Building Services [ARC 2423]
PROJECT Contextual Architecture Study & Case Study Paper Binh Thanh House, Vietnam Lecturer: Ms Alia Name: Sen Yih Yiing
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Content 1.0 Abstract
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2.0 Introduction
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3.0 Façade Design Strategies For Tropical Climate
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7-‐ 9
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4.0 Types Of Façade Material To Achieve Thermal Comfort
5.0 Thermal Comfort Difference Ventilation Blocks Façade and Curtain Glazings Façade 6.0 Effect of the Orientation And Dimension of the Openings to the Thermal Comfort 7.0 Effect of the Site Context Elements to the Thermal Comfort of Binh Thanh House 8.0 Conclusion
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9.0 References
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10.0 Plagiarism Check
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1.0 Abstract
In tropical countries especially Southeast Asia, where dry and wet seasons are distinct and are high in humidity, ventilation is an important component to keep the building occupants to be thermally comfort, therefore, the façade design where most of the openings and glazings are in placed, could affect the efficiency of achieving optimum thermal comfort. In Vietnam, due to the crowded population, the dwellings are compactly constructed side by side in continuous elongated rectangular form , the design of the façade in terms of orientation, materiality and the surrounding site context are the factors to be discover to determine their effect to thermal comfort. Research techniques such as through literature reviews, relevant books and e-‐books, as well as websites and blogs to support the findings of my topic. As the chosen Asian building should be sustainable and contextual relevant, the Binh Thanh House is the suitable building to study as it inherited the traditional ventilation technique in Vietnam in a modern design, well use of site context elements such as sunlight, wind natural canal and greenery. Both sides of the dwelling’s façades are covered mostly by the concrete ventilation blocks, to enhance ventilation, prevent harsh weather such as wind and rain, and to act as sunlight fiter to minimize the exposure. Furthermore, the canal located beside the dwelling allows evaporative cooling and to control the temperature during both dry and wet season. The volumes of the dwellings are placed in and out alternately to create balconies which act as a sound and weather barrier and to keep the interior spaces at the core of the dwelling. The façade covered with ventilation blocks enhances ventilation and improves and introduces thermal comfort to the occupants. The ventilation blocks should be promoted in terms of functionality, aesthetic, durability and cost effiecient.
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2.0 Introduction
Figure 2.1 Front View of Binh Thanh House Source from http://static.dezeen.com/uploads/2013/08/dez een_Binh-Thanh-House-by-Vo-TrongNghia-and-Sanuki-+-Nishizawa_1.jpg
Figure 2.2 Interior of Binh Thanh House Source from http://votrongnghia.com/wpcontent/uploads/2013/06/BTH_04.jpg
The Bihn Thanh House is designed by Vo Trong Ngiah together with
Sanuki+Nishizaw. This 6 storeys residence is located at the developing-‐capital city of Vietnam, Ho Chi Minh City. It is designed to house two families of a couple in their sixties, their son, his wife and a child. The Bin Thanh House is orientated that the entrance is facing the dusty and noisy Ho Chi Ming street while the backyard is facing the Nghe Canal and Saigon Zoo. As to combine these two completely opposite condition of the site, the concept proposed by the architechs is to accommodate two different lifestyles in a tropical climate, which one of them is a modern lifestyle that accommodate a contant temperate experience by using air-‐conditioners and the other part is a traditional lifestyle that utilizes the scenery of water and greenery.
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Ventilation and lightning are both the most important and basic conditions for a good building, this is why the architects extensively uses the traditional shading device in Vietnam, the pattern blocks in their design. The pattern blocks covered a large area of the façade not only for shading purpose, but also to overcome the harsh weather of Vietnam such as heavy rain and monsoon season without fully covered the beautiul views of the site. The application of the pattern blocks enhance the aestheticness of the building’s façade, and most importantly, it is able express the cherishment of traditional architecture element in fusing them into modern living lifestyle and design.
Figure 2.3 Acceptable operating temperatures for naturally conditioned spaces, accoding to ASHRAE Standard 55-‐2004 Thermal comfort is defined by ASHRAE as “that condition of mind which expresses satisfaction with the thermal envoronment” (ASHRAE, 2004). The factors that affect thermal comfort are such as air temperature, air movement, humidity, mean radiant temperature, occupants metabolic rate and clothing. In advance, this paper will investigate the traditional ventilation method, which is utilising the ventilation block as the façade of the modernised residential building in the middle
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of the Ho Chi Minh City in terms to achieve thermal comfort by responding to the following research question: 1. How does the design of the façade enhance the thermal comfort of the building? 2. How does the type of the façade material affect the thermal comfort of the building? 3. What is the thermal comfort difference between utilizing ventilation blocks or pattern blocks and normal glazing on the façade of the building? 4. How does the orientation and dimension of the openings affect the thermal comfort of the occupants in the building? 5. How do the elements of the site context affect the design of the façade in enhancing the thermal comfort of the building?
