 10-12

I = 108.8 x 1 x 10-12

= 6.31 x 10-4


55 = 10 log10 l / 1 x 10-12

I = 105.5 x 1 x 10-12

= 3.16 x 10-7


= 6.31316 x 10-5 watt


= 88.00 db

Conclusion:

The sound level for peak hour is much greater than the non-peak. The number of occupant

is the main reason resulting the increase of sound level.

79


Non Peak hour


80 = 10 log10 l / 1 x 10-12

I = 108.0 x 1 x 10-12

= 1.0 x 10-4


58 = 10 log10 l / 1 x 10-12

I = 105.8 x 1 x 10-12

= 6.31 x 10-7

Total intensity = ( 0.00631 + 1 ) x 10-4

= 1.00631 x 10-4 watt


= 80.00 bd

80

Peak hour


88 = 10 log10 l / 1 x 10-12

I = 108.8 x 1 x 10-12

= 6.31 x 10-4


71 = 10 log10 l / 1 x 10-12

I = 107.1 x 1 x 10-12

= 1.26 x 10-5


= 6.436 x 10-4 watt


= 88.09 db

Conclusion:

The kitchen is the nosiest zone overall. The sound made by the blender machine results the

high sound level and when it is not used, the sound level of this zone remains around the

same as the other. ( 58 db )

81

Figure 3.19 Outdoor Area

Non Peak hour


62 = 10 log10 l / 1 x 10-12

I = 106.2 x 1 x 10-12

= 1.58 x 10-6


55 = 10 log10 l / 1 x 10-12

I = 105.5 x 1 x 10-12

= 3.16 x 10-7


= 1.896 x 10-6 watt


= 62.78 db

82

Peak hour


77 = 10 log10 l / 1 x 10-12

I = 107.7 x 1 x 10-12

= 5.01 x 10-5


64 = 10 log10 l / 1 x 10-12

I = 106.4 x 1 x 10-12

= 2.51 x 10-6


= 5.261 x 10-5 watt


= 77.21 db

Conclusion:

The great difference could be the sound generated by vehicle and the music retail right

opposite of the coffee shop. Since the peak hour is 8.00pm, that’s the time whereby people

having their dinning therefore higher sound level is recorded.

83

3.4.4.2 Calculation of reverberation time

Reverberation time

Reverberation time is defined as the length of time required for sound to decay 60 dB from

its initial level. Designer sometimes incorporate RT when they designing to either allow the

space to be more lively by lengthening the RT and vice versa. The length of RT is closely

related to material coefficient and the volume of the enclosed space.

.

Figure 3.20 Enclosed space of the Brogues coffee

84

At 125 Hz


Element Material a S ( m2 ) A

Floor Laminated hard wood 0.15 11.83 1.7745

B1 wall painted plaster brick wall 0.02 6.96 0.1392



Roof rough concrete 0.02 11.83 0.2366

Occupant 0.21 4 0.84

chair cusion 0.12 8 0.96

table wood 0.08 2 0.16

Total A 4.5555

85



Floor smooth unpainted concrete 0.01 49.47 0.4947

c1 wall painted plaster brick wall 0.02 12.72 0.2544

c1 wall glass 0.05 10.91 0.5455


c2 wall glass 0.05 9.08 0.454


c3 wall glass 0.05 4.12 0.206


c5 wall plywood 0.15 4.5 0.675



c7 wall Wood hollow core door 0.3 1.94 0.582

ceiling concrete 0.02 39.04 0.7808

86

ceiling wood 0.15 10.43 1.5645

Occupant 0.21 14 2.94

chair cushion 0.12 24 2.88


chair metal 0.07 3 0.21

Total A 12.8861


Element material a S ( m2 ) A

Floor concrete 0.02 12.19 0.2438

D1 wall plywood 0.15 4.5 0.675

D2 wall painted plaster brick wall 0.02 13.95 0.279


D3 wall wood 0.15 1.94 0.291


Total A 1.7878

87

Using formula,

RT = 0.16 x V

A

Whereby V is the volume of the enclosed space

and A = a x S

a is the absorption coefficient and S is the surface area

Total A of 3 zones = 1.7878 + 4.5555 + 12.8816

= 19.2294

Volume = 3 x ( 12.19 + 11.83 + 49.47 )

= 220.47

RT = 0.16 x 220.47

19.2294

= 1.83 s

The reverberation time for 125 Hz is 1.83s.

