Cocoon 17, Kuala Lumpur
A House in a Forest
Imagine a house that sits under the tall canopy trees of our rainforest. It does not need a roof, as the crown provides the shade. It needs no wall, as the surrounding bushes provide the privacy.
No doubt that with development there will be scaring of the earth. But there is much that we can do in minimising the scaring and there is definitely no reason for us to add salt to the injury. We can mend and improve our environment. We may even rehabilitate and rejuvenate our environment by planting trees and creating our own private garden. From this point of view sprouts the idea of re-greening the earth, of planting trees instead of concreting the earth, of letting the green run riot, of living in a verdant forest garden.
An Urban Oasis
Experimenting with the idea of greening the earth, we envision the home as a refuge that is a living, breathing green oasis that is in stark contrast to the city’s concrete and steel jungle. As a vision of a green oasis, one cannot fail to return to the images of a jungle paradise complete with rivers and waterfalls. One also would not turn away from the nostalgic images of the ‘kampong’house, surrounded by a little verdant forest of jack-fruit, rambutan and mango trees. The image is not only one of a physical endearment but an emotional attachment. It is within this paradise with children running abandonly and playing in the yard under the glorious sun that we feel safe. It is in this pictured paradise that the house is envisioned to live and breathe, playing peek-a-boo amongst the trees.
The jungle paradise is envisioned as a green cocoon wrapping itself around the house, insulating and protecting the house and the family from the external world. The jungle paradise would seem to be in another world at a different temporal plane that rightly seems to be disconnected from urbanity. It is this disconnection that insulates and provides the environment of peace, calm and tranquility.
The concept of the cocoon embodies three layers of space. The outer space is the shell that protects, and this protective layer is articulated as a forest garden that not only surrounds the building but covers it. The forest acts as a sun screen that lets in diffused light and as a visual screen that provides privacy. In reverse, the visual screen provides a delightful forest background to the house.
The second layer is the living layer where the house lies as a U shaped three storey glass and brick structure expressed in modernist terms.
Cooled and hidden under the canopy of trees the house replaces the solid walls with transparent glass that manifests the forest, turning it into a living wall. This freedom allows light and space to be made known and to express itself, with every room opening itself to the forest and the three storey central atrium gloriously transcending the house, wonderfully demonstrating the modernist idea of free flowing spaces. This transparency also allows cross ventilation through and above the house that cools the house.
The origami roof is raised above the house allowing air to breathe through thus cooling the house efficiently. The folds of the roof mimics the folds a leaf metaphorically linking the home with nature.
The third layer takes nature into the house through semi enclosed spaces and courtyard gardens, thus completing the assimilation of the house with nature.
To realise the pictured paradise, the art of landscaping is utilised to re-create the environment of a forest. With the forest first, the building is designed to assimilate itself into the forest. Here, the modernist idea of free flowing spaces and spatial transparency lend itself to interpret the building as a single coherent composition with the landscaping. Landscaping thus becomes an integral part of the building design concept no longer merely being an appendage to a building design.
In recreating the forest, plants are selected that will provide cover at three levels, the ground, eye level and canopy. Various shrubs provide a green wall along the perimeter, visually shutting out the external world. Providing cover from the sun, medium height trees with clean trunks are chosen and in the intimate scale of the house, they mimic the tall canopy trees of the forest. Trees with proper foliage are carefully planted in the direction of the sun’s movement to provide ample shading. And creepers tumble down from rooftop planters softly covering the house. As if in a symbiotic relationship with the forest, the building allows the forest to claim it by being overrun with trees and creepers. A swimming pool and garden pond then completes the forest assemblage by providing the water element.
To appreciate this forest, a ‘jungle path’ is incorporated into the forest landscape design. The path expresses the symbiotic relationship between man, his house and the forest. Accentuating that relationship further the house allows the forest to claim it by being overrun with climbers and creepers with the creepers finding a home within the house itself. Thus is the house cocooned in the green forest.
The cocoon concept shifts the emphasis away from the building to the ‘forest’. Reflecting this shift the house that rose from the wooded landscape is an austere 3 storey glass box supported with concrete and steel. Articulation and detailing of the building form is minimalist in style, keeping in touch with Mies Van Der Rohe’s dictum of less is more. Large expanses of glass breaks the building mass and the resultant ‘leftover’ solid walls are expressed as vertical planes. In the atrium side, the glasses are sandwiched between the floor slabs expressing the horizontality of the planes.
