Architecture: Singapore’s shapely butterfly house

On the affluent, palm-lined street of White House Park in District 10 – one of Singapore’s most desirable residential areas, a stone’s throw from the designer stores on Orchard Road – sit ambassadorial mansions and some of the city’s distinctive black and white “bungalows”, the large colonial houses built by Tudor-loving Brits in the late 19th century.

And then you come to number 11, a gleaming, geometrical puzzle of a house that resembles a futuristic butterfly perched on a tower of lily pads. The insect’s body is the house’s spiralling, light-filled spine and its wings are the five crystalline pods that fan out over large terraces. Or, as the owner prefers to see it (he is chief executive of a large Singapore-based bank), “a spaceship that has landed in the neighbourhood, but with rectilinear rooms”.

Singapore’s skyline is rapidly changing with new landmark developments including the $8bn Marina Bay Sands, a vast new leisure resort, which includes the world’s most expensive standalone casino. While land is scarce, they are making more of it in Singapore, with huge land reclamation works facilitating projects such as Gardens by the Bay, a 101-hectare city centre site that enhances Singapore’s reputation as a “garden city” with three expanses of waterfront greenery.

But it’s not just a destination for commercial innovation. Modern residential projects, such as 11 White House Park, are increasingly replacing dated homes built in what architects call Singapore’s “neotropical vernacular” – houses with steep pitched roofs, large overhangs and verandas that cater equally to monsoon rain and intense sun.

When the architect Peng Beng Khoo was commissioned to build this new spaceship-like residence – a two-year project completed in late 2012 – he says he was immediately fascinated by the contradiction the brief presented. “The husband loved more definite geometries and organisation, while his wife was attracted to free and fluid lines and curves,” says Khoo, co-founder, with his wife Belinda Huang of ARC Studio, whose high-profile works include the award-winning Pinnacle@Duxton. “We embarked on creating a house that was architecturally expressive and yet had clean and regular rooms.” Its seven 50-storey blocks containing 1,848 flats can claim two world records: for the tallest public housing and the longest sky gardens – “flying green”, as ARC calls them – each 500 metres long and hovering on the 26th and 50th floors.

With his private house commissions, Khoo is similarly groundbreaking. Stare for long enough at 11 White House Park and you may spot that it has no grid lines – the structural blueprint that typically defines the design of a building.

Khoo describes the house’s “two geometries” – the triangulated crystal-like pods, the living areas for sleeping, eating, relaxing, etc, and the curvaceous expanses, such as the sweeping staircase and other “circulation spaces” – as blending together seamlessly.

“One important idea we were expressing was that of unity,” he says. “It’s about two coming together to become one – to express through architecture how our clients, as a couple, are united even though as individuals they are so different.” To achieve this, another seamless partnership was required – between architect and engineer.

Khoo likes his designs to emerge organically, rather than starting a project with a fixed form in mind. So he teamed up with Dr Hossein Rezai of the London-based structural engineering consultancy Web Structures.

Rezai – who has a philosophy of “whatever the engineering textbook says don’t do, we do” – is the man Norman Foster and Richard Rogers sometimes turn to when they have a project with a sticky engineering problem.

It’s about two coming together to become one – to express through architecture how our clients, as a couple, are united even though as individuals they are so different

With the Singapore project – a 12,000 sq ft property, for which the construction costs for a building of this specification would typically be about $480 per sq ft (making it a $5.8m build) – the aim, says Khoo, was to turn a series of unusual shapes into “a house that was ingenious, buildable and cost-effective. We saw how the two different geometries and architectural forms came together in a cohesive whole – just like how a couple would move together as they danced.” Rezai, who specialises in designing tall buildings in earthquake zones and extreme climate conditions, sees his role as melding two conflicting ends of the building spectrum – “design sensitivity and cost efficiency”. And he calls this process of finding the happy medium “fusion engineering”.

“There is a traditional belief that more design means more cost, and less money means less design,” he says. “We are showing, through a track record of real projects, that this doesn’t have to be the case. With 11 White House Park, the free and organic form of the architecture doesn’t lend itself to the ordinary orthogonal grids usually used in the industry to define the various spaces. We set out to develop a structure that is defined with its nodes in three dimensions.”

The building’s unusual form demanded painstaking attention to detail. Every piece of granite, tile and glass needed a template before it could be cut. Every piece of aluminium cladding was custom-made and the curvilinear staircase laser-cut from thick pieces of steel, welded together and hand-polished.

“Every component of the house was customised, down to the door handles,” says Khoo. “Landed houses”, such as this, are rare in Singapore, accounting for just five per cent of the housing stock, with the bulk dominated by affordable Housing Development Board apartments.

As land is scarce, the few houses that do exist typically come on relatively small plots that afford little privacy – so the city’s high-end, contemporary homes are often designed as inward-looking open-plan spaces with sliding glass panels that open up to gardens or courtyards with pools.

“Because of the climate, Singapore architecture is all about the transition from inside to outside,” says Soo K Chan, the founding director of SCDA Architects, whose Singaporean projects range from one-off modern villas for private clients to “culturally sustainable” housing projects, such as the Sky Terrace @ Dawson, where the tower blocks are linked by floating gardens.

“The traditional Singaporean architectural style is a bit of traditional British, such as classic Palladian, with a bit of Chinese influence,” says Chan. “But once Singapore became independent, resources were so poor that it was dependent on importing services and ideas and encouraging foreign talent to come in. And that’s still the case.

“For architects, it’s a very contemporary, international and progressive place to work. Many, like me, study or work overseas, then return to adapt the foreign influences they have acquired to the Asian culture, climate and how people live.”

With limited space come high land prices. In the “leafy suburbia” of District 10’s Tanglin neighbourhood, Knight Frank is marketing a newly-built two-storey, four-bedroom house that – as is the fashion for such properties – appears to float, with the pool’s edge running right up to the property. It’s on sale for $36m.

“It’s not unusual for small plots of land alone to cost $16m-$24m,” says Soo K Chan. “But it means that, as the design and construction cost a fraction of that, clients are happy to allocate a large budget to building homes that are custom-built to match their aspirations. The norm is homes on plots of around 10,000 sq ft, with build costs of around $480 per sq ft.”

The ingenuity of fusion engineering means couples with conflicting architectural tastes, such as the owners of 11 White House Park, can still build their ideal home together. And such projects are becoming more common.

“Singapore is fast-becoming a choice destination for wealthy individuals to build evermore expensive homes as an opportunity to express themselves,” says Peng Beng Khoo.

“For well-heeled homeowners here, the act of creating their own home is the highest form of luxury.”