ARC 3413
BUILDING SCIENCE 2
_________________________________________________________________
PROJECT 1: LIGHTING & ACOUSTIC PERFORMANCE EVALUATION AND DESIGN OF CORE DESIGN GALLERY
TUTOR : MR SIVA
Azin Eskandari
0312234
Feiven Chee
0312004
Lee Min
0308860
Mohammad Syarulnizam Mohd Nasir
0302549
Muhammad Haziq bin Ariffin
0311763
Oh Keng Yee
0312501 Page | 1
Abstract
4
1.0
Introduction
5
1.1
Aim and Objectives
6
1.2
Site Study
7
1.2.1 Introduction
7
1.2.2 Reason for Selection
8
1.2.3 Measured Drawings
9
2.0 2.1 3.0
Methodology Sequence of working Lighting
11 11 13
3.1 Literature Review 3.1.1 Importance of Light in Architecture 3.1.2 Natural Daylighting & Artificial Electrical Lighting 3.1.3 Balance between science and arts 3.1.4 Daylight Factor 3.1.5 Lumen Method
13 13 13 13 14 15
3.2 Precedent Study 3.2.1 Cambria Office Building 3.2.2 Menil Collection
16 16 28
3.3 Site Study 3.3.1 Zoning of Spaces 3.3.2 Tabulation of Data 3.3.3 Daylight Factor Analysis 3.3.4 Types and Specifications of Lighting Used 3.3.5 Artificial Light Analysis 3.3.6 Analysis & Evaluation
30 30 33 35 38 39 54
4.0
Acoustics
55
4.1 Literature Review 4.1.1 Architectural Acoustics 4.1.2 Sound Pressure Level 4.1.3 Reverberation Time 4.1.4 Sound Reduction Index 4.1.5 Issues of Acoustic System Design 4.1.6 Acoustic Design for Galleries
55 55 55 56 57 58 59
4.2 Precedent Study 4.2.1 Introduction to the Building 4.2.2 Selection of Interior Surface Materials: 4.2.3 Measurement and Analysis 4.2.4 Background Sound Level (BSL)
60 60 60 62 63
4.2.5 4.2.6 4.2.7 4.2.8 4.2.9
Early Decay Time (EDT) Definition (D50) Speech Transmission Index (STI) Total Sound Level (TSL) Evaluation and Conclusion
4.3 Site Study 4.3.1 Outdoor Noise Sources 4.3.2 Tabulation of Data 4.3.3 Indoor Noise Sources 4.3.4 Calculation of Sound Pressure Level 4.3.5 Zoning of Spaces 4.3.6 Calculation of Sound Pressure Levels 4.3.7 Tabulation of Sound Pressure Levels 4.3.8 Analysis 4.3.9 Conclusion 4.3.10 Spaces Acoustic Analysis 4.3.11 Analysis for Data Collection SPL and Standard Equipment SPL 4.3.12 Reverberation Time 4.3.13 Sound Reduction Index 4.3.14 Sound Reduction Index Analysis and Conclusion 5.0
Evaluation and Conclusion
63 64 66 67 67 69 69 70 72 76 79 83 88 89 89 90 93 94 102 105 106
5.1 Lighting 5.1.1 Improvements for Lighting 5.1.2 Limitations with Lighting
106 106 106
5.2 Acoustics 5.2.1 Improvements for Acoustics 5.2.2 Limitations with Acoustics
106 106 107
5.3
107
Conclusion
References
108
Appendix
110
Abstract This report contains the details of the study conducted on CORE Design Gallery with regards to the lighting and acoustical performances. The report is broken down into two major segments – Lighting followed by Acoustics. Included are the technical data such as formulas, equations and calculations that estimate both illuminance levels as well as noise levels for both light and acoustics. All orthographic drawings and diagrams were made with data collected from measurements done on site. The analysis diagrams were made with Autodesk Ecotect, an analysis software. A list of figures and tables used as well as references are provided at the end of the report to ease with navigation.
1.0 Introduction
Lighting design is one of the major elements when it comes to architecture design, in interior as well as exterior architecture. The texture, colors, solid volumes and enclosed spaces can only be appreciated and enhanced fully when they are lit imaginatively. This project exposes and introduces students to daylighting and artificial lighting requirements in a suggested space. Acoustic design in architecture is an element which the control of sound in spaces is to be concerned especially for enclosed spaces. The requirements vary in relation to different functional spaces. It is essential to preserve and enhance the desired sound and to eliminate noise and undesired sound. This project exposes and introduces students to acoustic design and acoustical requirements in a suggested space. In a group of six, we have chosen The Core Design Gallery, located at SS15, Selangor as our site of study. We have conducted several visits to our site to ensure the success of our project outcome. Measured drawings, lightings and acoustics measurements as well as photographs have been taken while we were on site. We have also done calculations and analysis to the results of our observations and recordings.
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1.1 Aim and Objectives The aim and objectives of this project is as the following:
To understand the day-lighting, lighting and acoustic characteristics.
To understand the lighting and acoustic requirement in a suggested place.
To determine the characteristics and function of day-lighting, artificial lighting, sound and acoustic within the intended space.
To critically report and analyze the space and suggest remedies to improvise the lighting and acoustic qualities within the space.
This project also aims to provide a better understanding on the relationship between the type of materials that are employed in terms of building materials as well as internal furnishings and finishes as well as their impacts on acoustical and lighting conditions in the building based on the building’s functions. Understanding the volume and area of each functional space also helps in determining the lighting requirements based on acoustical or lighting inadequacy that is reflected in the data collection. Acknowledging adjacent spaces is also vital to address acoustic concerns. In terms of lighting, specifications of luminaries, height of each type of light as well as the existence of fenestrations will help to understand the lighting conditions within each space. Backed up with precedent studies, drawing comparison with our site study, our precedent studies will aid in determining the different types of lighting and acoustic
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1.2 Site Study 1.2.1 Introduction
Figure 1: View from Entrance of CORE Design Gallery
Case study
: The Core Design Gallery
Type of space
: Old Terrace House Transformed into Modern Art Gallery
Address
: Core Design Gallery, 87, Jalan SS15/2A Subang Jaya 47500 Selangor Darul Ehsan
The Core Design Gallery is a unique art space and gallery which was originally a residential home. This is where one could appreciate contemporary art works from Malaysian and regional artists at a luxury and comfortable environment. The cozy and homey scenario allows the art pieces to stand out through a spacious environment which is both elegant and prestigious. Core Design functions as a gallery for shows while they are also involved with consultancy services to provide advice and solutions in design for its customers who stem from individuals to corporations. The transition from an old terrace house to a modern art gallery is Core Design’s most distinguished element as it projects the fusion of tradition with contemporary art in Malaysia today.
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1.2.2 Reason for Selection In terms of acoustics issues, CORE Gallery is located along the edge of Subang Jaya’s SS15 residential district facing a main road that is almost congested during peak hours. There is also a large contrast in human activities within the building during peak (activity during exhibition events) and non-peak (staff working activity) hours. The sensitivity of paintings with regards to artificial lighting and day lighting is a big consideration that should be acknowledged as part of the list of lighting issues that is present within the building. In addition to that, the building also provides a sufficient number of a variety of functional spaces to analyze the different acoustic and lighting conditions for each space. With the main gallery area that acts as a public space with storage and office areas that act as private spaces that are restricted to the building’s staff would help in understanding how each space develops different acoustical and lighting conditions to facilitate different programmes and functions. The barren structural finish would also prove to be an aspect that can be learnt from especially for the sloping roofline where there is no false ceiling to help act as an acoustic buffer within the building. Unlike the ground floor gallery space, the first floor gallery space with its sloping roofline and a mixture of opaque and transparent surfaces of materials will aid in better understanding the building’s response to acoustic and lighting conditions.
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1.2.3 Measured Drawings
Figure 2: Ground Floor Plan (not to scale)
Figure 3: First Floor Plan (not to scale)
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Figure 4: Roof Plan (not to scale)
Figure 5: Section of Building (not to scale)
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2.0 Methodology 2.1
Sequence of working
PRECEDENT STUDIES Took documentation journals that consisted lightings and acoustics study similar to the selected site spaces as precedent studies. Read through and analyzed, extracting out important information and diagrams for later analysis and reference on site. PREPARATIONS Plans, section and elevation drawings were taken from the management of the gallery. Grid lines with 1.5m distance apart were then applied to the plans for later data collecting and recording purpose. The methods of using the Lux Meter and Sound Level Meter were tried and learned before heading to the site. Basic standard and regulations such as CIBSE, AHSRAE and MS1525 were studied and points were extracted out for further analysis and comparison.
Figure 6: Plan showing data collection points
Figure 8: Lutron digital lux meter LX-101
Figure 7: 01dB digital sound meter
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SITE VISIT We were only permitted to analyze and take recordings of the first floor of the gallery as the ground floor was excluded due to private working spaces. The first floor is also where most of the artworks are exhibited and events are held. We went to the site twice during peak hours (events), 7pm and non-peak hours, 1pm. Based on observations on the number of mechanical equipment that exist in our site as well as the amount of human activities that take place within and around the building, photographs are taken to account these evidences. RECORDING DATA
Figure 9: Reading Interval for Lighting
Figure 10: Reading Interval for Acoustics
Data collection for lighting was conducted using the Lux Meter. Readings were taken at 1.5m intervals at a sitting position of 1m and 1.5m. For acoustics, the data collection was conducted using the Sound Level Meter. Readings were taken at 1.5m intervals at a position of 1m above ground. For both lighting and acoustics measurement, they are taken at every intersection of grid line in the plan, which is every 1.5m distance apart. The procedure is repeated once more to ensure the accuracy of the readings. The readings were then analyzed and compared to the standard comparison tools such as CIBSE, ASHRAE, MS1525 and LEEDS. The materiality of each component of the spaces was also recorded. DIAGRAMMING Sound contour diagram and lighting contour diagram were established to understand the concentrations of noise and lightings for different parts of our area of study. CALCULATIONS Calculations are carried out to understand the acoustical and lighting effectiveness of the particular space. CONCLUSION By understanding the acoustical and lighting diagrams and recorded readings, we are able to deduce the cause for certain noise peaks as well as trace its sources and also to understand the suitability of lighting specification in spaces. Eventually, suggest measures to help reduce these surges in noise levels and also to improve the lighting quality of the spaces. Page | 12
3.0 Lighting 3.1
Literature Review
3.1.1
Importance of Light in Architecture The perception of space is directly connected to the way light integrates with it. What
we see, what we experience and how we interpret the elements is affected by how light interacts with us and with the environment. Regarding architecture, in whatever dimension it can be analyzed, either as space, as material or as color, it is essentially dependent on the lighting situation that involves both the object and the observer. The dynamic daylight and the controlled artificial lighting are able to affect not only distinct physical measurable conditions in a space, but also to instigate and provoke different visual experiences and moods. Due to the light, it is possible to perceive different atmospheres in the same physical environment. Light constitutes an element of fundamental relevance for the design of spaces and therefore it plays a significant role in the discussion of quality in architecture. 3.1.2
Natural Daylighting & Artificial Electrical Lighting Although architects should always strive towards achieving a building which can draw
in as much natural daylighting as possible, it is almost impossible to go on without electrical lighting taking into consideration that a building should function both day and night. In addition, certain building typologies and functions are not suited for daylighting such as museums and galleries as exposure to the natural light could damage the artifacts. It is important to understand the limitations and opportunities in using natural daylighting as well as artificial lighting and be able to apply it architecturally to achieve the best performing building. 3.1.3
Balance between science and arts It is important that the sciences of light production and luminaire photometric are
balanced with the artistic application of light as a medium in our built environment. Electrical lighting systems should also consider the impacts of, and ideally be integrated with, daylighting systems. Architectural lighting design focuses on three fundamental aspects of the illumination of buildings or spaces. The first is the aesthetic appeal of a building, an aspect particularly important in the illumination of retail environments. Secondly, the ergonomic aspect: the measure of how much of a function the lighting plays. Thirdly is the energy efficiency issue to
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ensure that light is not wasted by over-illumination, either by illuminating vacant spaces unnecessarily or by providing more light than needed for the aesthetics or the task. Each of these three aspects is looked at in considerable detail when the lighting designer is at work. In aesthetic appeal, the lighting designer attempts to raise the general attractiveness of the design, measure whether it should be subtly blended into the background or whether it should stand out, and assess what kind of emotions the lighting should evoke. The functional aspects of the project can encompass the need for the project to be visible (by night mostly, but also by day), the impact of daylight on the project and safety issues (glare, colour confusion etc.). 3.1.4
Daylight Factor
Daylight Factor is a ratio that represents the amount of illumination available indoors relative to the illumination present outdoors at the same time under overcast skies. It is used in architecture to assess the internal natural lighting levels as perceived on the working plane or surface, in order to determine if there is sufficient natural lighting for the occupants of the space to carry out their normal duties. It is the ratio of internal light level to external light level. Daylight Factor is defined as follows: đ??ˇđ?‘Žđ?‘˘đ?‘™đ?‘–đ?‘”â„Žđ?‘Ą đ??šđ?‘Žđ?‘?đ?‘Ąđ?‘œđ?‘&#x;, đ??ˇđ??š =
đ??źđ?‘›đ?‘‘đ?‘œđ?‘œđ?‘&#x; đ??źđ?‘™đ?‘™đ?‘˘đ?‘šđ?‘–đ?‘›đ?‘Žđ?‘›đ?‘?đ?‘’, đ??¸đ?‘– đ?‘Ľ 100% đ?‘‚đ?‘˘đ?‘Ąđ?‘‘đ?‘œđ?‘œđ?‘&#x; đ??źđ?‘™đ?‘™đ?‘˘đ?‘šđ?‘–đ?‘›đ?‘Žđ?‘›đ?‘?đ?‘’, đ??¸đ?‘œ
Where, Ei = illuminance due to daylight at a point on the indoors working plane, Eo = simultaneous outdoor illuminance on a horizontal plane from an unobstructed hemisphere of overcast sky.
