INDEX 1.0 Building Profile 1.1 Description 1.2 Highlights of Passive Design 2.0 Introduction 2.1 Characteristics of building that address sustainability issue A) Low-E double glazed glass window B) Green roof C) Motion sensors D) Building orientation (Plan, Sections)
Page Number
1 1 2 4 5 5 6
3.0 CLIMATE DATA 3.1 Introduction 3.2 Urban Heat Island (UHI) 3.3 Climate Data of Singapore 3.4 Graphical Analysis
8 8 9 9
4.0 WIND STUDIES 4.1 Wind frequency chart 4.2 Annual wind rose diagram 4.3 Psychometric chart
11 11 12
5.0 SUN PATH STUDY DIAGRAMS 5.1 Daily Sun Path in April 5.2 Daily Sun Path in June 5.3 Daily Sun Path in September
13 13 14
6.0 PASSIVE DESIGNS 6.1 Building Orientation 6.2 Internal Environmental Climate Control 6.3 Green roof
15 16 19
7.0 CONCLUSION
21
8.0 REFERENCE
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1.0 Building Profile Building Name Architect Location Building Type Square Footage
: Nanyang Technology University School of Art, Design and Media : CPG Consultants Pte Ltd : Singapore : Educational Building : Appox 215,000 sq ft
Figure 1.1 NTU School of Art, Design and Media (http://www.blueseed.co)
1.1 Description The School of Art, Design and Media (SADM) at Nanyang Technology University in Singapore is a 5-storey facility that highlights the transparency and connectivity in both interior spaces and exterior environment which engages the human senses. (Figure 1.1) The school was built on the wooden valley of the campus which was originally the „green lung‟ in the campus‟ master plan. Therefore, it was designed with the landscape moulding the school‟s building form. The building is strategically located in between the campus main academic blocks and the dormitory clusters which make it highly accessible to all students. The construction of the school is completed in June 2006 and has won the USA School Construction News Award (Honours) in 2007.
1.2 Highlights of Passive Design
1. 2. 3. 4. 5.
Building is longitudinally oriented to east-west Intertwining green roof that blurs the line between landscape and building Double glazed windows on the exterior curtain walls Sunken, almond-shaped courtyard with water features Low maintenance with raw finishes in both indoors and outdoors 1
2.0 Introduction Nanyang Technological University, a prestigious university which sits on 200 hectare of garden campus near Jurong West has been developing its campus facilities to improve its standards and also accommodate increasing number of students. (Figure 2.1) At the same time, these efforts were introduced alongside with the implementation of sustainable design.
Figure 2.1 Location map of NTU campus. (http://www.maps.google.com)
The School of Arts, Design and Media (SADM), established in 2004, has required a permanent place of belonging hence leading to a construction of a new building. The school is currently situated in one of earliest green and sustainable building that was introduced to its campus grounds. The SADM building is located at the junction of Nanyang Ave and Nanyang Drive which is around the centre of the campus. The SADM building particularly stands out from the other building that surrounds it because of its unique sloping green roof made it the new icon of Nanyang Technological University.
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Figure 2.2: The campus map of NTU and location of the school of ADM. (http://www.ntu.edu.sg)
The SADM building is located at a wooden valley that was initially the green lung of the campus according to the original intention of the master plan. (Figure 2.2) But due to the lack of land, desparate measures have been taken to build upon the green lung of the campus. Because of that, the design team moulded the structure to enable the existence of the original greenery and at the same time coexist together with the new building. As a result, a building with three boomerangs shaped curve that is covered by turfing. (Figure 2.3)
Figure 2.3: The most prominent green feature – green roof (http://www.greenroof.com)
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The continuity of spaces within the building exists both in the interior and the exterior. In the interior, effort was given into maintaining the traditional linear system. Besides that, the corridors within the building are interconnected which provides seamless circulation within the multiple wings present. Glass is used to open up the interior spaces to the surrounding environment which further enhances the concept of connectivity not only within the building itself but also with the exterior. Besides that, it also has the effect of mirroring the surrounding environment which further blends the building into its surrounding context. (Figure 2.4) At the exterior, the grass turf on the roof connects one and another visually and at the same time provides communal area for students to conduct outdoor activities. Figure 2.4 Reflections from both glass faรงade and reflective pool.
