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Nanyang Technology University( School of Art, Design and Media, Singapore )

Project 1 : Case Study: Identifying Innovative Passive Design Strategies

Building science ( ARC 2413)Tutor : Mr. Prince

Chu Szi Wei 0314160 Christiody 0304191 Poh Ziyang 0807P68823 Sean Hiu Ji Ren 0309874 Soe Woei hao 0309924 Usman Farooqi 1102p11235 William Yap 0314127

Introduction (Singapore)

Singapore is an island which located at the end of Malayan Peninsula between Indonesia and Malaysia. Singapore is one of the South East Asia’s modern city for over a century. The island nation of Singapore lies one degree north of Equator in Southern Asia. On the other hand, Singapore blends Chinese, Malay, Indian, and English Cultures and also religions together. Besides that, Singapore also has excellent infrastructure to let the visitor enjoy the sites and attraction in a secure, clean and green environment. (Figure 1)

Figure 1. Map of Singapore (Location)

Figure 2. Singapore Climate Graph

The location of Singapore is on the north of the Equator, it makes Singapore has a tropical climate or called as a tropical country. Singapore is Hot and Humidity.During daytime the temperatures average around 31°C, but in December and January it’s slightly cooler, April and May is the hottest month. Night time the temperature rarely drop below 23°C. The lowest temperature ever recorded in Singapore is 19°C.

There are no distinct wet or dry seasons. The region is affected by two different monsoons. December to March is generally the Northeast monsoon and more frequent rain particularly from November to January. Besides that, May to September is the dryer climate for the southwest monsoons. Then, the beginning and the end of the two monsoons season are not well defined.

The region are extremely humid, with humidity level between 70% - 85%. On rainy day unreasonable to expect the humidity to reach 100%. March and September are particularly humid and often very uncomfortable. On the other hand, Thunder storms are also a very regular phenomenon in Singapore. (Figure 2)

1.0 B Project Description

Nanyang Technological University (NTU) of Singapore with its School of Art, Design & Media building represents one of the finest, if not best, sustainable building ever built. With its swirling facade and smart usage of the natural surrounding context, this building provides an interesting twist into sustainable designs with its creativity and boldness. Designed by the CPG consultants, this five storey campus shows that not all sustainable building has to be dull and shapeless. In fact, NTU-ADM was given the Green Mark Platinum award, one of the high a building can obtain, by the Building and Construction Association (BCA). Green Mark Award is the benchmark for design, construction and operation of high performance green building. The award is separated into a few categories which are Certified, Gold, Goldplus and Platinum (BCA Green Mark Award Rating) of course with the later being the best. The award is given based on how much points are collected as each category is satisfied based on a certain criteria.

Green Mark for EXISTING Buildings – Point Allocation

Part 1 – Energy Efficiency Pts

1-1 Energy Efficiency 22

1-2 Systems Energy Efficiency 23

1-3 Energy Monitoring 4

1-4 Energy Policy & management 4

1-5 Renewable Energy/Energy Efficient Features 10

Sub-total for Part 1 (Max 50 pts) 63

Part 2 – Water Efficiency Pts

2-1 Water Monitoring 2

2-2 Water Efficient Fittings 12

2-3 Alternative Water Sources 2

2-4 Water Efficiency Improvement Plans 1

Part 2 – Water Efficiency Pts

2-5 Cooling Towers 1

Sub-total for Part 2 18

Part 3 – Sustainable Operation & Mgt Pts

3-1 Building operation & maintenance 4

3-2 Post occupancy evaluation 2

3-3 Waste management 8

3-4 Greenery 3

3-5 Public Transport Accessibility 2


Part 4 – Indoor Environmental Quality Pts

3-1 Indoor air quality performance 6

3-2 Environmental protection 5

3-3 Lighting quality 4

3-4 Thermal comfort 2

3-5 Internal noise level 1


GREEN MARK AWARD RATING

Green Mark Try Again Certified Gold Gold Plus Platinum

Score 0 49 50 74 75 84 85 89 90 100

Green Mark Rating Green Mark Points

Platinum 90 & above

Goldplus 85 to <90

Gold 75 to <85

Certified 50 to <75

Figure 1.0 B Glass Wall feature to allow light to penetrate into the building to reduce cost of interior lighting

To reinforce the statement on how much NTU-ADM has achieved in sustainability, one of the major achievement were its savings which can total up to 120,000 kWh per year and more than 1,170 cubic meters of water saved for annum. This allows it to have a lower operation and maintenance costs.