Zone
DF (%)
Very bright
>6
Bright
3-6
Distribution Very large with thermal and glare problem Good
Average
1-3
Fair
Dark
0-1
Poor
Table 1: Daylight factors and distribution (Department of standards Malaysia, 2007)
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3.1.5
Lumen Method The Lumen Method is used to determine the number of lamps that should be
installed for a given area or room, which in this case, we already have the number of fixtures, therefore we calculate the total illuminance of the space based on the number of fixtures and determine whether or not that particular space has enough lighting fixture.
The number of lamps is given by the formula: đ?‘ =
Where,
đ??¸đ?‘Ľđ??´ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š
N = number of lamps required. E = illuminance level required (lux) A = area at working plane height (m2) F = average luminous flux from each lamp (lm) UF = utilisation factor, an allowance for the light distribution of the luminaire and the room surfaces. MF = maintenance factor, an allowance for reduced light output because of deterioration and dirt.
Room Index, RI, is the ratio of room plan area to half the wall area between the working and luminaire planes: đ?‘…đ??ź = where,
L
đ??żđ?‘Ľđ?‘Š đ??ťđ?‘š đ?‘Ľ ( đ??ż + đ?‘Š )
= length of room
W = width of room Hm = mounting height, i.e. the vertical distance between the working plane and the luminaire
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3.2
Precedent Study
3.2.1
Cambria Office Building
3.2.1.1 Introduction to the Building The Cambria Office Building in Ebensburg, Pennsylvania is a two-story, 3,205m2 structure serves as the district office for Pennsylvania’s Department of Environmental Protection (DEP). It is oriented on a long east-west axis. The building contains office space for approximately 100 people, a large file storage area, two small laboratory areas, conference rooms, a break room, and general storage areas. The design team used the U.S. Green Building Council’s LEED 2.0 requirements as design guidelines and goals, ultimately striving for and achieving a “high performance” classification. Among the low-energy design features used in this building are ground-source heat pumps, an under-floor air distribution system, heat recovery ventilators, an 18.2-kW PV system, daylighting, motion sensors, additional wall and roof insulation, and highperformance windows. The selection of finishes, including carpets, walls, furniture, and paints, was based on recycled content and low emissions. The integrated energy design of this all-electric building produced an energy saving of 40% and an energy cost saving of 43% when compared to ASHRAE. The lighting and HVAC efficiencies accounted for most of the savings. Some daylighting was used, but saved minimal energy.
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3.2.1.2 Drawings
Figure 11: First Floor Plan of Cambria Office Building
Figure 12: Second Floor Plan of Cambria Office Building
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3.2.1.3
Lighting Design Intention and Description One of the main issues the building was to address was to reduce the use of energy
for electrical lighting, and it was emphasized that this needed to be addressed early on in the design. It was done so through the orientation according to the east-west axis to optimize daylight into the building. The rooflines were sloped in order to allow the use of north- and south-facing clerestory windows on the second floor for daylighting, which also provided an angled surface for mounting PV panels. Light shelves were added on the south side of the first floor to help direct some daylight deeper into the office space. These daylighting features are illustrated in Figure 3-1. To improve the success of the daylighting, the second floor plan was designed to place the large open office spaces adjacent to exterior walls and locate enclosed offices in the center of the building rather than at the perimeter. As a result, these private offices do not block access to daylight, and the vast majority of occupants are given access to this daylight and views. Most of the occupants were located in these large open office spaces on the second floor because of their access to daylighting. The first floor was designed to accommodate meeting spaces, storage, support functions, and workspace for field staff who spend the majority of their time away from the office.
Figure 13: Daylighting design features of the Cambria Building
The lighting design was a combined effort by the architect, electrical contractor, energy consultant, and a product sales representative. They decided to use a lighting system that provided 30 foot candles (323 lx) of ambient light with under cabinet task lighting at workstations for extra light. 30 foot candles of ambient light are a common specification for the warehouse typology in the US. Daylighting was an important part of the design and resulted in the use of clerestory windows, overhangs, light shelves, and a dimming system.
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The initial lighting design called for a lighting power density (LPD) of 0.82 W/ft 2 (8.8 W/m2). Subsequent refinement of the lighting system resulted in a final design LPD of 0.75 W/ft2 (8 W/m2), not including task lighting. The LPD of the task lighting in the office areas is approximately 0.5 W/ft2 (5.4 W/m2). The final design met the illumination recommendations of the Illuminating Engineering Society of North America (IESNA 2000) while reducing the first cost by more than $3,600 and reducing the energy costs by more than $1,800 per year compared to the original design. Following occupancy, a couple of minor issues arose with regard to HVAC and lighting. Three areas were identified which required additional illumination: 1. The file room lighting system was supplemented with three continuous rows of surface mount, two-tube fluorescent fixtures controlled by a timer switch, and the existing three-tube parabolic fluorescent fixtures were moved to the corridors on either side of the files. 2. An additional row of indirect fixtures (removed from the file room) was installed in a second-floor conference room. 3. Additional compact fluorescent task lighting was purchased for the tables in the
supervisor offices and the draft tables in a few of the cubicles. The luminaires in the open office areas are indirect fixtures with 32-W T-8 fluorescent lamps with an installed capacity of 0.75 W/ft2 (8.1 W/m2). The LPD of the task lighting in the office areas is approximately 0.5 W/ft2 (5.4 W/m2). The luminaires in the second-floor offices have dimmable ballasts controlled by lighting sensors in each of the office areas. Under cabinet task lighting in each cubicle is controlled by a motion sensor connected to a power strip. Compact fluorescent lamps are used in other areas of the building such as the restrooms and lobby. Occupancy sensors are installed on the restroom lighting. Timing circuits in the breaker boxes control the building ambient and exterior lighting systems with override switches near the main entrance.
Almost all fenestration faces either north or south and the design incorporate clerestory windows facing north and south along the center of the building. The south-facing clerestory windows are equipped with motorized sunscreens controlled by a photosensor to block direct-beam radiation. Overhangs shade the second floor windows on the south elevation. Light shelves are installed on the south-facing, first-floor windows. Page | 19
The interior finishes were selected to improve the light reflection and provide contrast. The first-floor ceiling tiles have a light reflectance of 89%, the second floor has high vaulted white ceilings with an open truss construction, the bottom 2.5 ft (0.8 m) of the walls are a light, natural wood color, the top portion of the walls are painted off-white (light reflectance of 75%), and the cubicle dividers are off-white. The carpet and the desktops are black. The IESNA Lighting Handbook recommends the following light reflectance for surfaces in offices: ceilings, 80% or more; floors, 20%–40%; walls, 50%–70%; partitions, 40%–70%; and furniture, 25%–45% (IESNA 2000).
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3.2.1.4 Building Design Intention and Description The lighting systems at the Cambria building were evaluated to determine the illuminance distribution delivered by the lighting design and to determine the energy performance. The goals of the monitoring plan were the following:
1. Quantitatively assess the illumination distribution. 2. Determine the energy savings due to the lighting design without daylighting controls. 3. Determine the amount of electric lighting offset by daylighting and the energy saved in lighting. 4. Analyze the operation of the daylighting design and optimize its performance. 5. Document successes and weakness of the lighting design.
Figure 14: Outdoor Illuminance for July 13-16, 2001:
3.2.1.4 Illuminance Measurements Methodology Firstly, they monitored the outdoor and indoor illumination levels continuously from Friday to Monday. Figure 12 shows the outdoor illuminance. The first three days were mostly sunny with occasional cumulus clouds, and the final day was cloudy in the morning with some clearing by the afternoon.
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The indoor light levels were measured on the working surfaces in cubicles along a north-south cross section in the first-floor, southwest quadrant and the second-floor, southwest and northwest quadrants. On the first floor, three photometers were placed in each cubicle—one in front of the keyboard and one on the working surfaces on either side of the cubicle. The three photometers in front of the keyboards were 3.0, 5.5, and 7.9m from the inside surface of the outside wall. On the second floor, two photometers were placed in each cubicle—one in front of the keyboard and one on the working surface to the left of the keyboard. The photometers in front of the keyboards were again 3.0, 5.5, and 7.9 m from the inside surface of the outside wall.
The recommended minimum illuminance level on a horizontal surface for open offices is 30 to 50 fc (300 to 500 lux), depending on the task (IESNA 2000). For general reading of handwriting with a pen or printed materials in 8–10 point font, the recommended minimum illuminance is 30 fc (300 lux). For reading lighter copies or smaller fonts, the recommended minimum illuminance is 50 fc (500 lux).
Measured illuminance levels in the first-floor office area are shown in Figure 13. The ambient electric lights were on Friday and Monday during working hours and Friday evening for testing. The task lights were off in the cubicles 5.5 and 7.9 m from the south wall, and they were on for part of the testing period in the cubicle 3.0 m from the south wall. The ambient electric lights provided 25–35 fc (250–350 lux) on the working planes. The natural light added 10 fc (100 lux) at the cubicle closest to the outside wall to 3 fc (30 lux) at the cubicle furthest from the outside wall. These light levels are at the minimum levels for working at a computer terminal and performing easy reading tasks; however, some individuals prefer more light for reading. The task lights raise the light levels on the side working surfaces to 60–100 fc (600–1,000 lux). Figure 14 shows the lighting conditions near midday on June 7, 2001, which had similar sky conditions to those during the illuminance measurements. The reflected light from the light shelves only penetrates approximately 1 m along the ceiling. The light shelves are not effective because of the small amount of glass area (the wide window frames block much of the light), low reflectance off the light shelves, and the high angle of the summer sun. There was no useful daylighting due to lack of dimming the electric lighting in the first-floor office area during this testing period.
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Figure 15: Illuminance measurements at workstations for the first floor; southwest office area from July 13-16, 2001 (task lights used in cuble 10 ft from outside wall)
Figure 16: Southwest and Northwest office area
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The measured illuminance for the second-floor, southwest and northwest office areas is shown in Figures 15 and 16. The task lights were off except in the cubicle that is 5.5 m from the north wall in the northwest office area. The electric lights were off over the weekend, except for the period between 5:30 a.m. and 9:00 a.m. on Saturday in the northwest office area. The natural light levels on the north side were slightly reduced because the east half of the clerestory sun shades was in the down position for maintenance. The light levels with daylighting and the ambient electric lights are below the recommended minimum levels in all the areas except for the cubicles on the south side that are 10 and 26 ft (3.0 and 7.9 m) away from the outside wall. Therefore, task lighting would probably be used to increase the illuminance on the working surfaces. Illuminance from the ambient electric lights was measured Friday evening between 9:00 p.m. and 10:00 p.m. Illuminance levels at the workstations with only the ambient electric lights were approximately 15 fc (150 lux). This is lower than the first floor because the indirect luminaires do not reflect well off the high ceiling with trusses. The combination of the ambient electric lights and daylighting provided 20–40 fc (200–400 lux) at midday. The natural light levels over the weekend were 10–25 fc (100–250 lux) on the working surfaces and 20–30 fc (200–300 lux) in the open circulation areas. The daylighting on the second floor is reduced because of the poor reflection off the high ceiling, blockage by the roof trusses, the dark floor, and the windows on the outside walls are too low to provide light beyond the first row of cubicles. The illuminance levels on the second floor could be improved with direct lighting luminaires.
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Figure 17: Illuminance measurements at workstations for the second floor; southwest office area from July 13-16, 2001 (no task lighting)
Figure 18: Daylighting measurements at workstations for the second floor; northwest office area on July 13-16, 2001 (task lights used in cubicles 18 ft from outside wall)
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Figure 19: Northwest Office area near mid-day
The picture above shows the lighting conditions in the northwest office area near midday with the ambient electric lights on. The light distribution is fairly even as expected from the illuminance measurements. The ceiling is bright near the clerestory windows and has a darker area in the middle. The south-facing clerestory windows can be the source of undesirable lighting conditions at times. At low sun angles, they can admit direct beam radiation, and they can be very bright at other times, causing contrast and glare problems. Automatic sunshades are installed on the interior of the windows to block the direct beam radiation. The sunshades are controlled by an exterior photosensor. The sunshades block an excessive amount of light and defeat the purpose of the clerestory windows. Other options for these windows are to diffuse the incoming light with frosted or patterned glass or a light-diffusing film on the glass or direct the beam radiation to the ceiling with a louver system. The drawback of these solutions is the view of the sky will be lost.
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3.2.1.5
Best Practices for High Performance Buildings
Integrate daylighting into the envelope and lighting systems. Controlling the electric lighting when daylighting is available works in all climates and in almost any type of building. A good daylighting design should result from an integrated design process. The daylighting system has to be integrated with the envelope and trade-offs with heating and cooling understood to maximize whole-building energy savings. Use the following best practices to integrate daylighting with the lighting systems: a. Design daylighting into all occupied zones adjacent to an exterior wall or ceiling. b. Provide integral glare mitigation techniques in the initial design. c. Provide automatic, continuously dimming daylighting controls for all daylit zones. d. Design interiors to maximize daylighting distribution (no dark surfaces). e. Integrate the electrical lights with the daylighting system. f. Commission and verify post occupancy energy savings.
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3.2.2
Menil Collection
3.2.2.1 Introduction to the Building The Menil Collection, located in Houston, Texas, USA significantly valued the importance of natural light in its design, the gallery lit with natural light by application of two main feature, sky light and double paneled glass roof structure. Study of the building focused on ascertaining the balance between natural and artificial light. In particular, whether natural light was used to illuminate artwork or whether its primary purpose was providing a pleasant overall ambience. How the lighting was perceived by visitors, and how it compared to other naturally lit galleries has been considered as well. Synthesis of both lighting, natural and artificial has been applied rather than split arrangement with zones of natural light and zones of artificial light. Natural light is permitted but tempered with shading and louvered systems allowing the light to be expressed as rare and beautiful architectural element.
