Asian Architecture [ARC60403] Project 2: case study
A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Name
: Tan Zi Jian
Student ID
: 0318291
Lecturer
: Nurul Alia Ahmad
Submission date : 24 November
A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Table of Contents Abstract 1. Introduction 1.1 Issue 1.2 Objectives 2. Case study 3. Thermal Comfort 3.1 An overview of thermal comfort 3.2 Factors that affect thermal comfort of residential house in Malaysia 4. Aspect to be considered to pay respect to how thermal comfort can be achieved 4.1 Site microclimate 4.1.1 An overview of site microclimate 4.1.2 Microclimate around House 484 4.1.3 Contextual strategies respond to site microclimate 4.1.3.1
House orientation
4.1.3.2
Overhang Roof
4.1.3.3
Openings
4.1.3.4
Wall
4.1.3.5
Ventilation system (compare with Malay hose)
5. Recommendation to improve thermal performance 6. Conclusion 7. Reference
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Abstract Architecture today has involved in a challenge of achieving thermal comfort with assistance of contextual factors. The aim of analyzing contextual design strategies adopted by House 484 is to determine the influence of site contextual factors around it towards thermal comfort. For this research paper, the analysis on site context around House 484 is carried out as a comprehensive information to facilitate the building. House 484 owns some of the remarkable features as a design approach to achieve thermal comfort. In assisting the validation of research, the process is enhanced by the conducted interview with the architect of the selected building. In order to achieve thermal comfort, this research paper will specifically highlight the contextual design strategies in term of design features according to sun path and wind direction. For gaining further insight into the research, deliberation on site context is vital which can showcase the contextual design features, in which the House 484 at Country Heights Damansara has been studied. To cooperate with an east-facing site, the faรงade of House 484 is design to be opened and wide to allow morning sunlight to be captured together with the happenings of cross ventilation. To avoid user from getting thermally unpleased, the west faรงade is only allow to contain minimal fenestration which is considered as closed. Actively, both solar water and photovoltaic system which are benefited by the potential landscape on site are carefully applied to become one of the cooling element. The ventilation system of House 484 is actually having similarities with traditional Malay house which is deemed as typical architecture to confront the tropical weather. The large extensive overhangs is well located in the design to assist the house orientation to provide high quality shading effect and cater the prevailing wind as much as possible. Furthermore, large and plenty of 3
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara openings are another feature akin to Malay house as well. On the whole, it has come to a conclusion that House 484 has well demonstrated how the thermal comfort can be effectively achieved in term of contextual design strategies.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
1. Introduction 1.1
Issue The emanation of thermal comfort challenges does call out for a
tremendous reformation or revolution of architectural design strategies. The obstacles for a tropical climate country to achieve thermally comfortable indoor environment will definitely be the hot and humid weather conditions. The insignificant difference between outdoor and indoor temperature should be a vital factor for an architect to pay respect to, particularly in Malaysia which the tropical weather cannot be ignore. In spite of the extensive potential in House 484 for reducing heat gained, Malaysia has been determined as one of the hottest country. Several factors have dedicated to the presence of a thermally uncomfortable building stuck in the country, including the facilities around it and lack of stringent consideration of contextual elements.
1.2
Objectives Manifold contextual design have been established and evolved for the sake
of solving the issue of achieving thermal comfort. The objective of this paper is to appraise the utility of applying chosen contextual design strategies in order to promote thermal performance and reduce heat gained in a building in hot and humid climate settings. For the purpose of this investigation, a real case building was chosen and several design strategies were considered.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
2. Case study Looking back to the past local architecture which display that contextual design strategies was broadly used during the period that air-conditioning had not been invented. Among these strategies in the vernacular architecture was the House 484 which features the large extension roof. House 484 is a contextual architecture that nestled admits the winding pathways and fluctuant landform of Country Height Damansara. House 484 sits on an extremely challenging topography and is widely exposed to wind and sunlight. This challenge was took as a benefit to design the house with distinct tropical contextual design strategies to improve thermal performance.