2.1 Characteristics of building that addresses the sustainability issue:
A) Low-E double glazed glass window. This type of window is used on the building in order to allow natural daylight to penetrate the building and reduce the amount of heat that enters the building.
Figure 2.1.1: Ceiling-to-floor height glass curtain wall at the lobby
Figure 2.1.2: Close up shot of the double glazed glass.
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B) Green Roof One of the most prominent green features found from the building is its green roof. The grass regulates the air quality and at the same time insulates the building from heat gain. Besides that, it acts as a communal area for the students. Zoysia Matrella had been used because it has a complex web root which makes it one large carpet at the same time tropical weather allows optimum growing condition for the grass.
Figure 2.1.3: View from the rooftop.
C) Motion sensors The sensor can be found at the washrooms and corridors. This system enables the lights to be automatically switch on and off by detecting the surrounding motion. When there is no activity, the light will turn off to save electricity.
Figure 2.1.4: View of the corridor with the motion sensor lighting system.
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D) Building Orientation. The building is orientated with major openings facing north and south. This method reduced the heat gain of the building through the openings such as glass windows. Roof plan
Sections
6
.
Figure 2.1.5: The almond-shaped courtyard in between the intertwining roof with water features.
Other green features that can be found from the school building include the CO2 sensor, refrigerant leak detection system, auto condenser tube cleaning system and rainwater collection system
Figure 2.1.6: The intersection point of the intertwining roofs with glass façade.
The construction of the building completed in year 2006. It has been awarded by the Green Mark Platinum Award in year 2011 under the category of “Existing Non- Residential Building”
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3.0 Climate Data
3.1 Introduction Singapore sits along the equator, therefore it has the tropical rainforest climate which is hot and humid throughout the whole year. The weather is uniform with frequent rainfall and high humidity. The climate of Singapore can be divided into two seasons: the northeast monsoon and southwest monsoon season. They are separated by inter-monsoon periods which are from January to early March and from June to September. Even though Singapore does not have four seasons, it does have its coolest period during December to January and hottest period from late April to June.
3.2 Urban Heat Island (UHI) A metropolitan area which is warmer compare to its surrounding rural areas due to human activities conducted.
Figure 3.1.1 Satellite image of temperature between rural and urban areas in Singapore. (http://www.bca.gov.sg/ResearchInnovation)
The image shows that the red zone is the higher temperature areas which can be observed from the exposed hard surfaces in the urban context whereas the green zone is the lower temperature areas such as large landscape area.
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3.3 Climate data of Singapore Annual average temperature
: 28°C
Average highest temperature
: 33-35°C
Average lowest temperature
: 23-26°C
Average annual precipitation
: 2270.8mm
Average percentage of humidity
: 84%
Average annual sunshine
: 2022 hours
Average wind speed
: 7.1kph
3.4 Graphical Analysis
Figure 3.4.1: Average temperature (ºC) Graph for Singapore (http://www.worldweatheronline.com)
The graph shows the average temperature in Singapore. (Figure 3.4.1) The average high temperature is 32°C whereas the average low temperature is 26°C. Singapore has a higher temperature compare to Malaysia due to its urban heat island effect. Upon conducting study and research, a conclusion can be made where the students of the School of Art, Design and Media rarely uses the outdoor spaces of the building which includes the green roof and he central courtyard due to the high temperature during daytime.
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Average Rainfall Graph (mm) in Singapore 300
Amount of Rainfall (mm)
250
281 253
239
200
173
187
201 183
172
168
May
Jun
180 159
172
150 100 50 0
Jan
Feb
Mar
Apr
Jul
Aug
Sep
Oct
Nov
Dec
Figure 3.4.2 Average rainfall graph (mm) in Singapore
The graph states that the average rainfall in Singapore which is 197mm. (Figure 3.4.2) The highest average rainfall in Singapore is during December whereas the lowest average rainfall is in July. The high rainfall volume might have influenced the design of the buildingâ€&#x;s roof. The roof is most probably design with an angle to allow the water to flow off the roof smoothly.