3.2.2.2 Analysis of Spaces
Sky may be glimpsed between louvers; some direct sun enters at certain times of day
Light fixtures are integrated into louvers
South edge of louvers is very bright, imposing a grain of light by their geometry.
Interior partitions cause shadow and dark pockets
Extra roof shading added in some areas to protect light sensitive works
Artwork not lit by natural light
The amount of lighting fixtures does not vary much between galleries that use natural light and those that do not. In each case, low-wattage spotlights illuminate and direct the viewer’s gaze to the works of art. Some work is displayed in lighted boxes, and these are much more frequent in the solid-roofed galleries. The areas with highest level of light level were the glass.
Figure 21: Lighting Analysis Diagram of Menil Collection
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3.2.2.3
Conclusion
Table 2: Percentage of artificial and natural light:
Menil Collection is perceived as a building flooded with natural light, with art illuminated primarily by the sun. In reality, artwork is lit by spotlight, and almost 40 percent of the museum’s galleries do not admit any sunlight at all because the art in those galleries is too delicate. In both solid-roofed and glass-roofed galleries, the number of spotlights is the same. Clearly, artificial light illuminates the artwork. Natural light, on the other hand, serves an aesthetic purpose--brightening certain parts of the museum, offering a glimpse of the sky and casting shadows.
There are a number of reasons why it would be difficult to rely on natural light in this museum:
The light comes in from one direction, making it hard to display art on all four walls without additional lighting.
Direct sunlight would damage art.
Lighting requirements differ for each piece of art--a matter of fine-tuning that can’t be accommodated by the roof system. For example, one exhibit of works on paper required that make shift shading be placed above the louver system. A roof system designed for one exhibitor for specific artworks would prohibit works from being moved from one place to another. In other words, it is easier to redirect spotlights than to change the roof system for each show. The impression that the museum is completely naturally lit is perhaps more important in this case than the reality.
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3.3
Site Study
3.3.1
Zoning of Spaces X
Y
Y
Z
Z
X
Figure 22: Zoning of First Floor of CORE Design Gallery
Zone 1
: Office Storage Room
Zone 2
: Office/ Meeting Room
Zone 3
: Powder Room
Zone 4
: Washroom
Zone 5
: Storage Room
Zone 6
: Corridor
Zone 7
: Gallery
Page | 30
Figure 23: Section X
The above cross-section illustrates a comparison of the types of lighting that is being employed for the office storage room, the office and the first floor gallery area. The office area however employs two types of lighting which are pendant lighting for general purpose illumination as well as spotlighting to highlight the artwork that is being displayed on the walls in the room unlike that in the storage room. Similarly, the gallery space employs a similar lighting approach though it is pre-dominantly illuminated using spotlights given the number of paintings that are exhibited within the space. LED spotlight bulbs are used so as to reduce the amount of heat and abrasive lighting that is casted on these paintings.
Figure 24: Section Y
The above section indicates similar lighting equipments for the office, powder room, washroom and storage area. These areas employ pendant lightings to provide uniform general space lighting within these spaces.
Page | 31
Figure 25: Section Z
The first floor gallery space is dominantly illuminated with spotlights that are directed towards the artworks that are exhibited. Our observations also indicate the concentration of activities in areas where these spotlights are directed. Apart from these spotlights, sunlight is also able to permeate indirectly into this space. Given the gallery’s sloping roofline, clerestories allow sunlight to permeate into this space.
Page | 32
3.3.2
Tabulation of Data
The colours used in the table correspond with their respective zone colour. The following readings were taken at a level of 1m and 1.5m from the ground as indicated.
Grid A8 A9 B5 B6 B7 B8 B9 C5 C6 C7 C8 C9 D5 D6 D7 D8 D9 E5 E6 E7 E8 E9 F5 F6 F7 F8 F9 D1 D2 E1 E2 D3 E3 D4 E4
Height 1m 1.5m 90 198 90 198 63 26 50 172 17 43 6 6 4 6 90 20 54 23 9 10 20 14 6 7 54 33 18 15 13 15 10 13 9 11 35 31 25 62 89 59 60 265 12 25 104 123 103 148 35 28 163 96 85 102 241 168 164 121 76 54 70 44 111 61 74 51 1074 709 440 151
Light Data (Lux) Peak Height Grid 1.5m 1m F1 201 242 F2 64 66 F3 62 53 F4 54 54 G1 68 71 G2 57 88 G3 88 99 G4 123 173 G5 81 90 G6 91 207 G7 92 176 G8 202 196 H1 26 29 H2 56 57 H3 66 37 H4 58 42 H5 52 34 H6 57 55 H7 81 86 H8 144 54 I1 111 292 I2 49 53 I3 50 55 I4 50 46 I5 186 101 I6 484 124 I7 78 83 I8 775 728 J1 46 51 J2 46 51 J3 46 46 J4 45 47 J5 50 53 J6 48 54 J7 58 60 Table 3: Light Data during Peak
Grid J8 K1 K2 K3 K4 K5 K6 K7 K8 K9 L1 L2 L3 L4 L5 L6 L7 L8 L9
Height 1m 1.5m 58 48 49 49 55 59 79 102 114 148 109 133 128 175 76 101 736 904 732 1156 71 46 340 143 1210 570 306 99 373 218 190 135 414 290 768 1265 1246 227
Grid A8 A9 B5 B6 B7 B8 B9 C5 C6 C7 C8 C9 D5 D6 D7 D8 D9 E5 E6 E7 E8 E9 F5 F6 F7 F8 F9 D1 D2 E1 E2 D3 E3 D4 E4
Height 1m 1.5m 85 197 84 198 7 7 6 6 5 6 5 5 4 5 7 7 6 6 5 6 5 5 5 5 6 6 5 6 5 6 5 5 5 5 6 6 5 6 5 6 5 5 5 5 5 5 4 4 4 4 3 4 3 4 4 4 3 4 4 5 17 8 111 61 108 60 1074 709 440 151
Light Data (Lux) Non Peak Height Grid 1.5m 1m F1 34 36 F2 36 39 F3 37 41 F4 39 44 G1 35 38 G2 36 41 G3 37 39 G4 39 41 G5 38 42 G6 38 41 G7 37 40 G8 38 41 H1 20 25 H2 29 35 H3 39 42 H4 40 43 H5 42 42 H6 41 42 H7 41 43 H8 40 42 I1 13 20 I2 26 24 I3 25 24 I4 26 23 I5 25 21 I6 27 22 I7 28 24 I8 27 24 J1 14 19 J2 30 26 J3 29 26 J4 31 28 J5 35 30 J6 36 33 J7 31 29
Grid J8 K1 K2 K3 K4 K5 K6 K7 K8 K9 L1 L2 L3 L4 L5 L6 L7 L8 L9
Height 1m 1.5m 37 33 20 26 25 29 28 31 33 49 39 57 41 59 41 59 735 904 734 1155 26 31 28 34 42 61 40 58 41 59 42 61 40 60 766 1259 1247 225
Legend Store (Office) Office Store Washroom Powder Room Corridor Gallery
Table 4: Light Data during Non-Peak
Page | 33
Based on the lighting data table above, the following observations were noted along with relevant discussions.
Observation 1: Light data collected during peak hours are lower compared to the data collected during nonpeak hours. Discussion 1: This is due to the fact that the peak hours for events occur during the night, therefore there is no daylighting contributing to the light readings. The increase in occupants during peak hours also results in more shadows which diffuse the overall light levels.
Observation 2: Light data collected at a level of 1.5m above ground are higher than the readings taken at 1m from the ground Discussion 2: This is due to the proximity of the lux meter to the artificial light source. At 1.5m, the lux meter is closer to the artificial light source, thus receiving a higher amount of light. However, the large difference in readings only occurs in grids which have artificial lightings.
Observation 3: Light data collected in grid D4 are significantly higher than those collected in the rest of the grids Discussion 3: Grid D4 is located in the Powder Room. The floor area of this zone is small yet has a large concentration of artificial light. This results in a higher reading on the lux meter.
Page | 34
3.3.3
Daylight Factor Analysis
3.3.3.1 Daylight Factor Calculations based on Zoning
Time / Date / Sky Condition
Zone
Daylight level in Malaysia,
Eo (lux)
Average Lux Reading based on collected data,
Daylight factor, DF DF = ( Ei / Eo) / 100%
Ei (lux) Office Storage Room DF = (Ei / Eo) x 100% 1
141
= ( 141 / 32000 ) x 100% = 0.44 %
Office / Meeting Room DF = (Ei / Eo) x 100% 2
5.22
= ( 5.22 / 32000 ) x 100% = 0.07 %
1pm 17th Sept
Powder Room
32000
Sunny DF = (Ei / Eo) x 100% 3
593.5
= ( 593.5 / 32000 ) x 100% = 1.85 %
Washroom DF = (Ei / Eo) x 100% 4
85
= ( 85 / 32000 ) x 100% = 0.27 %
Page | 35
Time / Date / Sky Condition
Zone
Daylight level in Malaysia,
Eo (lux)
Average Lux Reading based on collected data,
Daylight factor, DF DF = ( Ei / Eo) / 100%
Ei (lux) Storage Room DF = (Ei / Eo) x 100% 5
6.13
= ( 6.13 / 32000 ) x 100% = 0.02 %
Corridor DF = (Ei / Eo) x 100%
1pm 17th Sept
6
32000
38.25
= ( 38.25 / 32000 ) x 100% = 0.12 %
Sunny
Gallery DF = (Ei / Eo) x 100% 7
102.58
= ( 102.58 / 32000 ) x 100% = 0.32 %
Page | 36
3.3.3.2 Ecotect Daylight Simulation
Figure 26: Light Analysis Diagram for Daylight
Based on the calculations, Zone 3 (Powder Room) is the only zone that has a DF of more than 1%, which is considered a zone with fair daylight distribution.However, the rest have DF ranged between 0.02 - 0.44%, which means these zones have insufficient daylight. Therefore,
artificial
lightings
are
used
to
light
up
these
areas.
Page | 37
3.3.4
Types and Specifications of Lighting Used
Product Brand Lamp Luminous Flux EM Rated Colour Temperature Color Rendering Index Beam Angle Voltage Bulb Finish Placement
Product Brand
Philips Master LED Spotlight PAR 900Lm 2700K 80 25D 220-240V Ceiling Spotlight
Lamp Luminous Flux EM Rated Colour Temperature Color Rendering Index Beam Angle Voltage Bulb Finish Placement
Phillips T8 TL-D Standard Colours 1200Lm 4100K 63Ra8 59V Frosted Ceiling
Product Brand Lamp Luminous Flux EM Rated Colour Temperature Color Rendering Index Beam Angle Voltage Bulb Finish Placement
LEDARE Led Bulb E27 400Lm 2700K 80 220-240V Opal White Pendant Lighting
Product Brand Lamp Luminous Flux EM Rated Colour Temperature Color Rendering Index Beam Angle Voltage Bulb Finish Placement
Product Brand Luminous Intensity Rated Colour Temperature Color Rendering Index Beam Angle Voltage Bulb Finish Placement
Tornado Compact Fluorescent Spiral 1760Lm 6500K 220-240V White Pendant Lighting
Philips Essential MV MR16 Alu GU10 300 (max) cd 2800K 100 Ra8 36D 240V Clear Ceiling Spotlight
Reflectance values (%) for ceiling, walls and working plane 80
80
70
70
70
70
50
50
30
30
0
50
50
50
50
50
30
30
10
30
10
0
30
10
30
20
10
10
10
10
10
10
0
0.60
0.39
0.37
0.39
0.38
0.37
0.33
0.33
0.31
0.33
0.30
0.29
0.80
0.46
0.44
0.46
0.44
0.43
0.39
0.39
0.37
0.39
0.36
0.35
1.00
0.52
0.48
0.51
0.50
0.48
0.44
0.44
0.42
0.44
0.41
0.40
1.25
0.57
0.52
0.56
0.54
0.52
0.49
0.48
0.46
0.48
0.46
0.45
1.50
0.61
0.55
0.60
0.57
0.55
0.52
0.51
0.49
0.51
0.49
0.48
2.00
0.66
0.59
0.65
0.62
0.59
0.57
0.26
0.54
0.26
0.54
0.52
2.50
0.70
0.62
0.68
0.64
0.61
0.59
0.58
0.57
0.58
0.56
0.55
3.00
0.72
0.63
0.70
0.66
0.63
0.61
0.60
0.59
0.60
0.58
0.57
4.00
0.75
0.65
0.73
0.68
0.64
0.63
0.62
0.61
0.62
0.60
0.59
5.00
0.76
0.66
0.74
0.69
0.65
0.64
0.63
0.62
0.63
0.61
0.60
Room Index K
Page | 38
3.3.5
Artificial Light Analysis
Page | 39
Zone 1: Office Storage Room Dimension of Room ( L x W )
3.43 x 1.5
Total Floor Area / A
5.15 m²
Type of lighting fixture
Fluorescent Lamp
Number of ligthing fixture / N
1
Lumen of lighting fixture / F (lux)
1200
Height of luminaire (m)
2.24
Height of work level (m)
0.8
Mounting height / H (hm)
1.44
Assumption of Reflectance value
Ceiling: Exposed zinc sheet with timber joist (0.7) Wall: Polished concrete (0.5) Floor: Concrete screed (0.2)
Room Index / RI (K)
(3.43x1.50) / (3.43+1.50) x 1.44
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
= 5.15 / 7.1 = 0.73
Utilisation Factor / UF 0.44 (Based on given utilization factor table) Maintenance Factor / MF
0.8
Standard Illuminance (lux)
100
Illuminance Level (lux)
1 x 1200 x 0.44 x 0.8 / 5.15
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??¸= đ??´
= 82.02
According to MS 1525, standard illuminance for store is 100 lux. Illuminance for Office Storage Room which is 82.02 lux does not meet the standard requirement.