Design Concept

What makes this building interesting is how it distinct itself with the other surrounding buildings but still maintain to blur the lines between man-made and natural feature. This key feature of the building allows this transparency and connectivity of both interior and exterior environment. Even the interior portrays great sense of continuity of various spaces from one to another. It does not feel as if the building seems to be disconnected from one wing to another. Internal glass walls further enhance this connection with its smooth flow allowing one to have visual of the surrounding which promotes interaction with context. Additionally, this creative sort of design allows spaces to be formed more freely. It clearly tries to invent spaces that develop a relationship between teachers and student despite having different kind of spaces like auditorium and studio spaces.

This is further developed with the integration of its curvy hill-like design and applying green roof feature on it. Not only does the green roof provide many benefits but it also creates additional spaces for the users to experience as they go along their daily routine within the campus.

Figure 1.1 B Green Roof feature to reduce heat gain and allows the building to blend with the surroundings

Figure 1.3 B Roof Plan of NTU - ADM

Figure 1.3 B Floor Plan of NTU - ADM

Figure 1.4 B A Section of a Floor Plan of NTU – ADM (Library)

Figure 1.5 B Section of NTU - ADM

2.0 Climate Data

Singapore is 1 degree north of the equator as shown in Figure 2.1. Singapore's climate is classified as tropical rainforest climate, with no true distinct seasons. Owing to its geographical location and maritime exposure, its climate is characterized by uniform temperature and pressure, high humidity and abundant rainfall. So it is almost always warm and wet.

Figure 2.1 Singapore’s Location in the world Map

Figure 2.2 Average Rainy Days in Singapore

Figure 2.3 Average precipitations in Singapore

According to Figure 2.2 and Figure 2.3, the average annual rainfall is around 2,340 mm in total. The highest being at the month of December on average about 310mm and the lowest being on average 150mm on three different months which is April, June, and August. Additionally, the highest 24-hour rainfall figures ever recorded in history was 512 mm (1978), 467 mm (1969) and 366 mm (19 December 2006).

From Figure 2.4, The average temperature of Singapore hovers around the range of a minimum of 23°C and a maximum of 31°C with February until June being the hottest months on average. This is mainly due to light winds and strong sunshine during those months. Additionally, the highest recorded temperature is 36.0°C on 26 March 1998 and the lowest recorded temperature was 19.7 °C in January 1934. Temperature sometimes goes above 33.2 °C and can reach 35 °C at times.

As seen from Figure 2.5, an average humidity in Singapore is around 75% to 80% throughout the year. However, during prolonged heavy rain, relative humidity can often reach to about

Figure 2.4 Average Temperature of Singapore

Figure 2.5 Average Humidity in Singapore

100%. This usually happens towards the western side of Singapore. Generally, there is much more rainfall on the western side of the island than on the eastern portion of Singapore, owing to a rain shadow effect.

Thus, the eastern side of Singapore is much drier and slightly hotter than western Singapore. This can cause slight weather disparities from one side of the island to the other. This is significant to note because even a small hill such as Bukit Timah can cause this phenomenon. Despite Singapore's small size, there may be sunshine on one side while there is rain on the other.

Further contrasts that prevent true all-year uniformity are the monsoon seasons which happen twice each year. The first one is the Northeast Monsoon which occurs from December to early March. The second is the Southwest Monsoon season which occurs from June to September. Periods between monsoon seasons receive less rain and wind. During the Northeast Monsoon, northeast winds prevail, sometimes reaching 20 km/h. There are cloudy conditions in December and January with frequent afternoon showers.