Within the forest, the building by being ‘less’ is able to express itself and empathise itself ‘more’ with nature. Here, glass is the material of choice as the transparency allows the building to hide itself within the forest and ultimately becoming part of the forest. Like a kaleidoscope, glass and water also reflect the forest of its surrounding that further immerse the building in a sea of green.
The mass of the building is reduced by introducing a deep incision into the house that cuts from the rear to the middle. This incision visually splits the house into two. Like a glade clearing in a forest, the incision sports a body of water in the guise of a swimming pool that invites the forest deep into the house. The living areas opens to the swimming pool and gardens allowing the occupants to experience the forest and virtually touching it. Bubbling pool water and falling rain adds an aural dimension to the light and air of the forest experience.
The house looks internally to a swimming pool where the extensive use of glass breaks down the visual barrier between the internal and external spaces. On the inverse, the central atrium that is transparent heightens the visual connectivity between the internal spaces. Together, there is a coherent visual flow within the house itself that then flows to the external spaces furthering the concept of spatial transparency.
The U shaped topology of the building naturally opens up the house, allowing for the maximum penetration of light into the deepest recesses. The light animates and enlivens the spaces. However the light needs to be soothed and thus balancing this nakedness, the house is veiled behind a shroud of green. This veil of green that filters the sun’s rays imbues it with an ephemeral quality. Light itself is no longer static or one dimensional when it becomes animated as the trees sway and the leaves flutter with the wind.
All the rooms including the living room, as well as the dining and kitchen, are adorned with floor to ceiling windows, allowing light to penetrate deep into the rooms as well as creating a seamless interplay between the interior and exterior spaces. The living room and the dining room with their sliding doors opened are effectively transformed into garden terraces. These ‘indoor terraces’ with their accompanying spill over spaces enhances the physical connectivity between internal and external spaces. At the upper levels, the bedroom balconies perform the same connecting functions.
The master bathroom and jacuzzi are articulated as semi-enclosed spaces. Instead of walls, louvres and plants provide visual barriers where the later enhances the garden ambiance. This ambiance brings in the garden and the forest right into the bedroom as the spaces connect with each other.
Without light comes claustrophobia and with it the slow strangling of a space. Light reveals and animates what is hidden, whereby shadows accentuates the form. When a space is revealed it is the quality of light that influences the emotion of that space. Thus light must be controlled especially in this climate where the sun is harsh.
Technology and Art
Architecture sits at the intersection of technology and arts creating a symbiotic relationship that pushes the boundaries of architecture. Advances in glass technology has allowed the use of Low-e glass that is used throughout the house. Low-e glass works by either inhibiting the emission of radiation or increasing the reflectance thus reducing heat transmittance through it. With less mass and higher reflectance than masonry, glass dissipates heat and cools relatively quick thus maintaining a comfortable ambient internal temperature.
With the use of glass spatial transparency is maintained within the house. Continuing with the concept, the structural level and grids are determined by the structural qualities of the glass. The glasses are seamless to maintain the visual clarity.
Bridges at the first and second floors span the atrium and connect the two wings of the house without intermediate columns. The articulation reduces clutter in the atrium and enhances the spatial transparency. In an experiment with its structural properties, the bridges are constructed from a single sheet of glass. The choice of a glass bridge was made in order to maintain the transparency of the atrium space that would otherwise have been jeopardised.
A steel spiral staircase is hung at one end of the glass bridge. The steel spiral staircase is designed as a self supporting freestanding structure suspended from the second floor landing. Like the structure of a DNA, the helical structure of the stairs provides the necessary structural integrity that is expressed in a sculptural form.
Technology has allowed the usage of very large doors that stretch from the ground to the ceiling and as wide as the corridors. When the doors are open it is like part of the wall has given way. Now without a wall, there is visual clarity between the spaces and the spaces are allowed to connect creating a large unimpeded volume of space. This technical solution augments the play of visual clarity in expressing the concept of spatial transparency.
Passive Cooling Design
In a hot humid tropical environment the design concept refer to these basic principles;
i) to reduce or halt heat transfer into a building
ii) to remove unwanted heat from a building
ii) to create a cooler micro-climate
iv) usage of low thermal mass materials
In an urban context the buildings are usually insulated from the external environment due to the higher urban heat island condition. In due course the method to maintain a stable comfort level within a building have usually surrendered to active methods namely air-conditioning. But relying on active methods do not concur with the vision of a cool green paradise that the house lives in. Memories of siting under a cool shady tree has brought forward the proposition of utilising the forest garden as an element to create a comfortable environment, passively.