Page | 40
Page | 41
Zone 2: Office / Meeting Room Dimension of Room ( L x W )
6.48 x 7.28
Total Floor Area / A
47.17 m²
Type of lighting fixture
LED Spotlight
E27 Light Bulb
Number of ligthing fixture / N
7
2
Lumen of lighting fixture / F (lux)
900
400
Height of luminaire (m)
2.38
3.4
Height of work level (m)
0.8
Mounting height / H (hm)
1.58
Assumption of Reflectance value
Ceiling: Concrete screed + Plaster finish (0.7)
2.6
Wall: Concrete with plaster finish + Brick (0.5) Floor: Concrete screed (0.2) Room Index / RI (K)
(6.48x7.28) / (6.48+7.28) x 1.58
(6.48x7.28) / (6.48+7.28) x 2.6
= 47.17 / 21.74
= 47.17 / 35.78
= 2.17
= 1.32
0.62
0.54
Maintenance Factor / MF
0.8
0.8
Standard Illuminance (lux)
300 - 400
Illuminance Level / E (lux)
7 x 900 x 0.62 x 0.8 / 47.17
2 x 400 x 0.54 x 0.8 / 47.17
= 66.25
= 7.33
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
Utilisation Factor / UF (Based on given utilization factor table)
đ??¸=
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??´
Total Illuminance = 66.25 + 7.33 = 73.58
According to MS 1525, standard illuminance for drawing office is 300 - 400 lux. Illuminance for Office / Meeting Room which is 73.58 lux does not meet the standard requirement.
Page | 42
Page | 43
Zone 3: Powder Room Dimension of Room ( L x W )
2.54 x 2.50
Total Floor Area / A
6.35 m²
Type of lighting fixture
E27 Light Bulb
Number of ligthing fixture / N
1
Lumen of lighting fixture / A (lux)
1200
Height of luminaire (m)
2.75
Height of work level (m)
0.8
Mounting height / H (hm)
1.95
Assumption of Reflectance value
Ceiling: Plaster finish (0.7) Wall: Concrete with plaster finish + polished concrete(0.5) Floor: Rough finished tile (0.03)
Room Index / RI (K)
(2.54x2.50) / (2.54+2.50) x 1.95
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
= 6.35 / 9.83 = 0.65
Utilisation Factor / UF 0.39 (Based on given utilization factor table) Maintenance Factor / MF
0.8
Standard Illuminance (lux)
100
Illuminance Level / E (lux)
1 x 1200 x 0.39 x 0.8 / 6.35
đ??¸=
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??´
= 58.96
According to MS 1525, standard illuminance for toilet is 100 lux. Illuminance for Powder Room which is 58.96 lux does not meet the standard requirement.
Page | 44
Page | 45
Zone 4: Washroom Dimension of Room ( L x W )
1.34 x 2.50
Total Floor Area / A
3.35 m²
Type of lighting fixture
Fluorescent Spiral
Number of ligthing fixture / N
1
Lumen of lighting fixture / A (lux)
1760
Height of luminaire (m)
2.9
Height of work level (m)
0.8
Mounting height / H (hm)
2.1
Assumption of Reflectance value
Ceiling: Plaster finish (0.7) Wall: Concrete with plaster finish (0.5) Floor: Concrete screed (0.2)
Room Index / RI (K)
(1.34x2.50) / (1.34+2.50) x 2.1
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
= 3.35 / 8.06 = 0.42
Utilisation Factor / UF 0.38 (Based on given utilization factor table) Maintenance Factor / MF
0.8
Standard Illuminance (lux)
100
Illuminance Level / E (lux)
1 x 1760 x 0.38 x 0.8 / 3.35
đ??¸=
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??´
= 159.71
According to MS 1525, standard illuminance for toilet is 100 lux. Illuminance for Washroom which is 159.71 lux meets the standard requirement.
Page | 46
Page | 47
Zone 5: Storage Room Dimension of Room ( L x W )
2.55 x 2.5
Total Floor Area / A
6.38 m²
Type of lighting fixture
E27 Light Bulb
Number of ligthing fixture / N
1
Lumen of lighting fixture / A (lux)
400
Height of luminaire (m)
2.73
Height of work level (m)
0.8
Mounting height / H (hm)
1.93
Reflection Factors
Ceiling: Plaster finish (0.8) Wall: Concrete with plaster finish (0.5) Floor: Concrete screed (0.3)
Room Index / RI (K)
(2.55x2.5) / (2.55+2.5) x 1.93
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
= 6.38 / 9.75 = 0.65
Utilisation Factor / UF 0.39 (Based on given utilization factor table) Maintenance Factor / MF
0.8
Standard Illuminance (lux)
100
Illuminance Level / E (lux)
1 x 400 x 0.39 x 0.8 / 6.38
đ??¸=
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??´
= 19.56
According to MS 1525, standard illuminance for store is 100 lux. Illuminance for Storage Room which is 19.56 lux does not meet the standard requirement.
Page | 48
Page | 49
Zone 6: Corridor Dimension of Room ( L x W )
6.67 x 1.77
Total Floor Area / A
11.81 m²
Type of lighting fixture
Fluorescent Spiral
E27 Light Bulb
Number of ligthing fixture / N
1
2
Lumen of lighting fixture / F (lux)
1760
400
Height of luminaire (m)
2.8
3.6
Height of work level (m)
0.8
Mounting height / H (hm)
2
Reflection Factors
Ceiling: Plaster finish (0.8)
2.8
Wall: Concrete with plaster finish (0.5) Floor: Concrete screed (0.3) Room Index / RI (K)
(6.67x1.77) / (6.67+1.77) x 2.0
(6.67x1.77) / (6.67+1.77) x 2.8
= 11.81 / 16.88
= 11.81 / 23.63
= 0.70
= 0.50
0.46
0.39
Maintenance Factor / MF
0.8
0.8
Standard Illuminance (lux)
300
Illuminance Level / E (lux)
1 x 1760 x 0.46 x 0.8 / 11.81
2 x 400 x 0.39 x 0.8 / 11.81
= 54.84
= 21.13
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
Utilisation Factor / UF (Based on given utilization factor table)
đ??¸=
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??´
Total Illuminance = 54.84 + 21.13 = 75.97
According to MS 1525, standard illuminance for gallery is 300 lux. Illuminance for Corridor which is 75.97 lux does not meet the standard requirement.
Page | 50
Page | 51
Zone 7: Gallery Dimension of Room ( L x W )
9.57 x 7.47
Total Floor Area / A
71.49 m²
Type of lighting fixture
LED Spotlight
Halogen Spotlight
Number of ligthing fixture / N
23
2
Lumen of lighting fixture / F (lux)
900
320
Height of luminaire (m)
2.39
2.27
Height of work level (m)
0.8
Mounting height / H (hm)
1.59
Reflection Factors
Ceiling: Plaster finish + Exposed timber truss (0.7)
1.47
Wall: Concrete with plaster finish + Brick (0.5) Floor: Concrete screed (0.2) Room Index / RI (K)
(9.57x7.47) / (9.57+7.47)x1.59
(9.57x7.47) / (9.57+7.47) x 1.47
= 71.49 / 27.09
= 71.49 / 25.05
= 2.69
= 2.85
0.62
0.66
Maintenance Factor / MF
0.8
0.8
Standard Illuminance (lux)
300
Illuminance Level / E (lux)
23 x 900 x 0.62 x 0.8 / 71.49
2 x 320 x 0.66 x 0.8 / 71.49
= 143.62
= 4.73
đ??żđ?‘Ľđ?‘Š
đ?‘…đ??ź = (đ??ż+đ?‘Š)
đ?‘Ľđ??ť
Utilisation Factor / UF (Based on given utilization factor table)
đ??¸=
đ?‘ đ?‘Ľ đ??š đ?‘Ľ đ?‘ˆđ??š đ?‘Ľ đ?‘€đ??š đ??´
Total Illuminance = 143.62 + 4.73 = 148.35
According to MS 1525, standard illuminance for gallery is 300 lux. Illuminance for Corridor which is 148.35 lux does not meet the standard requirement.
Page | 52
3.3.5.1 Lighting Analysis Diagram
Figure 27: Light Analysis Diagram for Artificial Lighting
The lighting analysis diagram illustrates how the type of luminaires that are employed within each space affect the light levels in each space. The dimly lit spaces through our observations support the light levels which we have gotten through this diagrammatic analysis
Page | 53
3.3.6
Analysis & Evaluation Space illumination for galleries require a generative thought process since the
artworks that are being displayed within these galleries requires directed illumination (spotlighting). From our observations on site, the first floor gallery area employs the use of spotlights not only to illuminate the artworks that are being put on display but also as general space illumination for human circulation. Unlike typical general space lighting such as pendant lighting or ceiling lighting that illuminates a particular space uniformly, spotlight illuminates only a spot in a room where the spotlight is pointed towards. As such, spaces in which these spotlights are not directed at are most often inadequately lit up. While some may argue that uniformly distributed lighting may detract oneself from the desired ambience of the gallery, the purpose of the use of spotlights is to cast light on only the artworks, thus, putting focus on these artworks and not be distracted by other elements that exist within the space. While the interiors of the gallery mostly rely on artificial lighting, the main gallery on the first floor still harnesses a significant amount of lighting to help illuminate the space. Sunlight that enters this space does not directly face the paintings that are being exhibited unlike that which is being shown in our precedent study. The Menil Collection building in Houston, Texas employs a design measure that harnesses natural sun lighting to illuminate its gallery spaces. This saw the deterioration of artwork quality that is exhibited due to direct sun lighting. Most of the lux readings on our site are below the lux requirements for each space due to directional lighting especially for the main spaces such as the gallery and office spaces. However, the office space should exhibit better illumination readings since productivity generally occurs within this space. As such, better artificial illumination should be employed to act as task lighting to help improve productivity within this space. The electric light levels diagram also indicate the poor illumination that occurs within these main spaces. By looking at the daylight factor simulation, natural lighting is able to penetrate to certain spaces such as the washroom and powder room which is located to the North of the gallery. The window that is located at the North part of the office also allows partial natural illumination of this space if the blinds are not employed. Overall, considerations have to be taken not only to illuminate and at the same time preserve the condition of the artworks that are being displayed in the gallery but also facilitate
circulation
within
the
space.
Page | 54
4.0 Acoustics 4.1
Literature Review Acoustics is the science of sound. It deals with the study of all mechanical waves in
gases,
liquids,
and
solids
including
topics
such
as
vibration, sound, ultrasound and infrasound. There are many kinds of sound and many ways that it affects our lives. We use sound to communicate and you might also know that acoustics is important for creating musical instruments or concert halls or surround sound stereo or hearing aids.
4.1.1
Architectural Acoustics Architectural acousticians study how to design buildings and other spaces that have
pleasing sound quality and safe sound levels. Architectural acoustics includes the design of concert halls, classrooms and even heating systems. Building acoustics is vital in attaining sound quality that is appropriate for the spaces within a building. From achieving a good buffer from the building's exterior envelope to the building's interior spaces, acoustic plays a vital role in realising the mood that is to be created in the spaces that reside within the building.
4.1.2
Sound Pressure Level Acoustic system design can be achieved through the study of sound pressure level.
(SPL). Sound Pressure Level is the average sound level at a space caused by a sound wave. Sound pressure in air can be measured with a microphone. SPL is a logarithmic measure of the effective sound pressure of a sound relative to a reference value. It is measured in decibels (dB) above a standard level. Sound pressure formula:
Page | 55
4.1.3
Reverberation Time Reverberation, in terms of psychoacoustics, is the interpretation of the persistence
of sound after a sound is produced. A reverberation, or reverb, is created when a sound or signal is reflected causing a large number of reflections to build up and then decay as the sound is absorbed by the surfaces of objects in the space – which could include furniture and people, and air. This is most noticeable when the sound source stops but the reflections continue,
decreasing
in amplitude,
until
they reach
zero
amplitude.
Reverberation is frequency dependent. The length of the decay, or reverberation time, receives special consideration in the architectural design of spaces which need to have specific reverberation times to achieve optimum performance for their intended activity.
Reverberation Time formula:
[Referenced from http://www.ssc.education.ed.ac.uk/courses/pictures/dmay1026.gif] Where, T is the reverberation time in seconds V is the room volume in m3 A is the absorption coefficient
Reverberation time is affected by the size of the space and the amount of reflective or absorptive surfaces within the space. A space with highly absorptive surfaces will absorb the sound and stop it from reflecting back into the space. This would yield a space with a short reverberation time. Reflective surfaces will reflect sound and will increase the reverberation time within a space. In general, larger spaces have longer reverberation times than smaller spaces. Therefore, a large space will require more absorption to achieve the same reverberation time as a smaller space.
Page | 56
Figure 28 : Reverberation Time Graph
The above diagram illustrates the reverberation time that is attributed to different rooms of different volumes with different specific functions.
4.1.4
Sound Reduction Index Sound reduction index is used to measure the level of sound insulation provided by a
structure such as a wall, window, door, or ventilator. The understanding of a sound reduction index is important to incorporate acoustic system design into a given space to decrease the possibility of sound from permeating from a loud space to a quiet space. Sound reduction index formula:
Where, SRI = Sound Reduction Index (dB); Wi = Sound power incident on one side of a sound barrier (W); and Wt = Sound power transmitted into the air on the side of the partition (W).