Spells of widespread moderate to heavy rain occur lasting from one to three days at a stretch. It is relatively dry in February till early March although rainfall still exceeds 120mm. It is also generally windy with wind speeds sometimes reaching 30 to 50 km/h in the months of January and February. During the Southwest Monsoon season, southeast winds prevail. Isolated to

Figure 2.6 Percentage of rainfall distribution in Singapore

scattered showers occur in the late morning and early afternoon. Early morning "Sumatra" squall lines are common.

For our building that we chose, NTU Art & Design faculty, the climate of Singapore influenced the building in many ways and we believe the architect also took into consideration of the location of the building during the design phase and also made changes to fit the climatic response of the site.

NTU Art & Design faculty has an interesting shape that integrates the landscape into its roof which allows it to gain many benefits like lowering the temperature of the surrounding context. Due to the material used by the building which mainly consist of thick laminated glass and also bare concrete as the walls, this passive design puts this building in an advantages position. Additionally, to certify its position, a water feature is added in the centre of the building to provide a cooling effect. With the high temperature and humidity of Singapore, this building is able to handle the problems that usually occur like an increase of temperature of the building envelope during the day and the lack of natural lighting causing the building to consume much energy to function

Figure 2.7 Roof Plan of NTU Art & Design faculty

3.0 Wind Analysis

Figure 3.0 Wind rose at Singapore

The wind rose indicates the wind frequency by hours for the whole year from different

directions. Besides, it shows the wind speed distribution from less than 10km/h up to 50km/h in

the circular graph. The lighter the colour the more hours the wind is coming from that

particular direction and particular speed. We can learn from the diagram that the wind is

coming from mainly from north east direction, though the wind from all other direction is quite

frequent. The frequency of wind speed is higher in the range of 10km/h to 30km/h. Wind speed

higher than 30km/h is rarer.

The Art & Design Faculty of Nanyang Technology University is surrounded by trees and

buildings of similar height, hence the wind does not affect much of the building design. It is not

a tall building and all facades are all curved and streamlined. This helps to reduce lateral wind

pressure though the wind force is not strong in that area. The central courtyard may

inducepositive or negative wind pressure at times depending on wind direction and intensity, as

it is surrounded by three sides, but this should not create problems as the wind pressure is mild

most of the time. In fact, this creates breeze to bring away the moisture from the water feature

and provide perceptible air movement to enhance thermal comfort.

As the whole building is air tight and fully mechanically ventilated, natural ventilation does not

play an important role inside the building.

Figure 3.1 Wind flow diagram

4.0 Sun Analysis

Singapore is located just 1°17’ north from the equator, the sun at noon is always above the

head and tilts slighted towards north in months close to June and tilts towards south in months

close to December. The morning and evening sun is always on the east and west respectively

and just slightly tilted towards south or north depending on months.

The long axis of the Art & Design Faculty is running east-west and the short axis is running

north-south. This configuration is good in Singapore as the low morning and evening sun is

always hitting the building envelop at façade facing east and west, and hence heating up the

east and west façades. At noon, the sun is always almost above the building and heating up the

roof.

Figure 4.0 Annual sun path at Art & Design Faculty,NTU. The sun is at 5pm on 22nd June.

Figure 4.1 5pm at 21st June Solstice.

In June solstice day, the sun is at north side of the building. In the afternoon the sun would

warms up the north façade at the same time causing glare in the building. Art & Design Faculty

building handles this by using double glazing with low-emission coating on inner glaze and

tinted glaze on the outer layer. This enables natural daylight to penetrate into the building

without much heat.

Figure 4.2 5pm at 21st December Solstice.

In December solstice day, the sun is at south of the building. As oppose to June’s sun path the

sun warms up the south façade in the afternoon at the same time causing glare in the same

area. Since the whole building is double glazed, heat and glare is reduced in the building.

Shading devices could be added to the building to reduce direct contact of sunlight on the

building envelop to reduce heat and glare. However, this might compromise on the clean line

design and architect’s vision.