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4.0 Wind Studies
Diagram 4.1: Singaporeâ€&#x;s annual wind rose
Based on diagram above, wind flow in Singapore is present in all direction. (Diagram 4.1) However, Strong wind such as those which exceeds 20 km/h is presented more frequent from the northeast (NE) direction.
Diagram 4.2: Singaporeâ€&#x;s annual wind rose in relation to SADM building
The building is well sheltered from strong wind currents. (Diagram 4.2) However, slow wind is brought into the building compound to provide ventilation at areas such as the courtyard. 11
Diagram 4.3: Singapore psychometric chart
The psychometric chart shown above states the zone where thermal comfort is achieved. (Diagram 4.3) However the chart also shows the Air Humidity (AH) level is much higher from the comfort zone which means the weather in the region is too humid and might lead to discomfort of user.
Diagram 4.4: Wind flow on building
Figure 4.1: Interior courtyard of the building
Due to its function as a university building, Nanyang University practices Infiltration (HVAC) as the main means of ventilation. (Diagram 4.4) However, some of the spaces of the building are naturally ventilated. Among the spaces is the interior courtyard as well as the exterior walkways.(Figure 4.1)
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5.0 Sun Path Study Diagrams Diagram below shows the shadow casted by the building at different interval within a day (9:00am, 12:00pm and 4:00pm) in critical months which are April, June and September. 5.1 Daily Sun Path in April
0900 hrs
1200 hrs
1600 hrs
As seen in the first and third diagrams, the shadows casted at these time intervals were able to shade a portion of the building itself which is able to reduce certain amount of heat gain through the glass curtain walls. 5.2 Daily Sun Path in June
0900 hrs
1200 hrs
1600 hrs
The shadow casted by the building is quite similar to the diagrams simulating the daily sun path of April. However, it is clearly seen that the outdoor spaces such as the central courtyard and the roof garden are not well shaded which turns them totally uninhabitable especially during noon due to the extreme heat as mentioned by students and staff during interviews conducted.
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5.3 Daily Sun Path in September
0900 hrs
1200 hrs
1600 hrs
The lack of any shading devices has left many parts of the building exposed to the sunlight which contributes to the heat gain of the building. The sole use of double glazed windows would be insufficient to reduce entirely the heat gain of the interior spaces. This leads to the requirement of more artificial ventilation to provide a conducive learning and working environment.
Figure 5.1 Annual Sun path of NTU School of Art, Design and Media
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6.0 Passive Design There are a few of passive designs found in the School of Art, Design and Media (SADM) of Nanyang Technological University to reduce energy and to comply it with the Green Mark’s standard and regulation. We will be looking into three prominent passive designs of the building as follow;
6.1 Building Orientation The development of NTU is brilliant as it is oriented east-west longitudinally with high exposures of curtain wall facades at the north and south to allow minimal heat penetration. (Figure 6.1.1) It is also able to maximize the interior daylight with indirect sunlight from east and west. This is one of the green feature which helps to reduce the usage of indoor lighting system during daytime and save up a lot of electricity for almost 120,000 kWh per year , enough to power up 27 units with 4room of HDB (Housing and Figure 6.1.1 Roof plan of NTU School of Art, Design and Development Board of Singapore) flats Media a year. (Corporate Communications Office, 2011) According to the analysis, the orientation puts the opening of the courtyard toward the main circulation which makes the building more welcoming to the visitors and users as well.
Figure 6.1.2 View from top platform of the roof.
Figure 6.1.3 View from staircase beside the roof.
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6.2 Internal Environment Climate Control Soft Coat Low ‘E’ Double-glazed windows consists two glass panels in a same frame and both of them are separated by a 20mm space bar. (Figure 6.2.1) It is to maximize the efficiency of heat penetration from the sun. Argon gas which has low thermal conductivity fills up the 20mm spaces. (Gibson, n.d.) Therefore, high performance double-glazed windows are used to install in SADM building to maximize the visibility in the interior spaces and minimize the heat penetration at the same time. (Chen, 2009) Through convection process, the trapped gasses in between the glasses act as insulator and slow down the heat transfer.
Figure 6.2.1 Closer shot of the double glazed glass.