Page | 57
4.1.5
Issues of Acoustic System Design
Acoustic Comfort Acoustic comfort is essential to attain an adequate level of satisfaction and moral health amongst patrons that reside within the building. Indoor noise and outdoor noise are the two main aspects that contribute to acoustical comfort (or discomfort). Main contributors for indoor noise can generally be traced from human activity as well as machine operations. External noise includes noise from traffic or activities that occur outside of the building.
Acoustic and Productivity Spatial acoustics may contribute to productivity in a particular building. Inconducive acoustic environments may dampen productivity. Productivity also depends on the building’s functions as well as the type of patrons that occupy the building. “Acoustical comfort” is achieved when the workplace provides appropriate acoustical support for interaction, confidentiality, and concentrative work.” (GSA,2012). Spatial acoustics is of vital importance especially where workers’ productivity is being emphasized.
Impacts of Inappropriate Acoustics For certain spaces such as in a functional music setting, proper sound isolation helps create a musical “island” while inadequate sound isolation, imprisons musicians in an inhospitable, Alcatraz like setting. This thus is evident that improper acoustical measures may backfire if design measures are not implemented properly.
Acoustical Discomfort and Health Noise is an increasing public health problem according to the World Health Organization’s Guidelines for Community Noise. Noise can have the following adverse health effects: hearing loss; sleep disturbances; cardiovascular and psychophysiologic problems; performance reduction; annoyance responses; and adverse social behavior. As such, articulate measures have to be carried out so as to ensure that acoustical discomfort does not exist in spaces where human occupation is kept at prolonged hours.
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4.1.6
Acoustic Design for Galleries Acoustical design of interior spaces has two major concerns. The first issue comes in
the form of devising design strategies to isolate sound of galleries from exterior sources including atmospheric or man-made noises. Traffic noises or noise that is emitted from neighbouring buildings may interfere with the experience of the gallery space. The second major consideration of acoustical design is the room acoustics and related comfort parameters. Reverberation time is one major parameter that carries clues on the intelligibility and noise levels due to suspended sound within enclosed interior spaces which are sparsely furnished like those in art galleries. Selection of materials is of utmost importance in such spaces as factors such as reverberation times determine the selection criteria for materials. By drawing a relationship to buildings of a similar typology such as that of a museum, we are able to understand the
Table 5 : Acoustical Parameters and Recommended Ranges
For a public exhibition space where noise levels are often kept at a minimum, the above table illustrates the recommended reverberation time for spaces such as galleries and museums.
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4.2
Precedent Study
4.2.1
Introduction to the Building The auditorium of Y覺ld覺z Technical University (YTU), located in the central campus of
the YTU, is mainly used for congresses, symposium, conferences and various other ceremonies. From time to time, it also hosts events such as concerts. The hall was renovated in order to increase the audience capacity and eliminate some of its disadvantages, while preserving its general architectural characteristics. The distribution of the acoustic conditions throughout the space and the effects of the renovation on this distribution were determined by performing measurements at several audience locations in the hall. Acoustic measurements were performed in the hall before the renovation, on the unfurnished hall and after renovation. The results obtained from these three distinct situations were evaluated in order to show the impact of interior surface materials on the acoustic characteristics of the space.
Figure 30: The YTU auditorium (before renovation)
4.2.2
Figure 29: The YTU auditorium (after renovation)
Selection of Interior Surface Materials: The effects of materials with different acoustic absorption characteristics on the
acoustical environment are proportional to their surface areas. For this reason, the surface materials chosen to provide the optimum RT for the hall were also assessed with respect to their sizes. Cellular materials for high frequency voices and vibratory panels for low frequency voices were used to obtain a balanced frequency distribution. The reasons for choosing the materials used on the surfaces of the space are briefly explained below.
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4.2.2.1 Floors The audience platform of the auditorium was furnished with 4mm thickness of felt underlying a carpet of 8mm thickness. cloth upholstered chairs were preferred for the seating. In order to prevent a sound trap being formed on the stage, and to allow the sound rays to reach the audience in the most appropriate way, it was decided to use more reflective materials for the stage flooring, and so wood parquet on wood joists was preferred for these surfaces. 4.2.2.2 Ceilings 8mm thick gypsum boards were used, which also covered the air conditioning installation. The coffered ceiling was not wholly covered with wooden material and was partly left as a hard surface, in order to preserve the architectural characteristics of the structure and to prevent the volume, which was already reduced as a result of the increase in the height of the audience platform, being further reduced. in particular the" panelled surfaces" which could have been applied to the stage ceiling , were thought to be useful , but the paint on the concrete ceiling was maintained, since the height of the space excluded this option from consideration. The vertical wooden panels placed around the stage were used to try to meet the need for a reflective surface on and around the stage. 4.2.2.3 Walls 10mm thick, wooden panels is considered appropriate in terms of the acoustic parameters. Some fibre glass-based absorbing material was placed behind these panels in order to maintain the balance between high frequency and low frequency voices. The back wall of the hall was furnished with 10mm wooden panels, which were covered with thick fabrics, to prevent the generation of an echo. Pipes and canals for the air conditioning system were hidden by sloped panels covered with fabrics applied on gypsum, especially at the interface of the back wall and the ceiling.
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Table 6: Surface materials in auditorium, their surface area and absorption coefficient (based on Harris, 1994: Cavanaugh & Wilco, 1999)
4.2.3
Measurement and Analysis
During the renovation project, calculation and assessments were carried out on the RT, sound level and speech intelligibility parameters. Since 2/3 of the audience capacity of the space was assumed
to be utilized in the RT calculations, both empty and occupied seats
were included in the calculation at different absorption values. As speaking intended to be the main use of the hall, the optimum RT range was determined on the basis of the space volume and speech. The change in RTs calculated by taking the interior surface materials into consideration are shown in table 2. The RTs of the hall, which were measured before renovation, and the RTs obtained from the calculation performed for the empty hall are also included in table2.
Table 7: RTs of auditorium, before renovation (measured) and after renovation (calculated)
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4.2.4
Background Sound Level (BSL) Sound level measurements were carried out to find the effect of the interior surface
cladding of the space on the BSL.As can be seen in Table 3, in the unfurnished condition while the air conditioning was operating, the measurements were above the acceptable noise levels at all frequencies, When the air conditioning was turned off under the same conditions, the results were only about 1 dB over the acceptable values at frequencies of 1000 Hz, 2000 Hz and 4000 Hz. On the other hand, the BSLs were always below the acceptable limits in the furnished room, both before and after renovation.
Table 8: Measured and acceptable BSLs (air conditioning)
As can be seen in Table 4, by partially covering the ceiling with gypsum board and using wooden panels on the walls, significant decays were obtained for RTs at low frequencies after the renovation.
Table 9: Measured, calculated and optimum RTs of YTU auditorium for speech activities
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4.2.5
Early Decay Time (EDT) The measured EDT values of the auditorium and optimum EDT values derived from
the measured RT values are shown in Table 5. EDT values measured in furnished conditions (before and after renovation) the space were found to be within the optimum range at frequencies except 500 and 1000 Hz. It can be seen that the EDT values are slightly higher than the optimum values, but these small differences are almost certainly not audible. In general, when the EDT values are analyzed, it can be seen that a rather good distribution has been achieved in the auditorium.
Table 10: Measured and optimum EDTs of the YTU auditorium
4.2.6
Definition (D50) The D50 parameter, an important factor in speech intelligibility, was also measured
and assessed. As the D50 values, generally increased so the intelligibility of speech also improved. As can be seen in Table 6, only one receiver point (R3) was below the limit. When the acceptability limit is raised to 65% it can be seen that, prior to the renovation, none of the receiver points were adequate for intelligibility. On the other hand, after the renovation all the receiver points except R3 were above the 65% limit. It is obviously clear that the speech intelligibility was improved by the renovation
Table 11: D50 values of YTU auditorium
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Figure 31: Section of the YTU auditorium (after renovation)
Figure 32: Plan of YTU auditorium (after renovation)
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4.2.7
Speech Transmission Index (STI) The STI is also an indicator of the level of speech intelligibility. When the STI values,
which were measured at various audience the STI values varied between 0.36 and 0.43 in the unfurnished space. The STI values, which fluctuated in the range 0.52–0.62 in the hall before renovation, were increased to 0.68–0.74 after renovation. This increase was due to shortening the low frequency RT and adequate early reflections. Figure 28 includes a scale, which can be used to interpret the intelligibility
Figure 33: STI in YTU auditorium
Table 12: Measured STI values for unfurnished and furnished (before and after renovation) conditions of the YTU auditorium
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4.2.8
Total Sound Level (TSL)
Suitability of the TSL was checked in this part. A passage was spoken from the stage and the sound levels at the audience positions were measured at the same time. It was found that the sound levels varied in the range 58.5–64.5 dB before renovation and were in the range 59.0–63.0 dB after renovation. In order to maintain the intelligibility of speech, the sound level in a space with a BSL of 40 dBA must be at least about 60 dB (Cavanaugh & Wilkes, 1999).. However, it is clear that these sound levels are dependent on the speaker and can vary according to the conditions. In this study, only an example condition was evaluated. 4.2.9
Evaluation and Conclusion
The comparison of the acoustical parameters measured in the unfurnished and furnished hall (before and after renovation), and the optimum values given for these parameters are shown together in Table 8.. The change in the acoustic environment of the hall due to the use of surface materials can be clearly seen for all the acoustic parameters. Together with the renovation, the RT values were decreased to the optimum values by using suitable indoor surface materials.
Table 13: Room average measurement results and optimum values for acoustic parameters of the YTU auditorium. (*500-1000 Hz average)
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In this study, the change in the acoustic parameters, which was caused by the use of interior surface materials, was shown through measurements and assessments carried out for the unfurnished and furnished hall (before and after renovation). The differences determined between the three distinct conditions of the hall in terms of acoustic comfort obviously show the importance of interior surface material preferences in architecture. Within this context, the undeniable need for architects to consult acoustic engineers in order to determine the proper interior surface materials to be used for spaces designed by them (especially spaces for which auditory perception is significant), besides other design characteristics such as dimensions, shape, furnishing, should be emphasized.
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4.3
Site Study
4.3.1
Outdoor Noise Sources
Figure 34: Location of Site in relation to Main Road
Given our site’s close proximity to a main transport route which is Jalan Kemajuan Subang, most of the outdoor noise would originate from the vehicular activity that occurs along this route especially during peak hours. In addition to that, occasional vehicles that pass through the inner roads of SS15/2A also contribute to the vehicular noise which the building receives. Apart from vehicular noise, noise sourced from outdoor human activities also originates from nearby buildings such as the Mamak Food Outlet which is located East of the building as well as other houses and shop houses that are located around our site.
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4.3.2
Tabulation of Data The colours used in the table correspond with their respective zone colour. The following readings were taken at a level of 1m and 1.5m from the ground as indicated
Grid A8 A9 B5 B6 B7 B8 B9 C5 C6 C7 C8 C9 D5 D6 D7 D8 D9 E5 E6 E7 E8 E9 F5 F6 F7 F8 F9 D1 D2 E1 E2 D3 E3 D4 E4
Noise Level (dB) Peak Height Height Grid 1m 1m 46 F1 50 46 F2 50 51 F3 50 49 F4 52 50 G1 50 48 G2 51 49 G3 51 51 G4 52 52 G5 53 49 G6 53 49 G7 53 49 G8 53 53 H1 51 53 H2 52 52 H3 52 49 H4 51 49 H5 52 53 H6 53 53 H7 54 53 H8 54 52 I1 52 49 I2 53 54 I3 52 53 I4 52 52 I5 53 50 I6 50 49 I7 50 50 I8 67 50 J1 52 50 J2 53 50 J3 53 51 J4 52 50 J5 53 51 J6 51 50 J7 52
Grid J8 K1 K2 K3 K4 K5 K6 K7 K8 K9 L1 L2 L3 L4 L5 L6 L7 L8 L9
Table 14: Noise Level Data for Peak
Height 1m 61 56 56 59 59 59 59 61 68 68 56 56 59 59 59 56 55 67 69
Grid A8 A9 B5 B6 B7 B8 B9 C5 C6 C7 C8 C9 D5 D6 D7 D8 D9 E5 E6 E7 E8 E9 F5 F6 F7 F8 F9 D1 D2 E1 E2 D3 E3 D4 E4
Noise Level (dB) Non-Peak Height Grid Height 1m 1m 46 F1 56 46 F2 56 47 F3 56 47 F4 55 46 G1 56 46 G2 56 46 G3 56 52 G4 56 49 G5 56 47 G6 57 47 G7 57 47 G8 57 51 H1 56 50 H2 57 58 H3 56 57 H4 57 57 H5 59 50 H6 57 50 H7 57 50 H8 57 49 I1 57 47 I2 56 51 I3 56 52 I4 58 52 I5 59 52 I6 59 53 I7 61 51 I8 61 51 J1 57 52 J2 56 52 J3 56 54 J4 59 54 J5 58 54 J6 58 54 J7 61
Grid J8 K1 K2 K3 K4 K5 K6 K7 K8 K9 L1 L2 L3 L4 L5 L6 L7 L8 L9
Height 1m 52 53 53 53 51 51 53 53 67 67 53 53 52 53 54 56 55 67 69
Legend Store (Office) Office Store Washroom Powder Room Corridor Gallery
Table 15: Noise Level Data for Non-Peak
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Based on the noise level data table above, the following observations were noted along with relevant discussions.
Observation 1: The average noise level data collected during peak hours are higher compared to the data collected during non-peak hours. Discussion 1: There are a larger number of occupants in the building during peak hours which contributes to the noise levels. The speakers are also utilized during events, further adding to the noise levels.
Observation 2: Average noise levels recorded in the Office Storage Room does not differ from peak to non-peak hours. Discussion 2: The office store is located in an isolated corner of the building and is not accessible to guests, hence the noise levels remain the same.