88

At 500 Hz











Total A 6.7389

89


Element Material a S

( m2 )

A

Floor smooth unpaint concrete 0.02 49.47 0.9894


c1 wall glass 0.15 10.91 1.6365


c2 wall glass 0.15 9.08 1.362


c3 wall glass 0.15 4.12 0.618






90


ceiling wood 0.12 10.43 1.2516

Occupant 0.46 14 6.44




Total A 23.774


Element material a S ( m2 ) A





D3 wall wood 0.1 1.94 0.194


Total A 2.2872

91

Total A of 3 zones = 6.7389 + 23.774 + 2.2872

= 32.8002

Volume = 3 x ( 12.19 + 11.83 + 49.47 )

= 220.47

RT = 0.16 x 220.47

32.8002

= 1.08 s

The reverberation time for 500 Hz is 1.08 s.

92

At 2000 Hz



( m2 )

A









Total A 6.9989

93



( m2 )

A

Floor smooth unpainted

concrete

0.02 49.47 0.9894


c1 wall glass 0.3 10.91 3.273


c2 wall glass 0.3 9.08 2.724


c3 wall glass 0.3 4.12 1.236






94


ceiling wood 0.08 10.43 0.8344

Occupant 0.51 14 7.14




Total A 19.776


Element material a S

( m2 )

A





D3 wall wood 0.1 1.94 0.194


Total A 2.1072

95

Total A of 3 zones = 6.9989 + 19.776 + 2.1072 = 28.8825

Volume = 3 x ( 12.19 + 11.83 + 49.47 )

= 220.47

RT = 0.16 x 220.47

28.8825

= 1.22 s

The reverberation time for 2000 Hz is 1.22 s.

Conclusion:

The reverberation time is between 1 to 2 second when frequency of sound 125, 500 and

2000 Hz.

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2.4.4.3 Calculation of Sound Reduction Index / Transmission loss

Calculating sound reduction index is good for designer to know whether the space is well

sound proof or not. Sound reduction index tells us that how effective the materials at reducing

the sound.

Figure 3.30 Materials transmission loss under different frequency.

According to Saint-Gobain, a global force in engineered materials, transmission loss provides

more information than STC because it covers bigger range of frequency. There are few

common ways to reduce the unwanted sound, one is by adding drywall on wall and ceiling

or just build a cavity wall.


97

Using formula

SRI = 10 log10 ( 1 / T )

Where by T = Transmission coefficient of material

For plastered brick painted wall,

44 = 10 log10 ( 1 / T )

T = 1 / 104.4

T = 3.98 x 10-5

For glass,

26 = 10 log10 ( 1 / T )

T = 1 / 102.6

T = 2.52 x 10-3

For steel frame,

42 = 10 log10 ( 1 / T )

T = 1 / 104.2

T = 5.69 x 10-5

Element S ( m2 ) SRI T T x S

painted plaster brick

wall 19.53 44 3.98 x 10 -5 7.78 x 10-4

glass 24.11 26 2.51 x 10 -3 6.06 x 10-2

steel frame 0.9024 42 6.30 x 10 -5 5.70 x 10-5

98

Using formula,

TL = 10 log10 1

Tav

Tav = ( 6.06 + 0.0778 + 0.0057 ) x 10 -2

Tav = 6.14 x 10 -2

TL = 10 log10 ( 1 / 6.14 x 10 -2 )

TL = 28.61 db


For plastered brick painted wall,

44 = 10 log10 ( 1 / T )

T = 1 / 104.4

T = 3.98 x 10-5

For steel frame,

30 = 10 log10 ( 1 / T )

T = 1 / 103.0

T = 1.0 x 10-3

99

Element S ( m2 ) SRI T T x S

painted plaster brick

wall 13.95 44 3.98 x 10-5 5.55 x 10-4

wood 1.94 30 0.001 1.94 x 10-3

Using formula,

TL = 10 log10 1

Tav

Tav = ( 1.94 + 0.555 ) x 10 -3

Tav = 2.50 x 10 -3

TL = 10 log10 ( 1 / 2.50 x 10 -3 )

TL = 26.02 db


Since plastered brick painted wall is the only material, therefore the TL is 44db.

Conclusion:

Based on the calculation, the loss of transmission is the highest compare to the other

zones.