Inner Glass Polysulphide Secondary Seal
Air Space
Desiccant Air Space
Outer Glass
Outer Glass
Inner Glass Diagram 6.2.1 Details of the double glazed glass
The air space reduces heat transfer by conduction (air is a poor conductor) and convection (air gap is too narrow for efficient convection currents). 16
Based on the studies, the installation of double-glazed windows successfully helps to reduce the heat gain of the building, hence lack of the usage of air conditioning in indoor because the interior spaces remain at room temperature. The installation of Low E double-glazed windows allows the users to feel comfortable in the building even when they sit nearby the window areas during daytime. (Figure 6.2.3) Double-glazed windows help to reduce noises and provide more peaceful interior spaces for students to study especially the library area. (Figure 6.2.4)
Figure 6.2.3 View from courtyard
Figure 6.2.4 Library area with curtain wall faรงade to allow visible light to light up the interior space.
Heat Part of the heat is insulated from the double glazed window.
Visible light
Infared Sunlight
Visible light is allowed to penetrate into the indoor to light up the spaces without much of heat.
Diagram 6.2.2 Heat and sunlight penetration analysis diagrams
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Furthermore, the material used for double-glazed windows frame in SABM building is aluminium. (Figure 6.2.5) Aluminium is much stronger than vinyl (PVC) and wood, making it to be an ideal material for window frames. (Figure 6.2.6) It can withstands high corrosion and last longer than other materials. It is also one of the environmentally sustainable materials with the highest recycling rates compared to other metals. All these researches conclude that aluminium window frames able to help the management to reduce the maintenance cost. Furthermore, curtain wall facades with Aluminium frames bring out the aesthetic value of the interior space and it looks more welcoming to the visitors and users because the overall view looks clean and simple.
Figure 6.2.5 Overview of floor to ceiling height curtain wall faรงade.
Weatherproof and age-resistant glass sealing
Figure 6.2.6 Close-up view of aluminium frames.
Easy-clean structure, attractive and elegant frame with clean lines and appearance.
Energy-saving and noise-insulating multi-chamber frames Large metal reinforcements in accordance with structural requirements. Diagram 6.2.3 Details of double glazed glass.
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6.3 Green Roof
The intertwining green roof top designed by CPG Consultant is one of the most significant features found in SABM building. (Figure 6.3.1) 100% of SABM building’s roof is covered by turfing. Zoysia Matrella, or Manila grass had been used as the turfing for the building roof because it has a complex web root which makes it one large carpet. (Figure 6.3.2) The management team installs moisture retention under the soil to assure the grass to be in damp condition always even when the roof is exposed under the hot sun. (Diagram 6.3.1) This method helps to maintain the greenness of the grass throughout the year. The turfing able to modulate the air quality by cutting down the quantity of C0 2 through daily photosynthesis and at the same time insulates the building from heat gain. It reduces Urban Heat Island (UHI) effect through daily dew and evaporation cycle. In addition, Turfing able to prevent the roofing membranes from exposing to temperature fluctuations and this can serve to avoid micro-tearing or ultraviolet irradiation. Besides that, drainage system is installed at both sides of the green roof to facilitate the flow of the rain water and prevent the accumulation of rain water on upper side of the roof. (Diagram 6.3.2) Through the studies earlier, it shows Zoysia Matrella grass is a beneficial selection to be the roof turfing because the tropical conditions in Singapore allows optimum growing conditions for the pasture. Furthermore, the consolidation of architecture and nature takes an artistic perspective and promotes green culture in the campus itself.
Figure 6.3.1 Overview of the green roof.
Figure 6.3.2 The intertwining roof view.
Figure 6.3.3 Drainage can be seen beside the green roof.
Figure 6.3.4 Another view of drainage system on top of the roof. 19
Pictorial meadows green rood seed mix Green roof substrate Filter layer Drainage layer Protection mat Waterproof membrane
Insulation Vapour Control Layer Plywood Deck
Diagram 6.3.1 Layerings of the green roof
Drainages to ease the water flow from roof. Diagram 6.3.2 Drainage system on the green roof
In addition, there is a staircase along the edges of the roof on the right side providing pathway to the visitors, students and others to explore the green roof and enjoy the nature at the same time. (Figure 6.3.5) This provide a solution of losing an open space indirectly, offering the users an extra informal gathering spaces and allow the people to circulate every part in the building. (Figure 6.3.6) This helps the people to appreciate nature within architecture more.
