AR1329 | Climate, Ecology, Environment
Analyse - Understand - Adapt - Tropicalize
Building Information
Location : Rue Victor Close 81 4800 Jehanster, Belgium
Year 2000
Program : Construction of a single family dwelling.
Main partners Structural engineering : Ney and Partners
Artist : Jean Glibert
Main contractors
Carcass work : Daniel Stoffels
Steel frame : Bemelmans – Balancier et Fils
Glazing and metallic frames: FMP
Roof covering : Vincent Piront Toiture Bardage
Heating - drainage: Bas
Finishing : Jamar Stephan
Specifics : glass and steel house
Awards “Highly Commended”, lors du concours international organisé par AR+D, Emerging Architecture, The Architectural Review Nomination au trophée Bénélux de la Galvanisation 2000 Euro Belgian Architectural Award 2001 Prix construction Acier 2002
Category : Individual houses
The Denis-Ortmans House was designed as a fully prefabricated dwelling that was erected on a set of foundation pillars located in the middle of a field. To optimize space within the living areas, traditional techniques were employed, such as placing the bed in an alcove and using sliding partitions, particularly to separate the master bedroom (4 sq. m) and library. The house was constructed to blend seamlessly with its natural surroundings, offering its inhabitants a strong connection to nature.
The Denis-Ortmans house is a testament on the potential of sustainable singlefamily residences based on prefabrication and sustainable design. However, the obsession with prefabrication has resulted in less-than-ideal empahsis on climatic adjustment.
What already works?
Use of Foliage
The Denis-Ortmans House has cables installed on the exterior facade, particularly on the southern and western facades. This allows grapevines and other foilage to grow and cover the facade, serving as a solar barrier during the summer months when most solar energy is deposited on the house.
Open plan
The simple spatial arrangement of the house is a glasshouse with an island containing most of the programmatic functions of the house. There are sliding doors on the eastern and western facades to allow for cross-ventilation opportunities. The space is also double-height, allowing for air to pass through unobstructed.
Steel Frame
The prefabricated steel frame on which the fenestrations and glazings are installed allows for potential addition and alterations to be easily implemented to retrofit into a tropical environment.
Material
Concrete for the interior module and flooring, which helped to regulate the temperature within the house by means of thermal inertia.
Fenestrations
The glazing assemblies are a mix of clear and partially translucent, allowing for unobstructed views, but also to reduce solar radiation (seen on the southern and western facades), and diffuse direct light.
What doesn’t work?
Roof
The roof sits square on top of the facade, with no overhang. This allows high amounts of solar radiation to penetrate into the interior spaces, as well as not protecting openings and presenting opportunities for water to leak in. The roof profile is also flat, and unsuitable for the high quantity of rainfall received in the tropical climate. The section suggests that it is also relatively thin and fares poorly against solar radiation seeping through via the roof.
Facade
The house is essentially a greenhouse, cladded in transparent and translucent glass, letting large amounts of solar radiation to penetrate into the space, and trapping heat within. This results in high thermal discomfort.
Openings and fenestrations
Sliding doors are aesthetically pleasing however functionally are quite weak against heavy precipitation. Wind-driven rain could potentially force water through gaps in the facade.
Orientation
The western facade (long side) will receive the most amount of radiation energy from the afternoon sun.
Material
Concrete, Steel structure, and glass glazings, have low u-value. This means it gains and loses radiation energy very quickly. This in respect to the temperate climate of Belgium means a rapid loss of heat energy to the environment. Artificial climate control required to regulate thermal comfort.
Ground offset
The house is raised on concrete feet, however high rainfall will require a deeper foundation and to raise the clearance of the platform and prevent the structure from sinking into the soil, and mitigate flood waters.
Additions and Alterations to improve liveability - highlighted in yellow
Point-in-time Illuminance - Liege, Belgium
Point-in-time Illuminance - Liege, Belgium
Point-in-time Illuminance - Singapore
Point-in-time Illuminance - Singapore
Tropicalize - Fenestrations
Top-hung Windows
Top hung windows, along with a horizontal shading device, allow for adequate shielding of the indoor space from rain water even with the windows open. Rainwater runoff rolls off the exterior of the building instead of going into the building.
Even when raining, top hung windows can remain open to allow for crossventilation.
Monsoon Windows
Monsoon windows allow air pass-through even while the main element is in its closed state. Comprised of a standard hinged window elements, and a secondary perforated panel that lets in ventilation when opened or closed. However, its construction (depth-wise) is quite large and given the already limited space of the house, we decided not to use this as a solution as it eats too much into the living spaces.
Key Findings
Top-hung windows have been an effective solution, providing protection while still allowing for natural ventilation. However, the small opening size makes it less effective than alternative options.
Monsoon windows have been used in vernacular architecture and is proven highly effective, buttakes too much physical space when implemented. Furthermore, its benefits are more obvious when implemented in high-rise buildings where the effects of wind-driven rain are more severe.
The Denis-Ortmans House already utilises sliding doors, which has already seen widespread implementation in vernacular architecture and tropical architecture of the region. Due to its large openings, allowing for more ventilation opportunities. The sliding mechanism is also more durable against strong winds, and would mitigate any issues regarding door swinging via wind. Futhermore, the slim profile of the sliding mechanism does not take away from the living spaces, and also preserves the box-like aesthetic of the Denis-Ortmans House.
Tropicalize - Roof
Key Findings
Sloped Roofs: Tropical roofs are typically sloped to allow for rainwater to run off quickly, as heavy rainfall is common in tropical regions.
High Ceilings: High ceilings provide ample ventilation and help to keep the indoor spaces cool. They also help to circulate air, which can help to reduce humidity levels.
Overhangs: Roof overhangs provide shade and help to prevent direct sunlight from entering the building, which can help to reduce indoor temperatures and need for artifical climate control.
Tropicalize - Louvers
We explored two types of louvers:
- Horizontal louvers of equal depth
- Horizontal louvers that form a roof overhang
While both types of louvers managed to significantly lower the lux levels, the horizontal louvers allowed us to preserve the original form of the Denis-Ortmans House. Moreover, the difference in lux levels between the two variations were too marginal to justify the additional material cost and change in the original boxy form.
Key Findings
Louvers are an extremely effective architectural feature in tropical architecture becasue of its ability to scatter direct sunlight but retain the majority of the lux levels. Additionally, mitigating rain from penetrating into the interior spaces while still allowing for ventilation pass-through.
Form Derivation
Integration of Tropical Intervention with Functional Program
Point-in-time Illuminance - Louvers Closed
Point-in-time Illuminance - Louvers Open
Radiation Map - Louvers Closed
Radiation Map - Louvers Open
Ventilation and Rainwater Management
Ventilation and Rainwater Management
Ventilation and Rainwater Management
Materials
Timber louvers
Aged Galvanised steel structural frame support
Bedroom 2 overlooking south-east direction lush tropical landscape
Dark brown aluminium window frame
Timber panel decking
Double-glazed frosted glass window
Materials
Single glazed clear glass
Aluminium stairs
Double-glazed frosted glass
Masterbedroom overlooking lush tropical landscape
Materials
Detailing
Landscaping