Observation 3: The average noise level recorded in the gallery during peak hours is the highest reading. Discussion 3: The gallery is the main space during events; hence there is a higher concentration of occupants in this zone which contributes to the overall noise levels. The two speakers of the building are also located in this zone.
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4.3.3
Indoor Noise Sources
4.3.3.1 Air Circulators
Figure 35: Placement of Air Circulators
Air conditioners are used to circulate air within a confined space as well as cool down the air for a particular room. Air-conditioners are located in the office and gallery to create a conducive environment for both the staff and visitors of the gallery. To minimize electrical consumption, ceiling fans are also used as an alternative to circulate and cool down air within a particular space. During the operation of these two air circulators, a noticeable amount of noise is produced though not significant enough to induce an acoustical disturbance in that particular space.
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4.3.3.2 Human Activity
Figure 36: Nodes of Human Activity
Concentration of human activities especially during peak hours occurs in the gallery space as illustrated in the diagram. Visitors interacting with the staff members about the artworks that are displayed within the gallery will be the main noise contributor to this space. Secondary noise contributors within our site include the office space when the staff members interact with one another.
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4.3.3.3 Speakers
Figure 37: Placement of Speakers
These speakers are located at two positions that face the central gallery on the first floor. They are usually turned on whenever there are visitors in the gallery. Volume is kept to a minimum to create a favorable ambience and serve as background music while visitors observe the different artworks that are being displayed. During non-peak hours, these speakers are not being used.
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4.3.3.3 Acoustic Rays Diagram
Figure 38: Acoustic Ray Diagram (from Speakers)
The above diagram indicates the acoustic rays imposed by the position of the two satellite speakers. The two red dots indicate the positions for each of the speakers and its suggested noise path when the speakers are in operation. From the diagram we can also observe that these acoustic rays bounce of the glass faรงade that is directly opposite these speakers. The concentration of the bouncing of rays appears to be more highly concentrated to the west of the plan where the spatial area is much lower when compared to the main gallery space at the centre. Also it can be observed that these rays are mostly contained within the first floor gallery space with only a few rays permeating into the corridor space that leads to the office area.
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4.3.4
Calculation of Sound Pressure Level To obtain the sound pressure level measurement of main noise sources in order to
establish the noise decibel produced by each noise source.
4.3.4.1 Calculations for Speakers
Using SPL = 10log (I1/I0) Where I1 = Sound Power (watts) I0 = Reference Power 1.0 X 10ˆ-12
Number of speakers in Core Gallery = 2 One speaker produces approximately 80dB Therefore, SPL
= 10log(I1/L0)
80
= 10log(I1/L0)
log-1(80/10) = I1/(1.0 X 10ˆ-12) I1 = log-1(80/10) X (1.0 X 10ˆ-12) I1 = 1.0 X 10ˆ-4 W
Total Number of Speakers = 2 Total Intensity = 2 X 1.0 X 10ˆ-4 = 2.0 X 10ˆ-4 W
Therefore, Combined SPL
= 10 log(I1/I0) = 10 log(2.0 X 10ˆ-4 / 1.0 X 10ˆ-12) = 83.01dB
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4.3.4.2 Calculations for Air Conditioners
One air conditioner produces approximately 50dB SPL
= 10log(I1/I0)
50
= 10log(I1/I0)
log-1(50/10) = I1/(1.0 X 10ˆ-12) I1 = log-1(50/10) X (1.0 X 10ˆ-12)) I1 = 1.0 X 10ˆ-7 W
Total number of air conditioners = 5 Total Intensity = 5 X 1.0 X 10ˆ-7 = 5.0 X 10ˆ-7 W
Therefore, Combined SPL
= 10 log(I1/I0) = 10 log(5.0 X 10ˆ-7 / 1.0 X 10ˆ-12) = 56.99dB
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4.3.4.3 Calculations for Ceiling Fans
One ceiling fan produces approximately 50dB SPL
= 10log(I1/I0)
50
= 10log(I1/I0)
log-1(50/10) = I1/(1.0 X 10ˆ-12) I1 = log-1(50/10) X (1.0 X 10ˆ-12)) I1 = 1.0 X 10ˆ-7 W
Total number of air conditioners = 6 Total Intensity = 6 X 1.0 X 10ˆ-7 = 6.0 X 10ˆ-7 W
Therefore, Combined SPL
= 10 log(I1/I0) = 10 log(6.0 X 10ˆ-7 / 1.0 X 10ˆ-12) = 57.78dB
To calculate total noise produced by noise sources in a particular zone: Total Intensity = Number of Speakers X (1.0 X 10ˆ-4) + Number of Air Conditioners X (1.0 X 10ˆ-7 ) + Number of Ceiling Fans X (1.0 X 10ˆ-7) =Z Where, 1.0 X 10ˆ-4 W is Intensity of 1 Speaker 1.0 X 10ˆ-7 W is Intensity of 1 Air Conditioner 1.0 X 10ˆ-7 W is Intensity of 1 Ceiling Fan
Using SPL
= 10log (Z / 1.0 X 10ˆ-12) = Answer in dB Page | 78
4.3.5
Zoning of Spaces
Figure 39: Zoning of CORE Design Gallery (for Acoustic analysis)
Zone 1
: Office/ Meeting Room
Zone 2
: Powder Room
Zone 3
: Storage Room
Zone 4
: Corridor
Zone 5
: Gallery
Grey Zones
: Areas without equipment
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4.3.5.1 Location of Equipment
Page | 80
4.3.5.1 Equipment Specifications
Product Brand Weight Power Consumption Frequency Response Dimensions (Indoor Unit) Cooling Operation Placement Product Brand
Daikin Inverter 1.0 Hp Air Conditioner 14kg 570 – 710W 39-45dB 305 x 890 x 209 10°C to 43°C Wall
Weight Power Consumption Frequency Response Indoor Fan Speed Dimensions (Indoor Unit) Cooling Operation Placement
Panasonic 1.0 Hp Air Conditioner CS-SC9QKH 8kg 570 – 710W 39-45dB 700-1220 Rpm 290 X 870 X 199 10°C to 43°C Wall
Product Brand Fan Width Power Consumption Color Indoor Fan Speed No. of Blades
Alpha Fan Model 838 3B 56” 30 – 90W Black and White 100 - 250 Rpm 3
Product Brand Fan Width Power Consumption Color Indoor Fan Speed No. of Blades
Alpha Fan Model 318 5B 40” 20 – 80W White 120 - 270 Rpm 5
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Weight Frequency Response
BOWERS & WILKINS – 6 ½” 2 WAY Bookshelf Speakers 7kg 49Hz – 22Hz
Amplification Power
30 – 100W
Product Brand
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4.3.6
Calculation of Sound Pressure Levels
Zone 1 (Office/ Meeting Room)
Where, 1.0 X 10ˆ-7 W is Intensity of 1 Air Conditioner
2 X Air Conditioners and 2 X Ceiling Fans
1.0 X 10ˆ-7 W is Intensity of 1 Ceiling Fan
Total Intensities = (2 X 1.0 X 10ˆ-7) + (2 X 1.0 X 10ˆ-7) = 4.0 X 10ˆ-7 W
Using SPL
= 10log (4.0 X 10ˆ-7 / 1.0 X 10ˆ-12) = 56.02dB
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Zone 2 (Powder Room)
Where, 1.0 X 10ˆ-7 W is Intensity of 1 Ceiling Fan
1 X Ceiling Fan Total Intensity
Using SPL
= 10log (1.0 X 10ˆ-7 / 1.0 X 10ˆ-12) = 50dB
= (1 X 1.0 X 10ˆ-7) = 1.0 X 10ˆ-7 W
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Zone 3 (Storage Room)
Where, 1.0 X 10ˆ-7 W is Intensity of 1 Air Conditioner
1 X Air Conditioner and 1 X Ceiling Fan
1.0 X 10ˆ-7 W is Intensity of 1 Ceiling Fan
Total Intensities = (1 X 1.0 X 10ˆ-7) + (1 X 1.0 X 10ˆ-7) = 2.0 X 10ˆ-7 W
Using SPL
= 10log (2.0 X 10ˆ-7 / 1.0 X 10ˆ-12) = 53.01dB
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Zone 4 (Corridor)
Where, 1.0 X 10ˆ-4 W is Intensity of 1 Speaker
2 X Speakers Total Intensity = (1 X 1.0 X 10ˆ-4)
Using SPL
= 10log (1.0 X 10ˆ-4 / 1.0 X 10ˆ-12) = 80dB
= 1.0 X 10ˆ-4 W
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Zone 5 (Gallery)
Where, 1.0 X 10ˆ-4 W is Intensity of 1 Speaker
2 X Speakers, 2 X Air Conditioners and 2 X Ceiling Fans
1.0 X 10ˆ-7 W is Intensity of 1 Ceiling Fan
Total Intensities
1.0 X 10ˆ-7 W is Intensity of 1 Air Conditioner
= (2 X 1.0 X 10ˆ-4) + (2 X 1.0 X 10ˆ-7) + (2 X 1.0 X 10ˆ-7) = 2.0 X 10ˆ-4
Using SPL
= 10log (2.0 X 10ˆ-4 / 1.0 X 10ˆ-12) = 83.01dB
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4.3.7
Tabulation of Sound Pressure Levels
Following is the data produced by speakers, air conditioners and ceiling fans that are established as main noise sources for different zones on the first floor level of Core Gallery.
ZONE
SOUND PRESSURE LEVEL (dB)
1. Office/ Meeting Room
56.02
2. Powder Room
50.00
3. Storage Room
53.01
4. Corridor
80.00
5. Gallery
83.01
Table 16: Sound Environments with their corresponding Sound Pressure Levels (Sourced from http://trace.wisc.edu/docs/2004-About-dB/)
Page | 88
4.3.8
Analysis With reference to the table of general sound environments, the office area, prayer
room and storage room falls under the category of 50-59dB which is considered to be ½ as loud as an ordinary conversation which is a definitely desired acoustic trait for the private rooms of a gallery space where productivity mostly occurs especially in the office. The corridor leading to the staircase area as well as the first floor gallery area falls under the category between 80-89dB which is 4 times louder than an ordinary conversation. However, in the case of the core gallery most of this sound pressure level is attributed to the speakers that are being employed during peak hours to act as a background music for the gallery during an event.
4.3.9
Conclusion Whilst it is suitable to have normal conversations in the office area since it marks a
sound pressure level of only 50-59dB which is approximately ½ as loud as an ordinary conversation, the gallery which establishes a sound pressure level of 80-89dB indicates that normal conversations are not suitable to be held in such an area. However, since it is a gallery, conversations are usually kept to a minimum. The use of speakers for background music is probably an attempt to mask any conversations that take place between patrons of the gallery.