Surface insolation should be showing similar result as Kuala Lumpur’s building. The roof should

receive about 10 times more solar insolation compare to the facades. Hence, to reduce heat

effectively for the indoor environment, Art & Design Faculty building has a green roof. The

green roof has high thermal resistance (R-value) and thus low U-value. It can effectively keep

the heat out and reduce the cooling load. Moreover, the double glazed façade throughout the

building can reduce the heat to penetrate into the building.

Natural day light can be harvested in the building without much glare thanks to the tinted glass.

The building does not has deep plan, and thus sunlight can be used to light up almost all area in

the building during day time.

Figure 4.3 Shadow range on the day 21st December.

The courtyard in the centre may be too hot to be occupied during day time as there is no

shading device. The shadow of the building itself is not sufficient to provide enough shade in

the central courtyard. The concrete floor and the glass walls around the courtyard may reflect

heat and contain the heat in the courtyard. However heat can be stored in the pool and

concrete as they have high thermal mass, hence the surface temperature rises slowly during

day time and purge away during night time.

5.0 Passive Design FeatureGreen Roof

Without question, one of the dominant factor that makes the Nanyang Technology University (Art & Design), NTU, a green and sustainable building is the roof itself which are covered with grass. This green roof system is not new in the context of being sustainable or having a sustainable design but this particular NTU faculty steps it up by allowing the green roof design to be applied throughout its creative building form.

What makes this green roof design unique is the seem-less blend of both structure and the surrounding context. This is further amplified by the structures organic shape which forms a hill-like structure and it really works at the end of the day. The construction of the green building can produce many beneficial outcomes. One of it would be for to cool off the building as the vegetation of the roof acts as an insulator of heat. Due to the location of the country, Singapore, the weather is always hot and humid throughout the year, hence, climate and wind considerations are usually constant with a few exceptions of some variation between months. The construction of a green roof building could also potentially lower energy usage as the insulation of the heat reduces the heat gain within the building. Reason why a green roof is able to do so is because of the absorption of sunlight by the plants through photosynthesis. Hence, a lower heat gain is produced throughout the year which leads to a lower cost in adjusting thermal comfort of the building. Additionally, this effect is amplified further due to the extensive usage of the green roof throughout NTU.

Figgure 5.1 NTU Green Roof

Benefits of Green Roof

Reduced energy use by absorbing heat and act as insulators for buildings, reducing energy needed to provide cooling and heating.

Reduced air pollution and greenhouse gas emissions by lowering air conditioning demand, green roofs can decrease the production of associated air pollution and greenhouse gas emissions. Vegetation can also remove air pollutants and greenhouse gas emissions through dry deposition.

Improved human health and comfort, by reducing heat transfer through the building roof, can improve indoor comfort and lower heat stress associated with heat waves.

Enhanced stormwater management and water quality can reduce and slow stormwater runoff in the urban environment; they also filter pollutants from rainfall.

Improved quality of life can provide aesthetic value and habitat for many species.

A green roof usually consists of five layers which starts with the vegetation layer and follow up by the soil in which the vegetation grows. The following layers are followed up by protective sheets such as a filtration sheet, drainage layer, protection layer and finally a waterproofing layer before the super structure of the building to prevent any dirt or water to sip into the walls and ceiling of the building.

The grass used on the green roof is called manilagrass and with very good reasons too as it is easily maintained and does not require much upkeep. Known also as ZoysiaMantrella or in Malaysia, rumputsiglap, this plant has many variance, with different sizes of leaf blade depending on the continent it is located at.

Figure 5.2 Layers of the Green

5.0 Passive Design Feature

Double Glazed GlassBesides the Green Roof, another dominant factor would be the windows constructed on the walls

around the NTU building. The glass is actually a special glass called double glazed glass which is

constructed using two planes of glazed glass with a gap between each plane for about 6 – 12mm and is

filled with usually air or an insulating gas like argon. The reason behind it would be using an insulating

gas like argon will decrease conductance of air space between the layer of glass. What this means is that

with the usage of a slow and insulating gas, the heat transfer between the inside and outside are very

much reduced. For further explanation, the reason behind this phenomenon is because the density of

the air between the 2 glass panelsare higher than that of the density of air outside.