For the purpose of confronting the site limits, several horizontal planes, layered and sheared to build spaces that concatenate with the landscape, Furthermore, contemporary tropical design is widely applied to residential building these days which successfully improved the thermal performance of spaces and architecture quality. The importance of tropical architecture lies beyond its regional and climatic concerns.
House 484 had gained a gold award winning architecture design which is popular for its interior design and nice architecture and particularly the design feature adopted to make the home fit nicely on the site.
House 484 is selected for my case study and the investigation will be reinforced by the following questions:
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Question 1: How the architect strategizes House 484 to accommodate the microclimate at Country Heights, Damansara?
Question 2: What kind of design features that applied in House 484 in order to incorporate with the surrounding environment and achieve thermal comfort?
Question 3: How are the ventilation system applied in House 484 in achieving thermal comfort? Explain by using the similar ventilation system in traditional Malay House
Question 4: How was House 484 orientated according to site condition to reduce heat gain?
Question 5: How the architect makes use of building components in order to achieve thermal comfort?
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Figure 2.1: Concept Mapping 8
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
3. Thermal Comfort 3.1 An overview of thermal comfort Thermal comfort is not recognized as an objective affair that it cannot be specifically defined since plentiful of environmental and personal element have to be considered in the identification of individual comfort experience. As stated in “British Standard BS EN ISO 7730”, “thermal comfort is that condition of mind which expresses satisfaction with the thermal environment.” Apart from that, in agreement with ASHRAE Standard 5, “thermal comfort in a building is considered success when thermal environmental conditions is acceptable by 80% of the occupants in the space.”
3.2 Factors that affect thermal comfort of residential house in Malaysia As reported by ASHRAE Standard 55 “thermal environmental conditions for human occupancy”, ‘”There are large variations, both physiologically and psychologically, from person to person. It is difficult to satisfy everyone in a space. The environmental conditions required for comfort are not the same for everyone.” Hence, it is not an easy job to identify an ideal temperature that able to satisfy the desire of every occupant. However, thermal comfort is generally influenced by 6 primary factors which are classified into two domain: environmental factors and personal factors. Environmental factors consist of radiant temperature, air speed, relative humidity and air temperature. Whereas, personal factors consist of individual metabolic rate which depend on the human activity and the clothing status. The dominant elements that
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara influences thermal comfort in case study can be recognized as air speed, air temperature and the sunlight intensity.
Figure 3.2.1: table of thermal comfort level (Source: Passivhauspt, 2015)
According to MetMalaysia, Malaysian meteorological department, there is consistently high temperature all over the year in Malaysia along with the high relative humidity which is varying form 70% to 90%.Therefore, maximization of the air flow and decreasing of the humidity’s strategies are much appreciated. As Figure 3.2.1 shown, the ideal indoor air temperature vary for thermal comfort should be within 20 ºC to 23 ºC. 10
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara Furthermore, wind direction and air speed have contributed to the existence of thermal comfort. Thermal comfort can be achieved by heat gained or heat loss due to the difference between human temperature and moving air temperature. The variance within outdoor and indoor temperature playing an important role in affecting thermal comfort which allows people to go through the gap constantly in an inconsistent way. As Malaysia is an equatorial country, commonly light but long period wind can be experienced. This gives an opportunity to have big opening in the building design for well cross-flow of air in order to increase thermal performance.
Figure 3.2.2: local thermal discomfort caused by radiant temperature asymmetry (Source: stbworkshop, 2015) ASHARAE Standard 55 has stated, “People are more sensitive to the asymmetric radiation caused by a warm ceiling that caused by hot and cold vertical surfaces which can be shown in Figure 3.2.2�. There will be a radiant heat transferred between objects which are able to emit and absorb radiant heat. Cooler object will gained the radiant 11
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara heat from the hotter object, this net flow has produced the radian temperature. This net flow will only be saturated and stop when thermal equilibrium is achieved which is the objects contain same amount of heat energy. This kind of net flow between human and the environment are summed up by plane radiant heat flow which is provided by plane radiant temperature and the information of moderate temperature will be provided by the radiant temperature.