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3.0 Façade Design Strategies For Tropical Climate As Vietnam is a tropical country which has 2 distinct dry and wet seasons which alternates half anually, the façade design which allow occupants to stay confortable and cool is an important criteria in deisgning the building. The design strategies for sustainable façades in tropical climate include solar control, reduction of external heat gains, cooling, as well as daylightning.
Figure 3.1 Façade as Shading Device in Binh Thanh House Source from http://cdn.architecturelab.net/wp-‐ content/uploads/2015/10/9685.jpg?bfbd62
In terms of solar control, a sustainable façade should function as a protection or shading device from direct solar radiation through self shading methods. As solar radiation in Ho Chi Minh city becoming a comfort issue in the city because of its fast development, cutting of trees and approaching towards urbanized city, the façade which can be use to control penetration of solar radiation would be an ideal strategy in building design. Next, the design of the façades should have the ability to reduce external heat gains. The design of the façade should be able to prevent infiltration or conduction of solar heat gain by utilizing well-‐ insulated opaque façade elemants or by using suitable shading device.
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Figure 3.2 Façade introduces daylighting and ventilation Source from https://i.homeadore.com/2013/09/010-‐binh-‐ thanh-‐house-‐vo-‐trong-‐nghia-‐sanuki-‐nishizawa.jpg
Moreover, a façade design which allows continuation of air flow to introduce
natural ventilation to the interior for cooling and permits optimum penetration od daylighting to illuminate the space inside the building are also the important aspects in façade design.
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4.0 Types Of Façade Material To Achieve Thermal Comfort
An energy efficient façade is defined as a design which could allow daylight
into a building, prevent excessive solar heat from penetrating into the building, able to store heat within the mass of the wall, has good insulation to prevent heat transfer, as a obstruction for the penetration of air moisture and enhances natural ventilation to cool the interior of the building, these factors are all closely related to the of material used in designing a sustainable façade.
There are commonly 2 types of façade: Figure 4.1 Opaque Façade in Panelli HPL (Left) Source from http://www.archiproducts.com/ en/products/75051/ventilated-‐ facade-‐pannelli-‐hpl-‐per-‐facciate-‐ ventilate-‐inpek.html
Figure 4.2 Opaque Façade in Contemporary Art Centre, Spain (Right) Source from http://www.architectural-‐ review.com/Pictures/web/b/w/f /RH2121-‐0052.jpg
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Opaque façade, contructed by layers of solid materials, for exaple mansory, stone, precast concrete panels, metal cladding, insulation, and cold-‐form steel framing. Punched opening or windows are also categorised as opaque façade.
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Figure 4.3 Glazed Façade in The Crystal, Copenhagen (Left) Source from http://pfnphoto.com/new/wp-‐ content/uploads/2013/06/20120 306-‐kopenhagen-‐0997.jpg
Figure 4.4 Glazed Façade in The National Marinetime Museum, London (Right) Sorce from http://cdn-‐ project.architectureweekend.co m/2f2b265625d76a6704b08093c 652fd79/photos/the-‐gherkin-‐ portada.jpg
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Glazed façade, consists of transparent or translucent glasing materials and metal framing components such as curtain walls or storefront facades.
Figure 4.5 Ventilation blocks facade in Binh Thanh House Sorce from http://images.adsttc.com/media/images /5215/6a8f/e8e4/4e4e/e300/00a8/large _jpg/pic18-‐facade-‐detail.jpg?1377135238
The type of façade applied at the Binh Thanh House is the opaque façade as it utilizes mansory and glass alternately to form a checker like façade. Other than that, the ventilation blocks on the façade also a type of opaque façade as they are constructed by using concrete with holes at the middle to allow ventilation.