100

3.4.5 Analysis Diagrams

Ecotech Simulation at 500 Hz

Figure 3.34 shows the sound generated by 1 speaker

The figure shows the simulation of sound travels within the space. In this case, only the sound

of 1 speaker is generated. The sound travels to the other end of the building and minor

reverberation time occurs nearby the source of sound. Only 3 major types of sound are

present, Direct sound, Reverb sound and Masked sound.

Figure 3.35 shows the sound generated by the electrical appliances

The figure shows the simulation of sound of blender machine travels within the space. Since

this sound is the nosiest and causes the customer feels uncomfortable as there are some

students actually studying in the cafe. It can clearly be seen that the directly sound is

mostly at the zones where customer sits. Therefore, in this simulation we conclude that the

101

sound made by electrical appliances is the major acoustic issue. Partition may be installed

to minimize the unwanted sound.

Figure 3.36 shows the overall sound within the building

This figure shows the sound generated by all the speakers and electrical appliances. We

conclude that the zone where customers sit receive sound from various sources. There is a

clear reverberation occurs at the kitchen zone because this zone is small and has 3 sides

enclosed. The cafeteria generally fulfilled the requirement of stated except the time blender

machine start working.

102

3.4.6 Acoustic evaluation and conclusion The transmission loss of sound of Brogues coffee is generally fine as it reduces almost 30dB

from the external sound source. Whereas for the reverberation time, the time range is

between 1 to 2 seconds. There is not much sound reflected within the building, therefore

users can carry out their conversation without worries of disturbing the other users within the

space.

However, since the scale of the cafe is not big, therefore people find that the noise generated

by the kitchen gadget is loud and noisy especially from the blender machine and coffee

beans grinder. Sometimes, loud honks and exhaust sound from the vehicles directly outside

the cafe can also disturb the users inside the space.

103

4.0 Conclusion

Overall, based on the calculation and analysis, we can conclude that this café performs

decently in its acoustic performance, but its lighting performance is still insufficient.

Brogues Coffee is lack of both artificial and natural light. During the day, the large openings

cases glare to the users inside at certain times. At other times, even though there are many

openings around, the natural sunlight is partially shaded or blocked. Those under the light

may experience a decent amount of slight shining at they are, but the dark corners of the

café may cause the users at those areas some hard time to carry out some activity such as

reading. Though the beige colour paint at the wall is able to reflect light properly, it wasn’t

utilised. Hence, leaving the area with patches of bright and dark during the night. With that,

the lightings in this café is insufficient to achieve visual comfort, nor to suit the function of the

space.

The acoustic performance, however, is pretty decent. It reduces sufficient external noises,

and the reverberation time is only between 1 to 2 seconds. Reflection of sound in the space

is also properly controlled. However, due to the size of the space, the noises from kitchen

appliances may cause some disturbance to the users.

104

Reference

Absorption Coefficient Chart - Soundproof Your Home. (n.d.). Retrieved November 06, 2016, from http://soundproofyourhome.com/absorption-coefficient-chart/

ABSORPTION COEFFICIENTS - acoustic. (n.d.). Retrieved November 6, 2016, from http://www.acoustic.ua/st/web_absorption_data_eng.pdf

Acoustics in Buildings. (n.d.). Retrieved November 2, 2016, from http://acoustic-products.co.uk/faq/acoustics-in-buildings/

L. (2016). LRV Light Reflectance Value of Paint Colors - TheLandofColor.com. Retrieved November 06, 2016, from http://thelandofcolor.com/lrv-light-reflectance-value-of-paint-colors/

Light in Architecture. (2015, January). Light in Architecture. Retrieved November 03, 2016, from https://light2015blog.org/2015/01/27/light-in-architecture/

Reverberation Time - Georgia State University. (n.d.). Retrieved November 4, 2016, from http://hyperphysics.phy-astr.gsu.edu/hbase/acoustic/revtim.html Understanding transmission loss | Green Glue. (n.d.). Retrieved November 04, 2016, from http://www.greengluecompany.com/benefit/how-green-glue-works/understanding-transmission-loss

Varrichione, A., & Jarvis, E. (2015, May). LIGHTING STUDY OF THE GEORGE C. GORDON LIBRARY.

http://soundproofyourhome.com/absorption-coefficient-chart/

http://www.acoustic.ua/st/web_absorption_data_eng.pdf

http://acoustic-products.co.uk/faq/acoustics-in-buildings/

http://acoustic-products.co.uk/faq/acoustics-in-buildings/

https://light2015blog.org/2015/01/27/light-in-architecture/

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