Figure 6.3.5 Staircase provided for user to access the roof.
Figure 6.3.6 Students from Taylors University performing site studies in SADM building.
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7.0 Conclusion
As one of the earliest green buildings that was introduced to the land of the National Technological University of Singapore, the building still stand tall as the trademark of the university. The innovative green roof that was introduced to the building not onto provides insulation for the building but at the same time transforms the roof into an inhabitable space. Even so, there are still flaws on the early day design as the high temperature was not taken into consideration and hence making the roof garden too hot to carry out any activities during noon. Besides that, the use to double glazed glass has cut down the heat gain of the building through the glass curtain walls that was present throughout the entire building in bug numbers. However, there was very little sun shading devices to be found on the building. Considerations can be made to apply sun shading devices to the building to further reduce the heat gain through the window panes during the hot afternoons throughout the year. The interesting form of the building had been the trademark for the National Technological University of Singapore since it's completion in 2006 and one of the early role models for the blooming trend of green buildings in being constructed in Singapore. The building had brought much impact to the construction industry in Singapore and is well worthy to be awarded the Green Mark award by the authorities.
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References Building and Construction Authority. (2011) BCA Awards 2011. Retrieved 8th May 2014 from http://www.bca.gov.sg/greenmark/others/gm2011.pdf Chen, A. (2009). View From the Roof: This new school of art, design, and media at Nanyang Technological University preserves open space, while serving as a green icon for the community. New York: GreenSource Magazine. Retrieved from 8th May 2014 http://greensource.construction.com/projects/2009/05_Nanyang-TechnologicalUniversity.asp Corporate Communications Office. (2011). NTU wins Platinum Award from BCA for sustainable design. Nanyang Technological University. Retrieved 8th May 2014 from http://news.ntu.edu.sg/pages/newsdetail.aspx?URL=http://news.ntu.edu.sg/news/Pages/N R2011_May19.aspx&Guid=a8e4c01d-3d26-484f-86ed-1a25cee9dbcf&Category=All CPG Consultants. (2014) Nanyang Technological University: School of Art, Design and Media. Retrieved 8th May 2014 from http://www.cpgcorp.com.sg/CPGC/Project/Project_Details?ProjectID=1022 France, D. C. (2014). How Double Glazing Works. GCSE PHYSCIS. Retrieved 8th May 2014 from: http://www.gcsescience.com/pen16-double-glazing.htm Gibson, C. (n.d.). What You Need to Know About Double Glazing. Retrieved 8th May 2014 from: http://www.homeimprovementpages.com.au/article/what_you_need_to_know_about_dou ble_glazing Michelle K. (2011) Thinking Out Of The Box. Retrieved 8th May 2014 from http://www.cpgcorp.com.sg/CPGC/Content/Publications/20110900_PerspectiveThinking_out_of_the_box.pdf Mike (2011) Tower of Sustainability. The Propertizer. Retrieved 8th May 2014 from http://thepropertizer.blogspot.com/2011/05/tower-of-sustainability.html Nanyang Technological University. (2009). The School Iconic Building. Facilities. Retrieved 8th May 2014 from http://www.adm.ntu.edu.sg/AboutADM/Facilities/Pages/Building.aspx Nanyang Technological University. (2011) NTU wins Platinum Award from BCA for sustainable design. Retrieved 8th May 2014 from http://news.ntu.edu.sg/pages/newsdetail.aspx?URL=http://news.ntu.edu.sg/news/Pages/N R2011_May19.aspx&Guid=a8e4c01d-3d26-484f-86ed-1a25cee9dbcf&Category=All Shaily R., Vipul S. (2011) Design Guide: Horizontal Shading Devices and Light Shelves. Assignment No. 3. Retrieved 8th May 2014 from http://www.public.asu.edu/~kroel/coursesb/coursesa/www558/Shaily%20Vipul%20Assig nment%203.pdf National Environment Agency. (n.d.) Singapore’s Climate Information and Data. Retrieved 8th May 2014 from http://app2.nea.gov.sg/weather-climate/climateinformation/singapore%27s-climate-information-data 22