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R-‐value (h-‐ft2-‐°F/Btu)
R-‐value (m2-‐°K/W)
0.10-‐0.4-‐ per inch
0.68-‐2.77
CMU, 8 in. (200mm)
1.11-‐2.0
0.20-‐0.35
CMU, 12in. (300mm)
1.23-‐3.7
0.22-‐0.65
Concrete
0.05-‐0.14 per inch
0.35-‐0.99
0.09-‐0.18 per inch
0.62-‐1.26
Concrete with lightweight 0.11-‐0.78 per inch
0.76-‐5.40
Material Brick
(sand and gravel aggregate) Concrete (limestone aggregate)
aggregate Stone (Quartzitic, and
0.01-‐0.08 per inch
0.10-‐0.53
0.03-‐0.13 per inch
0.23-‐0.90
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3.67
sand stone) Stone (limestone, mrble, granite) Mineral batt insulation, 6 in. (150mm) Table 4.1 Thermal resistance prperties of typical components for opaque building envelopes (Aksamija, 2013) The thermal resistance value (R-‐value) of a materila depends on the the type of insulation, thickness and the materila’s own density. The R-‐value is used to determine the insulating effectiveness of the material itself, the higher the R-‐value in (m2-‐°K/W), the higher the insulating effectiveness. Based on the table above, concrete based opaque building envelops are the materials with the highest R-‐value, which indicates concrete has the most effective insulation properties. As concrete is able to insulate the building from the surrounding weather, the thermal comfort of the occupants in the building can be achieved, as well as in Binh Thanh House.
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5.0 Thermal Comfort Difference Ventilation Blocks Façade and Curtain Glazings Façade In addition to the previous 4.0 Type of façade material to achieve thermal comfort, this section focus mainly in the thermalmal comfort difference between utilizing ventilation blocks or curtain wall glazing the façade design. Nowadays, modern design buildings tend to apply curtain walls extensively to their design as the curtain walls are more aesthetic in visual, has better connectivity between interior and exterior and also exudes a sense futuristic aura compare to normal concrete façade.
Table 5.1 Heat transfer coeeficients for different types of curtain walls (Aksamija, 2013) Material
Thermal Conductivity (W/mK)
Glass
0.8
Concrete
1.1 Table 5.2 Thermal conductivity between glass and concrete
According to both of the tables above, concrete has higher thermal conductivity than glass, double glazing and also double low-‐e glazing. This indicates that concrete is able to transfer heat to the exterior more efficiently than to glass glazing.
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Curtain glazing façade may has better weather protection and can maintain
constant temperature in the interior, however, it is not suitable for the tropical climate like in Vietnam because it becomes a barrier for the prevailing wind and the building has to utilize air conditioners in all times.
Exterior
Interior
Exterior prevailing wind is rejected by the curtain wall
Exterior
Exterior prevailing wind able to traveled into the interior space
Figure 5.1 Ventilation efficiency difference between glass glazing (left) and ventilation blocks in Binh Thanh House (right) The ventilation blocks that used in the Binh Thanh House has a series of openings which allow ventilation to occur continuously, which benefits in keeping the air in the interior to be fresh and cool. While curtain glazing facades are all sealed to ensure safety for the occupants, so it would have much less openings compare to ventilation blocks. Therefore, concrete ventilation blocks could provide better thermal comfort to the occupants compare to curtain glazing.
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Master Bedroom
Living Room & Dining Room Gym Room & Bedroom
Living Room Dining Room & Bedroom Garage (Parking Area)
Figure 5.2 Cross ventilation throughout interior spaces in Binh Thanh House Figure 5.2 shows the section of Binh Thanh House where cross ventilation occur. The ventilation blocks on the façade and alternate balconies of Binh Thanh House also induces cross ventilation to the building, which enhances air flow and air circulation within the spaces.
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6.0 Effect of the Orientation And Dimension of the Openings to the Thermal Comfort Figure 6.1 O ptimal building orientation based on annual solar radiation for very hot climate (Aksamija, 2013)
Binh Thanh House
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The figure above shows the best and worst orientation of building according to the sun path diagram. The best orientation of the building is facing the South direction where the sun exposure is the minimum. Whereas the East direction is worst orientation of the building as it is where the
Site Plan of Bin Thanh House
sun exposure is at the maximum.
The information above relates closely to the orientaion and position of Bin Thanh House as Ho Chi Minh City is at the South of Vietnam when refer to the Vietnam map. But according to the site plan of Bin Thanh House, both of the façades are facing South-‐West and East instead, which the façade facing the east would receive maximum sun exposure in the morning in case of there is no obstacles ahead.
