Flower power: Singapore's Gardens by the Bay by Wilkinson Eyre
Wilkinson Eyre’s conservatories at Singapore’s Gardens by the Bay are a popular, aesthetic and technical success, writes Ruth Slavid
When this year’s World Architecture Festival’s super-jury awarded the supreme accolade of Building of the Year 2012 to the cooled conservatories at Gardens by the Bay, they were not swayed by the political appositeness of awarding the gong to a project in the host city of Singapore.
But they may well have been influenced by the fact that they had actually seen the project, at least from the nearby Marina Bay Sands Hotel (AJ 01.11.12), where they were staying.
The conservatories are stunning - both from afar and inside. Unlike so many buildings which seem smaller in reality than in photographs, the two great cooled glasshouses loom large on the approach road from the airport. The gardens within which they are set are a work of great imagination. The result is a popular, aesthetic and technical success. It is also distinctly odd, when seen from a western European sensibility.
The generous gesture of devoting so much prime space to public amenity is, for a start, hard to grasp. Partly it is down to Singapore’s stated intention to be a ‘city in a garden’ - and a walkable one. Despite its rising population, its proportion of green space has increased from 35.7 per cent to 46.6 per cent in recent decades.
The Marina Bay area where the gardens and their distinctive pair of conservatories are located is on land reclaimed from the sea in the 1970s in anticipation that the city-state’s business area would need to expand.
‘We wanted a prime waterfront address,’ explains Mah Bow Tan, the politician behind the project. Gardens by the Bay is both a responsible gesture and a means of adding value.
The technical demands of glasshouses - which in this case need to be cooled, rather than heated - was a challenge that Wilkinson Eyre and building services engineer Atelier Ten had tackled together on a much smaller scale in the alpine house at Kew Gardens. The solution used there - a labyrinth - was not suited to Singapore’s climate, but the recognition of the need to let in as much light as possible, while minimising heat gain, was important.
But the other difficulty for a European relates to the visual aspects. Grant Associates’ masterplan for the 54ha garden is based on the shape of an orchid, Singapore’s national flower. This is not obvious to the visitor but the thought that has gone in to creating a variety of beautiful and instructive spaces, including a new lake, is plain to see.
The lush tropical planting is a bonus, though in Singapore such luxuriance is the norm. For Singaporeans, the Flower Dome’s Mediterranean plants feel far more exotic. Even the rather kitsch harvest festival-themed displays of early October were a huge hit, with piles of pumpkins and straw chickens proving a magnet for photographers.
Externally the desire to add zing is evident in a plethora of metal archways in green and purple, the colours of the indigenous mangosteen fruit. This seems unnecessary to western eyes, but what cannot be denied is the visual drama of the ‘supertrees’, Andrew Grant’s invention to provide a visual contrast with the glasshouses by day and night. In another of Singapore’s reverses, strolling in gardens is more popular by night, when the temperatures are more tolerable. The gardens are open from 5am until 2am.
The tallest supertree, at 50m, contains a bar and viewing platform. The central ‘forest’ supports a high-level walkway and PVs on top of the tree structures power their lighting. Other trees accommodate a discharge from the desiccant system and a flue for the boiler, in keeping with the underlying concept that technology should play second fiddle to the visual appeal and the plants.
For the trunks of the trees, structural engineer Atelier One has combined concrete and steel to create anticlastic surfaces which leave one thinking not about the engineering but about the strange beauty of the structures.
The conservatories - one dedicated to a dry Mediterranean climate and the other to a cool, moist cloud forest - define the edge of the gardens, overlooking the bay. Development of Marina Bay will mean more tall buildings, and this area will be least impacted by overshadowing. Sunlight is essential for the plants to flourish. Studies by client NParks determined that a peak light level of 45,000 lux was crucial. Although Singapore is much hotter than the Mediterranean, it is also far less sunny, so light is at a premium. The profile of the ribs which form the domes was refined to ensure this. Retractable shading is available for the sunniest days.
It was clear early on that two separate glasshouses were required because of their very different climatic requirements. Where the flower dome is wide and expansive, the cloud forest dome is taller and more pinched. ‘We decided that, if we were showing plants from the high-altitude tropics, we needed a hill,’ says Wilkinson Eyre director Paul Baker.
Visitors pass a vigorous waterfall before taking a lift to the top to walk along a steamy, vertiginous walkway through the cloud forest, in which many epiphytic plants grow directly out of nutrient-rich render on the walls. One of many clever touches is that this ‘mountain’ doubles as the exterior of a building containing a black-box display about climate change.
While both domes are pleasingly cool, this is a side-effect, since they have been designed for the comfort of plants, rather than people. Given Singapore’s climate, powered cooling is essential both during the day and by night. Excess moisture is removed from the air by desiccants rather than refrigerant techniques, a far more energy-effective solution. The air in the domes stratifies, so it is hottest at the top (where the more tolerant baobabs are in the flower dome).
The real bonus came when NParks and Atelier Ten realised that the entire cooling cycle could be powered using biomass from tree trimmings and old pallets - waste that would otherwise have been driven further to landfill. Patrick Bellew of Atelier Ten describes the project as ‘a beacon for applied sustainable design in the region’. It is a reasonable claim.