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4.3.10 Spaces Acoustic Analysis
ZONE 1: OFFICE/ MEETING ROOM Non-Peak Hour Highest Reading: 53dB
Lowest Reading: 46dB
53 = 10log(I1/I0)
46 = 10log(I1/I0)
53 = 10log(I1/1.0X10ˆ-12)
46 = 10log(I1/1.0X10ˆ-12)
log-153/10 = I1/(1.0X10ˆ-12)
log-146/10 = I1/(1.0X10ˆ-12)
2.0 X 10ˆ5 = I1/(1.0X10ˆ-12)
3.98 X 10ˆ4 = I1 / (1.0 X 10ˆ-12)
I1 = 2.0 X 10ˆ-7
I1 = 3.98 X 10ˆ-8 W
Total Intensities, I = (2.0 X 10ˆ-7) + (3.98 X 10ˆ-8) = 2.34 X 10ˆ-7 SPL
= 10 log(I1/I0) = 10 log(2.34 X 10ˆ-7 / 1.0 X 10ˆ-12) = 53.69dB at Zone 1, Office/ Meeting Room during non-peak hour
Peak Hour Highest Reading: 53dB
Lowest Reading: 46dB
54 = 10log(I1/I0)
49 = 10log(I1/I0)
54 = 10log(I1/1.0X10ˆ-12)
49 = 10log(I1/1.0X10ˆ-12)
log-154/10 = I1/(1.0X10ˆ-12)
log-149/10 = I1/(1.0X10ˆ-12)
2.51 X 10ˆ5 = I1/(1.0X10ˆ-12)
7.94 X 10ˆ4 = I1 / (1.0 X 10ˆ-12)
I1 = 2.51 X 10ˆ-7
I1 = 7.94 X 10ˆ-8 W
Total Intensities, I = (2.51 X 10ˆ-7) + (7.94 X 10ˆ-8) = 3.30 X 10ˆ-7 SPL
= 10 log(I1/I0) = 10 log(3.30 X 10ˆ-7 / 1.0 X 10ˆ-12) = 55.19dB at Zone 1, Office/ Meeting Room during peak hour
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ZONE 4, CORRIDOR Non-Peak Hour Highest Reading: 52dB
Lowest Reading: 50dB
52 = 10log(I1/I0)
50 = 10log(I1/I0)
52 = 10log(I1/1.0X10ˆ-12)
50 = 10log(I1/1.0X10ˆ-12)
log-152/10 = I1/(1.0X10ˆ-12)
log-150/10 = I1/(1.0X10ˆ-12)
1.58 X 10ˆ5 = I1/(1.0X10ˆ-12)
1.0 X 10ˆ5 = I1 / (1.0 X 10ˆ-12)
I1 = 1.58 X 10ˆ-7 W
I1 = 1.0 X 10ˆ-7 W
Total Intensities, I = (1.58 X 10ˆ-7) + (1.0 X 10ˆ-7) = 2.58 X 10ˆ-7 SPL
= 10 log(I1/I0) = 10 log(1.58 X 10ˆ-7 / 1.0 X 10ˆ-12) = 54.12dB at Zone 4, Corridor during non-peak hour
Peak Hour Highest Reading: 56dB
Lowest Reading: 52dB
56 = 10log(I1/I0)
52 = 10log(I1/I0)
56 = 10log(I1/1.0X10ˆ-12)
52 = 10log(I1/1.0X10ˆ-12)
log-156/10 = I1/(1.0X10ˆ-12)
log-152/10 = I1/(1.0X10ˆ-12)
3.98 X 10ˆ5 = I1/(1.0X10ˆ-12)
1.58 X 10ˆ5 = I1 / (1.0 X 10ˆ-12)
I1 = 3.98 X 10ˆ-7 W
I1 = 1.58 X 10ˆ-7 W
Total Intensities, I = (3.98 X 10ˆ-7) + (1.58 X 10ˆ-7) = 5.56 X 10ˆ-7 SPL
= 10 log(I1/I0) = 10 log(5.56 X 10ˆ-7 / 1.0 X 10ˆ-12) = 57.45dB at Zone 4,Corridor during peak hour
Page | 91
ZONE 5, GALLERY Non-Peak Hour Highest Reading: 56dB
Lowest Reading: 49dB
56 = 10log(I1/I0)
49 = 10log(I1/I0)
56 = 10log(I1/1.0X10ˆ-12)
49 = 10log(I1/1.0X10ˆ-12)
log-156/10 = I1/(1.0X10ˆ-12)
log-149/10 = I1/(1.0X10ˆ-12)
3.98 X 10ˆ5 = I1/(1.0X10ˆ-12)
7.94 X 10ˆ4 = I1 / (1.0 X 10ˆ-12)
I1 = 3.98 X 10ˆ-7
I1 = 7.94 X 10ˆ-8 W
Total Intensities, I = (3.98 X 10ˆ-7) + (7.94 X 10ˆ-8) = 4.77 X 10ˆ-7 SPL
= 10 log(I1/I0) = 10 log(4.77 X 10ˆ-7 / 1.0 X 10ˆ-12) = 56.79dB at Zone 5, Gallery during non-peak hour
Peak Hour Highest Reading: 61dB
Lowest Reading: 55dB
61 = 10log(I1/I0)
55 = 10log(I1/I0)
61 = 10log(I1/1.0X10ˆ-12)
55 = 10log(I1/1.0X10ˆ-12)
log-161/10 = I1/(1.0X10ˆ-12)
log-155/10 = I1/(1.0X10ˆ-12)
1.29 X 10ˆ6 = I1/(1.0X10ˆ-12)
3.16 X 10ˆ5 = I1 / (1.0 X 10ˆ-12)
I1 = 1.29 X 10ˆ-6
I1 = 3.16 X 10ˆ-7 W
Total Intensities, I = (1.29 X 10ˆ-6) + (3.16 X 10ˆ-7) = 1.61 X 10ˆ-6 SPL
= 10 log(I1/I0) = 10 log(1.61 X 10ˆ-6 / 1.0 X 10ˆ-12) = 62.07dB at Zone 5, Gallery during peak hour
Page | 92
4.3.11 Analysis for Data Collection SPL and Standard Equipment SPL Based on the calculated zoning SPL readings of equipment and calculated SPL readings for the data that is being collected from the decibel meter, the calculated SPL from the data collection are mostly similar to that of the calculated equipment SPL especially for areas with air conditioners and ceiling fans. However, for areas with speaker readings, calculated SPL is significantly lower (62.07dB for first floor gallery) when compared to the calculated equipment SPL or 83.01 dB for the first floor gallery. This probably implies that the speaker was not turned on to its maximum volume when it was being operated thus, indicated an overall lower reading.
Page | 93
4.3.12 Reverberation Time
Reverberation Time: Reverberation time is calculated to determine the amount of sound energy that is absorbed into the different types of construction materials in the structure as well as the interior elements such as building occupants and furniture that are housed within this closed space. Calculated Space: First Floor Gallery Space / Lounge Area Reverberation times are calculated based on different material absorption coefficient at 500Hz, 2000Hz and 4000Hz for peak and non-peak hours. -
Material Absorption Coefficient at 500Hz for non-peak hours.
-
Material Absorption Coefficient at 2000Hz for non-peak hours.
-
Material Absorption Coefficient at 4000Hz for non-peak hours.
-
Material Absorption Coefficient at 500Hz for peak hours.
-
Material Absorption Coefficient at 2000Hz for peak hours.
-
Material Absorption Coefficient at 4000Hz for peak hours.
Page | 94
Volume of First Floor Gallery Space / Lounge Area = ½ (3.2 + 6.16) (6.45) (10.7) + (6.76 x 1.54) (2.8) = 248.62m³ Material Absorption Coefficient at 500Hz, Non-Peak Hour with 2 persons contained within the space. Reverberation Time
Component
Material
Function
Ceiling
Plaster Finish Timber
Ceiling
Wall
Openings
Reinforce Concrete Glass Brick Fabric Glass Glass Glass Glass Glass
Floor
Furniture
Concrete Screed Timber Fabric Fabric Glass Fabric Fabric Fabric
Area (m²) [A] / Quantity 104.81
Absorption Coefficient [S] 0.1
Roof Truss Wall
12.49
0.14
65.34
0.06
Window Wall Blinds Pivot Door Sliding Door Sliding Door Sliding Door Sliding Door Floor
9.60 7.59 5.28 4.00
0.18 0.02 0.35 0.18
5.28
0.18
5.28
0.18
5.28
0.18
5.28
0.18
87.01
0.04
2.27 5.4 1.8 1
0.1 0.06 0.49 0.01
0.227 0.324 0.882
12.0 0.6 5 2
0.49 0.49 0.13 0.42
5.88 0.294 0.65
Bridge Carpet Sofa Side Table Sofa Sofa Paintings
People Non-Peak
Total Absorption [A] Reverberation Time
= (0.16 x V) / A = (0.16 x 248.62) / 36.99 = 1.08s
Sound Absorption [SA] 10.481 1.7486 3.9204 1.728 0.1518 1.848 0.72 0.9504 0.9504 0.9504 0.9504 3.4804
0.01
0.84 36.99
The reverberation time for the first floor gallery at 500Hz during non-peak hours is 1.08s. This falls within the comfort reverberation of between 0.8-1.3s. Hence, there is adequate acoustic absorption for a space such as this gallery. Page | 95
Material Absorption Coefficient at 2000Hz, Non-Peak Hour with 2 persons contained within the space. Reverberation Time
Component
Material
Function
Ceiling
Plaster Finish Timber
Ceiling
Wall
Openings
Reinforce d Concrete Glass Brick Fabric Glass Glass Glass Glass Glass
Floor
Furniture
Concrete Screed Timber Fabric Fabric Glass Fabric Fabric Fabric
Roof Truss Wall
Area (m2) [A] 104.81
Absorption Coefficient [S] 0.04
12.49
0.13
65.34
0.06
4.1924 1.6237 3.9204
Window Wall Blinds Pivot Door Sliding Door Sliding Door Sliding Door Sliding Door Floor Bridge Carpet Sofa Side Table Sofa Sofa Paintings
People Non-Peak
9.60 7.59 5.28 4.00
0.07 0.02 0.3 0.07
5.28
0.07
5.28
0.07
5.28
0.07
5.28
0.07
87.01
0.02
2.27 5.4 1.8 1
0.06 0.25 0.7 0.01
0.1362 1.35 1.26
12.0 0.6 5 2
0.7 0.7 0.13 0.5
8.4 0.42 0.65
Total Absorption [A] Reverberation Time
Sound Absorption [SA]
= (0.16 x V) / A = (0.16 x 248.62) / 27.87 = 1.42 s
0.672 0.1518 1.584 0.28 0.3696 0.3696 0.3696 0.3696 1.74
0.01
1 27.87
The reverberation time for the first floor gallery at 2000Hz during non-peak hours is 1.42s. This falls above the comfort reverberation of between 0.8-1.3s. Hence, this is deemed to be inappropriate since reverberations are to be kept minimal for a space that requires lower Page | 96 reverberation times.
Material Absorption Coefficient at 4000Hz, Non-Peak Hour with 2 persons contained within the space. Reverberation Time
Component
Material
Function
Ceiling
Plaster Finish Timber
Ceiling
Wall
Openings
Reinforce d Concrete Glass Brick Fabric Glass Glass Glass Glass Glass
Floor
Furniture
Concrete Screed Timber Fabric Fabric Glass Fabric Fabric Fabric
Roof Truss Wall
Area (m2) [A] 104.81
Absorption Coefficient [S] 0.02
12.49
0.1
65.34
0.1
2.0962 1.249 6.534
Window Wall Blinds Pivot Door Sliding Door Sliding Door Sliding Door Sliding Door Floor Bridge Carpet Sofa Side Table Sofa Sofa Paintings
People Non-Peak
9.60 7.59 5.28 4.00
0.04 0.03 0.35 0.07
5.28
0.04
5.28
0.04
5.28
0.04
5.28
0.04
87.01
0.03
2.27 5.4 1.8 1
0.07 0.45 0.55 0.01
0.1589 2.43 0.99
12.0 0.6 5 2
0.55 0.55 0.35 0.5
6.6 0.33 1.75
Total Absorption [A] Reverberation Time
Sound Absorption [SA]
= (0.16 x V) / A = (0.16 x 248.62) / 29.34 = 1.35s
0.384 0.2277 1.848 0.28 0.2112 0.2112 0.2112 0.2112 2.6103
0.01
1 29.34
The reverberation time for the first floor gallery at 4000Hz during non-peak hours is 1.35s. This falls above the comfort reverberation of between 0.8-1.3s. This similarly indicates how there is inadequate acoustic absorption within the space during non-peak hours. Page | 97
Material Absorption Coefficient at 500Hz, Peak Hour with 30 people contained within the space. Reverberation Time
Component
Material
Function
Ceiling
Plaster Finish Timber
Ceiling
Wall
Openings
Reinforce d Concrete Glass Brick Fabric Glass Glass Glass Glass Glass
Floor
Furniture
Concrete Screed Timber Fabric Fabric Glass Fabric Fabric Fabric
People Non-Peak
Roof Truss Wall
Area (m2) [A] / Quantity 104.81
Absorption Coefficient [S] 0.1
12.49
0.14
65.34
0.06
10.481 1.7486 3.9204
Window Wall Blinds Pivot Door Sliding Door Sliding Door Sliding Door Sliding Door Floor Bridge Carpet Sofa Side Table Sofa Sofa Paintings
9.60 7.59 5.28 4.00
0.18 0.02 0.35 0.18
5.28
0.18
5.28
0.18
5.28
0.18
5.28
0.18
87.01
0.04
2.27 5.4 1.8 1
0.1 0.06 0.49 0.01
0.227 0.324 0.882
12.0 0.6 5 30
0.49 0.49 0.13 0.42
5.88 0.294 0.65
Total Absorption [A] Reverberation Time
Sound Absorption [SA]
= (0.16 x V) / A = (0.16 x 248.62) / 48.75 = 0.82s
1.728 0.1518 1.848 0.72 0.9504 0.9504 0.9504 0.9504 3.4804
0.01
12.6 48.75
The reverberation time for the first floor gallery at 4000Hz during peak hours is 0.82s. This falls within the comfort reverberation of between 0.8-1.3s. Hence, this is appropriate for a space such as this gallery. Page | 98
Material Absorption Coefficient at 2000Hz, Peak Hour with 30 people contained within the space. Reverberation Time
Componen t
Material
Function
Area (m2) [A]
Absorption Coefficient [S]
Ceiling
Plaster Finish Timber
Ceiling
104.81
0.04
Roof Truss Wall
12.49
0.13
65.34
0.06
Window Wall Blinds Pivot Door Sliding Door Sliding Door Sliding Door Sliding Door Floor
9.60 7.59 5.28 4.00
0.07 0.02 0.3 0.07
5.28
0.07
5.28
0.07
5.28
0.07
5.28
0.07
87.01
0.02
2.27 5.4 1.8 1
0.06 0.25 0.7 0.01
0.1362 1.35 1.26
12.0 0.6 5 30
0.7 0.7 0.13 0.5
8.4 0.42 0.65
Wall
Openings
Reinforced Concrete Glass Brick Fabric Glass Glass Glass Glass Glass
Floor
Furniture
Concrete Screed Timber Fabric Fabric Glass Fabric Fabric Fabric
Bridge Carpet Sofa Side Table Sofa Sofa Paintings
People Non-Peak
Total Absorption [A] Reverberation Time
= (0.16 x V) / A = (0.16 x 248.62) / 41.87 = 0.95s
Sound Absorption [SA] 4.1924 1.6237 3.9204 0.672 0.1518 1.584 0.28 0.3696 0.3696 0.3696 0.3696 1.74
0.01
15 41.87
The reverberation time for the first floor gallery at 4000Hz during peak hours is 0.95s. This falls within the comfort reverberation of between 0.8-1.3s. Hence, this is appropriate for a space such as this gallery. Page | 99
Material Absorption Coefficient at 4000Hz, Peak Hour with 30 people contained within the space. Reverberation Time
Componen t
Material
Function
Area (m2) [A]
Absorption Coefficient [S]
Ceiling
Plaster Finish Timber
Ceiling
104.81
0.02
Roof Truss Wall
12.49
0.1
65.34
0.1
Window Wall Blinds Pivot Door Sliding Door Sliding Door Sliding Door Sliding Door Floor
9.60 7.59 5.28 4.00
0.04 0.03 0.35 0.07
5.28
0.04
5.28
0.04
5.28
0.04
Wall
Openings
Reinforced Concrete Glass Brick Fabric Glass Glass Glass Glass Glass
Floor
Furniture
Concrete Screed Timber Fabric Fabric Glass Fabric Fabric Fabric
Bridge Carpet Sofa Side Table Sofa Sofa Paintings
People Non-Peak
5.28 0.03
2.27 5.4 1.8 1
0.07 0.45 0.55 0.01
Total Absorption [A] Reverberation Time
= (0.16 x V) / A = (0.16 x 248.62) / 43.34 = 0.92s
2.0962 1.249 6.534 0.384 0.2277 1.848 0.28 0.2112 0.2112 0.2112 0.2112
87.01
12.0 0.6 5 30
Sound Absorption [SA]
0.35 0.5
2.6103 0.1589 2.43 0.99 0.01 6.6 0.33 1.75 15 43.34
The reverberation time for the first floor gallery at 4000Hz during peak hours is 0.92s. This falls within the comfort reverberation of between 0.8-1.3s. Hence, this is appropriate for a space such as this gallery. Page | 100
Reverberation Time Analysis and Conclusion By obtaining the reverberation timings for the main first floor gallery for 500Hz, 2000Hz and 4000Hz, we are able to understand the acoustic reverberation patterns for sounds of different frequencies. During non-peak hours, reverberation timings indicate timings of 1.08s, 1.42s and 1.38s for sounds of 500Hz, 2000Hz and 4000Hz respectively. However, during peak hours reverberation timings hover around the 0.8s to 0.95s region which is within the range of comfort reverberation between 0.8 – 1.3s. This thus suggests that the influx of visitors or occupants into the area during peak hours help in enhanced sound absorption
Figure 40: Section showing reverberation of acoustic rays
Most of the higher reverberation timings during non-peak hours are also attributed to the double volume space that is present within the first floor gallery. The bouncing of acoustic rays onto the gallery’s glass façade as well as the sloping roofline indicates how sound bounces of these materials and onto the gallery space. When sound from the speakers’ tweeters bounce off glass which bears a lower acoustic absorption rating, sound gets reflected more than it gets absorbed thus, translating to a higher reverberation timing.