4. Aspect to be considered to pay respect to how thermal comfort can be achieved 4.1
Site microclimate
4.1.1 An overview of site climate Microclimate is playing a vital role of being design solutions which pay respect to the contextual element. Microclimate represent the specific climatic situation of an area or a particular spot on site. Microclimate includes humidity, wind exposure, sun exposure and temperature in the selected area. Every single building has its own microclimates which make it be uniquely designed. As for a designer, microclimate should always be considered while planning the activities of occupants. For instance, the spaces intend to obtain sun exposure should be placed at the sunniest area whereas a space need of least are movement ought to be placed at a suitable area which is able to prohibit it from getting windage. Moreover, the most active spaces should be well design and located to cooperate
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara with the site context in order to create a more pleasurable and satisfying, especially thermally enjoyable space which can last for a long time.
The spaces quality can be seriously influenced by a well operated contextual architecture meanwhile it enrich the surroundings as a reflection. Architecture will not be altered by site context, there are co-existence and resonance between both of them. Hot and humid weather conditions have Malaysia classified as a tropical country. To overcome the climatic problem, design strategies should be perfectly working with the contextual factors. One of the famous modern architect, Frank Lloyd Wright advocated, “No house should be ever be in a hill or on anything. It should be of the hill, belonging to it hill and house should be live together, each the happier for the other�
4.1.2 Microclimate around house 484 The east side of House 484 is the most moderate zone as it is able to receive morning sunlight, yet being shaded in the afternoon. Thus, it is an ideal area for morning and afternoon outdoor activities. However, west side bathed in sunshine during afternoon but completely profited from morning shade. If afternoon activities was planned at this area, it would be acting against the contextual factors and negative impact will happen to the architecture.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
4.1.3 Contextual strategies respond to site microclimate 4.1.3.1 House orientation According to the site microclimate, sun exposure was the primary consideration due to the site was fully exposed. Sunlight has an affection on shadow pattern and air temperature which straightly affect the thermal comfort. A designer should aware of his or her environmentally responsibility and have a penetrating understanding of how the contextual factors work with the design. Therefore, sun path analysis should be done to assist the design process. The sun path diagram below is displaying how the sun path being considered and the relative contextual strategies were applied to achieve thermal comfort.
Figure 4.1.3.1.1 Sun Path Diagram at House 484 Country Heights, Damansara
(Source: Intechopencom, 2015) 14
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara The diagram is showing every single side of House 484 has its distinct microclimates which resulted by the specific site conditions. Hence, the orientation of House 484 is able to convey us its contextual consideration.
Figure 4.1.3.1.2: Ground Floor Plan (Source: Ar Chan Mun Inn)
Most activities area
Least activities area
The ground floor plan can tell the architect purposely orientated House 484 to be extremely well blended with the sun. Most of the areas are designed to be facing east direction and effectively avoid the house from sunlight penetration without any cooling mechanism but it still manage to achieve thermal comfort. West side was still be employed
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara and concrete, which is an environmental friendly material was used to enclose the particular area to improve the thermal performance as well. As the ground floor plan shown, the enclosed west side is selected for the location of utilities room of the house whereas more active spaces such as external terrace, swimming pool and living room are design to place at the east side for the achievement of optimal thermal comfort. The bedroom is north-south orientated which is worthy to be mentioned. It completely reduced the cooling load since the aid of the orientation blocks all the daylight coming in and a cozy and restful space was provided for the occupants.
4.1.3.2 Overhang Roof
Figure 4.1.3.2.1: Shading in different time period (Source: Ar Chan Mun Inn) 16
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara In agreement with Ar. Chan, the entire interior spaces will be well shaded during 12:00 noon under the assistance of the large overhang roof which was designed to work with the orientation to increase the thermal comfortability. It mainly function to prevent the penetration of afternoon sunlight to keep the building cool and against gaining extra heat. Besides, Ar. Chan mentioned about the size of the overhang roof was precisely calculated in the design process to have certain walls being shadowed. Wall is one of the building component that having direct contact to the occupants. The overhang roof provide contribution in reducing the heat conducted by the wall for the purpose of maintain ideal indoor temperature. Once a wall is shadowed, the material selection will be less critical to produce a thermally pleasurable space. Beside of shading, the large overhang roof was designed to be extensively extended to cater the maximum prevailing wind as Figure 4.1.3.2.2 shown.