Figure 6.2 Location of Ho Chi Minh City in Vietnam Source from http://thumbs.dreamstime.com/z/map-‐vietnam-‐8886075.jpg
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Window-‐to-‐window ratio (WWR) Ventilation blocks are one of the many examples of fenestration, other examples include windows, curtain walls, clerestories and skylights. Fenestration elements could create an impact on the overall energy consumption of the building, the occupants’ well being, health, comfort and also productivity. Poor design in fenestration such as the use of materials, dimension and construction may caused drafts, glare, noise, condensation, excessive heat lost or gain and lead to discomfort for the occupants in the building. Therefore, there is a metric that could determine the solar heat gain and energy consumption of the designed façade by showing the proportion of glazed to opaque façade area, which is the window-‐to-‐window ratio (WWR). The higher result of WWR shows greater energy consumption of the façade. Figure 6.3 Effect of WWR on energy consuption and solar heat gain for very hot climate (Aksamija, 2013)
Figure 6.2 above shows the relationship between WWR on energy consumption and solar heat gain in very hot climate, which include tropical countries such as Vietnam. The increase in WWRs causes cooling loads to increase because of the increase in solar heat gain of the building. As the facades at Binh Thanh House
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are fully covered by the ventilation blocks and some glazing, it could consider as the 80% window to wall category.
Figure 6.4 Façade of Binthanh House Source from http://afamily1.vcmedia.vn/UserUpload/27 50328/2015/04/binh%20thanh%202201504 212129067148.jpg
But as the result of in Figure 6.2 was taken from buildings of opaque façade with glazing without openings such as windows, therefore, the energy consumption for cooling in Binh Thanh House would be much lower compare to the data collected in the Figure 6.2.
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7.0 Effect of the Site Context Elements to the Thermal Comfort of Binh Thanh House
The Nghe Canal (Allows evaporative cooling that could lowers the surrounding temperature)
South-West Prevailing Wind (Summer Monsoon)
High Rise Apartment (Blocks partial afternoon sunlight, lowers sun exposure to site)
Saigon Zoo (Provide greenery and peaceful scene to the building)
North East Prevailing Wind (Winter Monsoon)
Site Plan (NTS)
The important site context around Binh Thanh house include the Nghe Canal , high rise apartment and Saigon zoo which located across the Nghe Canal. There are also 2 directions of prevailing wind blowing towards the Binh Thanh House, where both sides of the façade on Binh Thanh House are located. The South-‐West prevailing wind which travel across the Saigon Zoo and the Nghe Canal introduces evaporative cooling to Binh Thanh House, which enhances the cooling effect and temperature of the interior spaces. Moreover, the high rise appartment located at North blocks direction with the most expose of sunlight as discussed in 6.0-‐ Effect of the Orientation And Dimension of the Openings to the Thermal Comfort. Therefore, there is no worries in causing glare or visual disturbtion to the occupants in Binh Thanh House. The Saigon Zoo not only provides aesthetic nature greenery to the occupants, as the building is located in the busy and dusty Ho Chi Minh City, but also act as a air filter to the building as there are a lot of trees and plants in the zoo.
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8.0 Conclusion
Binh Thanh House is a good example of showing harmony in utilizing
traditional ventilation methods in a modern design building. Unlike buildings nowadays which extensive apply curtain walls and glazing to make transparency and connection between interior and exterior, the ventilation blocks on the façade of Binh Thanh House also serves as a barrier between interior and exterior while providing more rivacy to the interior spaces. Moreover, the materials used in the construction of Bin Thanh House include concrete for the ventilation blocks and floors, reused bamboo wave like ceiling which make the Binh Thanh House to be one of the good example of sustainable architecture nowadays.
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9.0 References Aksamija. A. (2013). Sustainable Facades. Manhattan:Wiley Fairbank. W. (Ed.). (2004). Chinese Architecture: A Pictorial History. New York: Dover Publications Inc.. Knaack. U., Klein. T., Bilow. M., Auer. T. (2007). Principles of Construction. Germany: Birkhauser. Pieri. C. (2010). Baghdad: Arts Deco Architectural Brickwork 1920-‐1950. Egypt: L’Archange Minotaure. Tettoni. L.C., Ong. E. (1999). Sarawak Style. Malaysia: Times Editions. Tusa. P. (2004). Penang, Palaysia – Penang’s Shophouse Culture. Places, 9(1), 47-‐48.
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10.0 Plagiarism Check
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