Page | 101
4.3.13 Sound Reduction Index
Figure 41: Gallery space of CORE Design Gallery
Identifying the first floor gallery as a main space to analyze the acoustic transmission into and from the area, this space incorporates not only the gallery space but the immediate corridor that leads to the office area. Establishing the office area as the secondary area to record sound transmission into that particular space, understanding whether acoustic measures such as the selection of materials are adequate to create a sound buffer between these spaces is essential to identify the acoustic ratings of these two spaces.
Page | 102
For Gallery and Corridor Area,
Materials
Concrete Wall Brick Wall Glass Doors Glass Wall Total Surface Area TAV
Gallery and Corridor Area Surface Area / m2 Transmission Coefficient of Material 75.48 6.31 x 10-5 7.59 5.01 x 10-6 10.96 2.51 x 10-4 9.60 2.51 x 10-4 103.63
SN x TCN 4.76 x 10-3 3.80 x 10-5 2.75 x 10-3 2.41 x 10-3
= (4.76 x 10-3 + 3.80 x 10-5 + 2.75 x 10-3 + 2.41 x 10-3) / Total Surface Area = 9.61 x 10-5
SRIOverall
= 10log10 (1/9.61 x 10-5)
SRIOverall
= 40.17 dB Page | 103
For Office/ Meeting Room,
Materials
Concrete Wall Brick Wall Glass Doors Glass Wall Total Surface Area TAV
Office/ Meeting Room Surface Area / m2 Transmission Coefficient of Material 27.60 6.31 x 10-5 11.70 5.01 x 10-6 4.00 2.51 x 10-4 7.20 2.51 x 10-4 50.5
SN x TCN 1.74 x 10-3 5.86 x 10-5 1.00 x 10-3 1.81 x 10-3
= (1.74 x 10-3 + 5.86 x 10-5 + 1.00 x 10-3 + 1.81 x 10-3) / Total Surface Area = 9.13 x 10-5
SRIOverall
= 10log10 (1/9.13 x 10-5)
SRIOverall
= 40.40 dB
Page | 104
4.3.14 Sound Reduction Index Analysis and Conclusion
Based on the calculated values of 40.17 dB and 40.40 dB respectively for First Floor Gallery Area and Corridor Area and for the First Floor Office Area, this implies that the acoustic buffer between each area as well as the sound buffer from outdoor noise is adequate enough to isolate each space from external as well as adjacent noise sources. Both areas incorporate the use of a variety of materials such as bricks, concrete and glass. The balance of the use of effective materials that help provide better acoustic absorption with materials of poor acoustic ratings help in the overall reduction in sound transmission between spaces. Also, the corridor that leads the gallery into the office area acts as a buffer space where noise levels will be reduced before entering the office area. Likewise happens when sound transmits through the corridor area before entering the first floor gallery. Voids within the gallery area also enable noise to be transmitted to the ground floor and not be wholly contained on the first floor.
Page | 105
5.0 Evaluation and Conclusion 5.1
Lighting
5.1.1
Improvements for Lighting Based on the lighting observations and analysis, most of the main spaces are
inadequately lit which suggests the types of luminaires which may be deemed to be poorly employed. Pendant lighting for general space illumination also proves to be insufficient given that light is not be dispersed uniformly across the room. As such, the use of recessed lighting that may be distributed evenly through a grid system to help illuminate every corner of the room would thus reflect adequate illumination ratings.
5.1.2
Limitations with Lighting Whilst the introduction of uniformly distributed recessed lighting may solve the poor
distributed lighting issue within the space, the selection of luminaires are also crucial to provide sufficient lighting for increased productivity. The use of dimmers may also be introduced to help achieve desired light levels within these spaces. While employing these measures, considerations have to be consistently taken to ensure that these lights do not deteriorate the quality of artwork over time.
5.2
Acoustics
5.2.1
Improvements for Acoustics Most of the acoustic issues that are generated are due to the large volume space
that exists within the first floor gallery area. Non-peak hours saw higher reverberation timings when compared to that during peak hours which saw an increase the number of visitors which act as acoustical buffers or absorbers so as to reduce the reverberation time for this space. As such, by introducing more furniture within the space or an acoustic wall panel to absorb noise within the space would help to increase noise absorption.
Page | 106
5.2.2
Limitations with Acoustics Introduction of furniture might serve to absorb the noise but due to the sheer volume
of space created by the high ceilings; this might not improve the conditions drastically. A better alternative would be to lower the ceiling by introducing a gypsum suspended ceiling. The downside to this would be the loss in the overall ambience of the space from the high ceiling levels.
5.3
Conclusion Overall, the gallery has some hits and misses with lighting seeing much room for
improvement. However, these are empirical evaluations without taking the poetic side of the design into account. After discussing with the owners of the space, some elements of lighting and acoustics were sacrificed in order to achieve a calm and peaceful ambience and to bring out a certain character of the space.
Page | 107
References STC Chart (n.d.). STC Ratings for Brick and Concrete Block. Retrieved from http://www.sae.edu/reference_material/pages/STC%20Chart.htm on 15 October 2014 Paroc Group (2014). Sound Insulation. Retrieved from http://www.paroc.com/knowhow/sound/sound-insulation on 10
October 2014
ThomasNet (2014). Sound Absorption Coefficients. Retrieved from http://www.acousticalsurfaces.com/acoustic_IOI/101_13.htm on 13 October 2014 Absorption Coefficients of common building materials and finishes. (2014). Retrieved from http://www.sae.edu/reference_material/pages/Coefficient%20Chart.htm on 7 October 2014 Hongkong Institute of Architects. (2008). Wave Motion, Noise Control in
Architecture.
Harris, Cyril M. Noise Control in Buildings: A Practical Guide for Architects and Engineers. New York: McGraw-Hill, 1993. Neufert, Ernst and Peter. Neufert Architects’ Data. Oxford: Wiley-Blackwell,
2012
AZO Network (2014) . Sound Transmission and Insulation in Brick and Masonry Walls. Retrieved from http://www.azom.com/article.aspx?ArticleID=1326 on 5 October 2014 Robert B. (n.d.) Noise Control for Buildings. Guidelines for Acoustical Problem Solving. Retrieved from http://www.certainteed.com/resources/NoiseControl%20Brochure%203 029-121.pdf on 5 October 2014 Long, M. (2006).Architectural acoustics. Amsterdam: Elsevier/Academic Press. Barton, C. K., & Construction Engineering Research Laboratory. (1987). Development of LITE--a graphic module for lighting analysis in the Computer-Aided Engineering and Architectural Design System (CAEADS). Champaign, IL: US Army Corps of Engineers, Construction Engineering Research Laboratory. Calculux Indoor - Philips Lighting Singapore. (n.d.). Retrieved from http://www.lighting.philips.com/pwc_li/cn_zh/connect/tools_literature/Assets/downloads/manual_i ndoor.pdf CIBSE. (2002). Code for Lighting. Burlington: Elsevier. Coefficient Chart. (n.d.). Retrieved from http://www.sae.edu/reference_material/pages/Coefficient%20Chart.htm Core Design Gallery - Art Gallery and Design Workshop. (n.d.). Retrieved from http://www.coredesigngallery.com/ Deru, M., Torcellini, P., Sheffer, M., & Lau, A. (2005). Analysis of the Design and Energy Performance of the Pennsylvania Department of Environmental Protection Cambria Office Building. doi:10.2172/15016075
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INTERIOR LIGHTING DESIGN A STUDENT'S GUIDE. (n.d.). Retrieved from http://www.slideshare.net/nosuhaila/interior-lighting-design-a-students-guide Malaysia. (2007). Code of practice on energy efficiency and use of renewable energy for nonresidential buildings (first revision). Putrajaya: Department of Standard Malaysia. subtle variations: the uses of artificial and natural light in the menil collection, houston, texas. (n.d.). Retrieved from http://www.arch.ced.berkeley.edu/vitalsigns/bld/toolkit_studies/menil%20collection%20-%20Subtle%20Variations.pdf Technical - Photometric Data Guide. (n.d.). Retrieved from http://lightsbylinea.com/index.php?route=information%2Finformation&information_id=10
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Appendix List of Figures Figure 1: View from Entrance of CORE Design Gallery 7 Figure 2: Ground Floor Plan (not to scale) 9 Figure 3: First Floor Plan (not to scale) 9 Figure 4: Roof Plan (not to scale) 10 Figure 5: Section of Building (not to scale) 10 Figure 6: Plan showing data collection points 11 Figure 7: 01dB digital sound meter 11 Figure 8: Lutron digital lux meter LX-101 11 Figure 9: Reading Interval for Lighting Figure 10: Reading Interval for Acoustics 12 Figure 11: First Floor Plan of Cambria Office Building 17 Figure 12: Second Floor Plan of Cambria Office Building 17 Figure 13: Daylighting design features of the Cambria Building 18 Figure 14: Outdoor Illuminance for July 13-16, 2001: 21 Figure 15: Illuminance measurements at workstations for the first floor; southwest office area from July 13-16, 2001 (task lights used in cuble 10 ft from outside wall) 23 Figure 16: Southwest and Northwest office area 23 Figure 17: Illuminance measurements at workstations for the second floor; southwest office area from July 13-16, 2001 (no task lighting) 25 Figure 18: Daylighting measurements at workstations for the second floor; northwest office area on July 13-16, 2001 (task lights used in cubicles 18 ft from outside wall) 25 Figure 19: Northwest Office area near mid-day 26 Figure 20: Lighting Analysis Diagram of Menil Collection 28 Figure 21: Placement of Lighting for Menil Collection 28 Figure 22: Zoning of First Floor of CORE Design Gallery 30 Figure 23: Section X 31 Figure 24: Section Y 31 Figure 25: Section Z 32 Figure 26: Light Analysis Diagram for Daylight 37 Figure 27: Light Analysis Diagram for Artificial Lighting 53 Figure 28 : Reverberation Time Graph 57 Figure 29: The YTU auditorium (before renovation) 60 Figure 30: The YTU auditorium (after renovation) 60 Figure 31: Section of the YTU auditorium (after renovation) 65 Figure 32: Plan of YTU auditorium (after renovation) 65 Figure 33: STI in YTU auditorium 66 Figure 34: Location of Site in relation to Main Road 69 Figure 35: Placement of Air Circulators 72 Figure 36: Nodes of Human Activity 73 Figure 37: Placement of Speakers 74 Figure 38: Acoustic Ray Diagram (from Speakers) 75 Figure 39: Zoning of CORE Design Gallery (for Acoustic analysis) 79 Figure 40: Section showing reverbatation of acourstic rays 101 Figure 41: Gallery space of CORE Design Gallery 102 Page | 110
List of Tables Table 1: Daylight factors and distribution (Department of standards Malaysia, 2007) 14 Table 2: Percentage of artificial and natural light: 29 Table 3: Light Data during Peak 33 Table 4: Light Data during Non-Peak 33 Table 5 : Acoustical Parameters and Recommended Ranges 59 Table 6: Surface materials in auditorium, their surface area and absorption coefficient (based on Harris, 1994: Cavanaugh & Wilco, 1999) 62 Table 7: RTs of auditorium, before renovation (measured) and after renovation (calculated) 62 Table 8: Measured and acceptable BSLs (air conditioning) 63 Table 9: Measured, calculated and optimum RTs of YTU auditorium for speech activities 63 Table 10: Measured and optimum EDTs of the YTU auditorium 64 Table 11: D50 values of YTU auditorium 64 Table 12: Measured STI values for unfurnished and furnished (before and after renovation) conditions of the YTU auditorium 66 Table 13: Room average measurement results and optimum values for acoustic parameters of the YTU auditorium. (*500-1000 Hz average) 67 Table 14: Noise Level Data for Peak 70 Table 15: Noise Level Data for Non-Peak 70 Table 16: Sound Environments with their corresponding Sound Pressure Levels 88
Page | 111