Figure 5.0 NTU During the day

Figure 5.1 NTU During the night

A double glazed glass consists of 2 components of which are the spacer and the glass panel. A spacer is

the piece that separates the two panes of glass in an insulating glass system, and seals the gas space

between them. Spacers were made primarily of metal and fiber, which manufacturers thought provided

more durability, newer spacers are also made of foam to provide the window with sound dampening

properties while making the window into a thermal barrier such that heat flow through the bracer is

reduced. Having being cut down to its appropriate dimension both the spacers and glass panels are

cleaned before going through the assembly line. An adhesive sealant called polyisobutylene is applied to

the face of the spacer on each side and the glass panels are pressed against the spacer. Innerd gas is

then pumped into 2 holes which are drilled into the spacer, afterwards the units are then sealed on the

edge side using eitherpolysulfide or silicone sealant or similar material to prevent humid outside air

from entering the unit.

Figure 5.2 Anatomy of double Glazed Glass

Figure 5.3 Panoramic view of the centre courtyard

The glasses used in the NTU are no different from the normal average glass used in normal housing

schemes. As Picture A shows, the double glazed windows are used extensively throughout the facade

and wall of NTU’s Art & Design faculty to reduce the energy consumption within the building itself. With

the double glazed windows, the heat from the sunlight does not penetrate into the building completely

however there is a 100% light penetration into the building. The heat also does not transfer fully from

the inside of the building to the outside which prevents the inside of the building from becoming too

cold.

This not only reduces cost to increase the thermal comfort within the building due to lack of heat lost

but also retains enough heat within the building to keep the building in a comfortable environment.

Besides saving energy and cost in reaching thermal comfort, the usage of double glazed windows as

mentioned increases the light intensity in the building, hence saving cost in electricity to lighten up the

interior. Additionally, the absence of the usage of windows allows this building to be easily constructed

without much hassle when putting up the wall of the building.

6.0 Conclusion

Nanyang Technological University – Art, Design and Media

NTU school of Art, Design and Media is a complete representation of a green design and, it portrays an astute example for future architects who are willing to learn more about a green building. The applications of a passive design are kept in mind through out the building, pointing out the green roof and use of double glazed glass. The green roof, which lays upon the entire roof of the structure, ensures a minimal transfer of heat through the roof and then the ceiling. A green roof can minimize up to 70% of heat transfer during day time which allows the interior to be as comfortable as possible.

The several layers of a green roof allow the heat transfer to reduce at phenomenal levels, providing a lower cost of air-conditioning the interior.

Figure 6.0 layers which makes up the green roof

Besides the green roof, the entire department is walled with double glazed glass. This maximizes the use of natural light during the day and provides the necessity heat transfer to maintain an affluent environment within the structure. Use of glass on the entire structure keeps the interior lit at day timesand, is an assurance of minimum usage of electricity. These features play a vital role in keeping a green environment within the structure. Though, the use of green features are of main focus in this design but, the courtyard itself lacks a thought process to its emergence. The courtyard is an oval bowl or contains a valley like depth to it. This particular design allows minimal air flow through the space, as its covered from all sides. An analysis and a keen study reveals the imperfections in environmental considerations for the courtyard. In hand with a minimal air flow, the courtyard is open to direct sunlight at noon and reflected heat from the glass walls. All these factors add up to bring a very congested space. The ponds within the courtyard hold a purpose of precipitation and control of excessive heat in the day, but, they actually add up to the humidity of the space. A cunning improvisation to the design is required to manage this issue. The suggested solution would be an addition of water flow at the roof edges so that precipitation at a height causes cooler winds to enter the courtyard which in-turn would cool down the space within the courtyard. Overall the balanced blend of green roof and the use of glass makes this building green in every way possible. To sum-up, this design allows a maximum use of daylight and minimum transfer of sun heat. This balance results in a complete green approach to a design.