Energy bill RM400 per month, compared to RM3,000 for a house of similar size
House has a roof U value of 0.14 and a building envelope OTTV of 29.63
Night view of the S11, which won two awards at the 2011 Asia Pacific Design Centre Awards in Wuxi, China (photo credit: Lin Ho)
It may be Malaysia’s first Green Building Index (GBI) Platinum-rated residential house, but the S11 is really a delightful residence in many different ways.
Owned and designed by architect Dr Tan Loke Mun of ArchiCentre Sdn Bhd, the award-winning home comprises a wide range of green elements in its design and construction.
Tan, who was the team leader that led the development of the GBI rating system by the Malaysian Institute of Architects, better known by its Malay name Pertubuhan Akitek Malaysia (PAM), and the Association of Consulting Engineers (ACEM), is a strong advocate and driver of the green building movement in Malaysia.
Daylight sundancers facilitates natural illumination (photo credit: Lin Ho)
“The old house on the site was built in the early 1960s and had become dilapidated over the years. When I bought it, I designed a new green tropical house for the site and conceptualised it along the lines of a tree,” says Tan.
The three-storey bungalow was a gold award winner in the detached/semi-detached and green home categories in the haven/The Edge My Dream Home Awards 2011. At the 2011 Asia Pacific Design Centre Awards held in Wuxi, China, in December, it beat more than 500 international projects worldwide to win two awards, the Sustainable Design Award and the Residential Unit Award.
Located in the established suburb of Petaling Jaya, the S11 has a built-up area of 12,000 sq ft and features a design akin to a tree in the hot tropics with a large insulated canopy roof constructed of lightweight recyclable profiled steel metal sheets coated in a light off-white colour to minimise heat absorption.
Extensive canopy provides additional shade (photo credit: Lin Ho)
Tan says much of the demolished house materials were re-used. Old crushed concrete roof tiles were used for gravel fill, while old clay bricks were cleaned and re-used for feature walls. The roofing timbers were used for formwork strutting and propping, while crushed concrete and cement aprons were re-used for backfilling aggregate.
The S11, which has 5+1 bedrooms and six bathrooms, has a north-south orientation for all its openings and windows. The double-volume family room is located on the first floor and the 7-m-high full sliding glass walls facilitate maximum cross ventilation whilst also opening up the entire internal living space unto the outdoor deck.
Most of the internal partition walls were removed to promote cross-ventilation and to create unobstructed space between the living room and the koi pond, as well as the dining area, which opens out into a lawn leading to a 6.5 m x 17 m saltwater pool. The latter and the koi pond help provide evaporative cooling for the house.
The 12-seater dining table is made from recycled timber. The 45-cm-high daylight panel along the floor lets in light but not the heat (photo credit: Lin Ho)
The east and west walls are constructed of insulated light weight blocks, and have minimal windows. These walls are also coated with heat-reflective paint in camouflage motif as well as shaded by a wire netting screen wall of fruit and vegetable climbers.
Heat gain is also reduced via a roof insulation that consists of 200-mm-thick 50 kg/cu m rockwool and two layers of heat-reflective foil. To further improve heat insulation, a 200-mm-thick ventilated air space is left between the metal ceiling lining and the rockwool. This resulted in an overall roof U value of 0.14 while the building envelope overall thermal transfer value or OTTV is 29.63. (The U value represents the thermal transmittance of a structure, and the lower the value the better. The OTTV is a measure of the average heat gain into a building through its envelope.)
To ensure all living spaces have adequate natural daylighting, low-E laminated glass is used for all windows and glass door panels. In addition, throughout the house, glazed light pyramids in pipe tubes filter sunlight through the light boxes on the roof, channeling it to the interior space to minimise the need for artificial lighting.
The S11 house is ventilated by steel framed glazed pyramids, combined with specially designed wind turbines (photo credit: Lin Ho)
The steel framed glazed pyramids, combined with 15 specially designed wind turbines, provide the house with “stack effect” ventilation. Tan says: “These turbines are driven both by wind as well as convection when the air within the glass pyramids heat up as a result of the greenhouse effect. A three-degree differential is enough to spin the turbines by convection. As a result, we hardly need to use the air-conditioner.”
A 5 kWp photovoltaic installation and solar water heaters are mounted on the canopy roof. “Currently, the solar panels generate an average of 15 kW per day. As the house was recently registered under the feed-in tariff (FiT) scheme, I believe the panels should generate a positive cash return of a few hundred ringgit per month,” says Tan.
Energy savings from the insulated roof and other features also contribute to savings of a few thousand ringgit every month, based on a hypothetical comparison to the energy use of a house of similar size. “My current electricity bill is only about RM400 (US$130) per month, whereas a normal house of this size would probably average around RM3,000 per month.”
Another function of the canopy roof is to collect rainwater and direct it into rainwater harvesting tanks. Filtered of sediment, the water is then used to flush the toilets, wash cars and to water plants. The bathrooms are fully equipped with water-efficient fittings, while the urinals are fitted with a waterless system. “By keeping water usage to a minimum, my water bills have been zero each month ever since we occupied the house,” he says.
The timber decking on the ground floor is made from old cengal wood collected from timber yards over the years, while the timber flooring and upper decks were sourced from sustainably managed forests (Forest Stewardship Council certified). Even the 12-seater dining table and several other pieces of furniture are made from recycled timber.
Lighting for the house comprises energy-saving T5 tubes, LEDs and compact fluorescents. Low-VOC paints, adhesives, sealants and varnishes were used throughout the house. A composting yard treats all household organic and garden wastes, and provides high-grade compost fertiliser for the vegetable and fruit gardens. Tan says: “Because we live in a green house, we have learnt to live quite sustainably with minimal wastage.”
Dr Tan Loke Mun & Chew May-Ann
Dr Tan Loke Mun of ArchiCentre Sdn Bhd
Greenscapes Sdn Bhd
ArchiCentre Sdn Bhd
C & S engineers:
Jurutera Perunding TSSC Lim Sdn Bhd
Dr Tan Loke Mun of ArchiCentre Sdn Bhd
Atlantic Builders Sdn Bhd
GBI Platinum (DA)
Gold Award, haven/The Edge My Dream Home Awards 2011
Sustainable Design Award and Residential Unit Award, 2011 Asia Pacific Design Centre Awards