Figure 4.1.3.2.2: Overhang roof cater prevailing wind (Source: Ar Chan Mun Inn) 17
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
4.1.3.3 Openings
Figure 4.1.3.3.1: wind direction distribution -Location: Kuala Lumpur (Source: windstatics, 2015)
Figure 4.1.3.3.2: wind frequency -Location: Kuala Lumpur (Source: windstatics, 2015)
Figure 4.1.3.3.3: Wind directions on site (Source: Ar Chan Mun Inn)
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Figure 4.1.3.3.4: Opeing also allow wind coming from higher position to lower position (Source: Ar Chan Mun Inn)
From the diagrams above, we can tell that the prevailing wind is breezing from east to west on site. However, wind flow in every direction all over the year according to Figure 4.1.3.3.1. Hence, the prevailing wind is able to complete the cross ventilation with the aid of openings to bring away the heat gained from the occupants inside. There are plentiful of openings in House 484 all over the vital area for ventilation. House 484 is having a completely opened and ventilated east faรงade and it was primarily consist of glass windows obtain the warming sunlight. The west faรงade was treated with a totally different measure which contain minimum fenestration. These kind of design also create the pressure difference between inlet and outlet. Much air enter the building by the openings at the east side with a higher pressure and moving outward through the smaller and lesser openings at the west side with a lower pressure. Windows are kept open during the day to allow more air movement happen to lower down the temperature of the indoor spaces.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Figure 4.1.3.3.5: Air flow in House 484 (Source: Ar Chan Mun Inn)
4.1.3.4 Wall
Figure 4.1.3.4.1: Clear double cavity wall (Source: drawn by Tan Zi Jian)
Figure 4.1.3.4.2: Triple Laminated Glass (Source: Drawn by Tan Zi Jian)
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara A clear double cavity wall consists of 100mm thick inner wall and a 300mm thick outer wall with a 60mm thick clear cavity in between was utilized in House 484. The reason of applying clear gap instead of thermal insulated layer is because there is no big difference between the indoor and outdoor are approximately the same since Malaysia is a tropical country. The double cavity act as a blockage to prevent the outdoor heat from transferring into the interior spaces which help in improving thermal performance. Triple laminated with low-e coating is selected to install on the wall to avoid ultraviolet ray from directly going through the transparent material. Due to the wavelengths can be allow to penetrate are different, daylight can be admitted while large amount of heat is reflected back to exterior. Hence, thermal comfort is achieved due to the maintenance of interior temperature.
4.1.3.5 Ventilation system (compare with Malay house) To encounter with the hot and humid weather condition in Malaysia, House 484 own its particular ventilation system which is contributed by the orientation, openings and site context as mentioned above. A comparison between House 484 and local traditional Malay house was done to have a deeper understanding of ventilation system.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Figure 4.1.3.5.1: Malay house ventilation system (Sorce: Nzdlorg, 2015)
For a traditional Malay house, there are some feature which contribute to ventilation. Plentiful of openings are randomly placed at the opposite wall to produce largest air movement which cause the maximum ventilation to bring away the heat. Steep pitch roof is one of the feature of the traditional Malay house, and more importantly, it is a high porous roof. This kind of roofing style encourage the heat gained from interior escape along with the rising air movement and aim to achieve cooling effect in the interior. Furthermore, traditional Malay house are normally raised by the stilts to cater the rapid speed. The interior layouts are randomly arranged which maintain the wind velocity as well.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara After the natural ventilation in both House 484 and Malay house were studied, the surrounding context, location of the openings, size of opening become the primary considerations in an architectural design which is serving the ventilation to achieve thermal comfort. Here is a table that display the comparison between the ventilations in both buildings.
Traditional Malay House Location opening
and
Layout
size
House 484
of On relative opposite walls; Depend of site location and Broad but usually full length the spaces arrangement, opened bigger and more at east side, smaller and lesser at west side to create air pressure.