Passive cooling refers to technologies or design features used to cool buildings or to maintain a lower ambient temperature than external temperature without power consumption or mechanical means. The cooling strategy intergrates the understanding of heat transfer and air movement within the building envelope and spaces articulation.
The source of heat in a tropical climate is mainly from the sun with secondary source from the ambient temperature and re-radiated heat. The main strategy is therefore to stop the sun’s rays from reaching the building by shading it with roofs, deep overhangs, awnings or louvres.
With the concept of the cocoon, it is the trees of the forest garden that provide the main shading cover with other elements of the building complementing it.
The folded roof of the house is raised above the roof slab effectively creating a heat shield. The large airspace below the folded roof allows it to be ventilated without fuss thereby cooling the space and stopping heat from reaching the house. The raised roof also allow space for planters whose creepers tumble down the side of the house absorbing the sun’s rays that might otherwise have heated up the walls.
Secondary source of heat from ambient temperature and re-radiated heat are also absorbed and filtered out by the forest garden.
The second strategy is to induce natural cross ventilation within the house to remove internally generated heat. The house has a central atrium with a skylight plenum that encourages internal air movement to ventilate the house through the roof. The internal rooms from the ground floor all the way up to the third floor open directly to the atrium for an unimpeded and direct flow of space. Hence there is no restriction to the flow of circulating air across and through the house that results in an efficient cross through ventilation.
In a rural context the cross ventilation that removes the internal heat would bring in relatively cooler air from the outside where the external ambient temperature would be lower due to evaporation and transpiration of the vegetation. In an urban context however, there would be higher external ambient temperature due to less vegetation and heat re-radiated from urban structures. Instead of relatively cooler air, it would be relatively warmer air that would find its way inside.
In the middle-east there are wind-catchers that bring in forced air from the outside to ventilate the houses. The wind-catchers solved the problem of hot air by having large earthernware jars filled with water or other similar devices to cool the incoming air by evaporation.
From this lesson evolves into the third strategy. The external air is cooled by the forest garden through evaporation and transpiration whereby the forest garden literally absorbs the heat. This creates a micro-climate that is relatively cooler and whose air is then circulated within the house. With the cooler micro-climate, there is a tendency to fully rely on natural ventilation.
The fourth strategy is to utilise low thermal mass building materials. The purpose of high thermal mass building materials are for the materials to absorb heat during the hotter day and release the heat slowly during the cooler night-time. This strategy works well for climates with a large temperature difference between night and day where you would need night-time heating. It doefinitely does not work here where the difference between night and day temperature is low. Therefore the idea is to uitlise low mass materials that would retain less heat and would lose it relatively quicker.
Glass as a low thermal mass material is used quite liberally in the building, and where not used, the building is covered by plastered brickwalls. To offset for the higher thermal mass, the brickwalls are painted white to reflect and therefore reduce heat absorbance. Glass may be anathema to tropical architecture as traditional glass allows heat to flow through. But technology has found a way for glass to reconcile itself with tropical architecture in the shape of Low-e glass that is used throughout the house. Low-e glass works by either inhibiting the emission of radiation or increasing the reflectance thus reducing heat transmittance through it. With less mass and higher reflectance than masonry, glass dissipates heat and cools relatively quick within the cooler micro-climate thus maintaining a comfortable ambient internal temperature.
The house has experimented with the interpretive utilisation of nature as a living architectural element acting as the roof and the walls of the house. The roof and walls are no longer static but alive and growing, ever changing, giving different persona to the house as it ages. Meanwhile, light and breeze animated by the foliage exude different emotion at different times of the day.
With this approach there is a symbiotic relationship between the forest and building. Here the building and landscape design are handled as one composition that transcends the traditional building design approach with the landscaping as an appendage. Within the forest cover, the house is able to extensively utilise glass that turns the house transparent, bright and airy, reconciliating nature with modern architecture.
The idea of spatial transparency has been articulated through both the free flow of physical space and visual clarity. The third aspect of the idea is by bringing in the forest into the house, it gives the impression that walls do not exist and that therefore the house is no longer constrained.
The result is a modern house that works in concert with its environment in respond to the tropical context. The utilisation of trees and green as a living architectural element not only performs wonderfully as a cocoon but enhances the living environment and improves the quality of life of its residents. The interpretation is a working solution that sets the precedent for the development of other residential types.