Randomly arranged, there Well planned to face and is no barrier to reduce the catch the first hand wind wind velocity
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
Wind velocity gradient
As it is built on stilts, sitting Plentiful of opening and use on higher level capture high of the air pressure to velocity winds increase wind velocity
Ventilation of roof space
Ventilation by the provision Overhang roof to cater the of ventilation joints and wind as much as possible. panel in the roof construction
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
5. Recommendation to improve thermal performance
Figure 5.1: Proposing stack ventilation in House 484 (Source: Drawn by Tan Zi Jian)
Due to the height difference given by the natural hill, stack ventilation can be happened in House 484 since the cross ventilation is frequently happening inside. However house 484 do not have enough openings at the higher position which all of them are concentrated at the building body. According to MS 1525, stack ventilation is ventilation due to air density differences to provide air movement across a space. Indoor air rises when warmed by internal loads such as people, lights and equipment, creating vertical pressure gradient within enclosed space. More opening should be installed on the both sides of the wall in order allow the entered air bringing the heat collected and rises to escape through the additional high openings. This will increase the circulation within the space. House 484 contain a large 25
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara volume and a great ceiling height, stack ventilation is allowed to happen more effectively and this increase the air movement in the space to obtain thermal comfort.
Figure 5.2: Process of stack ventilation (Source: Nzdlorg, 2015)
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
6. Conclusion In a nut shell, the contextual design strategies applied in House 484 contribute in rejecting or blocking or bringing solar heat gain away along with keeping the building cool against the heat. Most of the cooling load is not depend on the mechanism but the contextual strategies applied. Contextual design strategies relies on the climatic conditions of the spot, hence they should be designed and planned accordingly. The investigation has proved that various many aspect have been considered in designing the site to be much responsive to the nature. With every contextual design strategies applied, the architect manage to build an environment that is functionally and more importantly, thermally pleasurable for the occupants. Hence, House 484 is considered a thermally comfortable building which pays much respect to the contextual factors with the proofs of the strategies implemented.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara
7. References Dr. Louise Jones, LEED AP, IDEC, ASID, IIDA. (2008). Environmentally Responsible Design: Green and sustainable design for interior designers. 1st ed. John Wiley & Sons, Inc., Hoboken, New Jersey. A large amount of information about provided by the worldwide experts can be found in this book. It cover all the details about environment responsive design features with the aid of relevant case studies, photos and diagrams. Apart from that, it discuss about the reason of why a good architecture should be site responsive. As a conclusion, this book have me learnt more about “environmental responsive design� Norman K. Booth and James E. Hiss (2002). Residential landscape architecture: design process for the private residence. 3rd ed. Pearson Education, Inc., Upper Saddle River, New Jersey 07458. The book is conveying a message of how the quality fundamentals affects residential design. Concepts and basic principles are introduced as the preparations of designing a residential building. A lot of knowledge about contextual design strategies I gained by reading this book and it give me a clearer direction about the how to merge the contextual factor in an architectural design.
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A study in contextual design strategies to achieve thermal comfort in House 484, Damansara Keeler, M. (2009). Fundamentals of integrated design for sustainable building (1st ed., p. 338). Hoboken, N.J.: John Wiley & Sons.
Using an active learning approach, the authors Marian Keeler and Bill Burke explain the concepts of sustainable architecture and reinforce them through design problems, research exercises, study questions, team projects, and discussion topics. With this I learn more about sustainable design in a way more scientifically. The authors of this book, Bill Burke and Marian Keeler explain how they confront and tackle the design problems with much examples/ Team projects, study questions and research exercises have been provided. Along with this active learning process, I learnt about architecture is not just about design, we have to consider more of scientific factors which will be obstacle or support in the process of our designs.
Sustainability & the Environment. (n.d.). Retrieved June 8, 2015. The Significance of Sustainability to the Built Environment. (n.d.). Retrieved June 8, 2015. Neiser, L. (n.d.). The Importance of Sustainable Design. Retrieved June 8, 2015. Yeang, Ken, and Arthur Spector, Green Design, London: Black Dog, 2011. Print Yeang, Ken. Ecodesign. London, UK: Wiley-Academy, 2006. Print. 29
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