Interplay of Lines

It appears that WOHA, the firm of Wong Mun Summ and Richard Hassell, is not alone in designing attractive high-rise-towers in Singapore that are full of vegetation — often on several levels and also across their facades. The new CapitaSpring tower in the city-state’s financial district was designed by Copenhagen’s BIG with Carlo Ratti from Turin, Italy — neither member part of Singapore’s pioneering endeavor to breed a new type of office tower that is literally and metaphorically “green” inside and out. Yet, does it make sense to plant trees inside towers at absurd heights? The answer given by the biophilic CapitaSpring skyscraper is an emphatic “YES!”

Traditionally Singapore’s CBD has been dominated by Western-style, fully enclosed and air-conditioned towers (regardless, quite a few were designed by such Japanese architects as Kenzo Tange and Kisho Kurokawa). The CapitaSpring tower is the latest iteration of a new type of tower that is porous, incorporating sky gardens and a rooftop garden.

At first glance the tower looks like a typical Late Modernist “pin-stripe suit,” but the vertical lamellas covering the 51-story-tower are pulled apart to reveal patches of green, in some cases bursting through the facade and looking like a cartoon inmate bending the bars of his prison cell. The design of the tower wants to “blend the contemporary and the tropical” and create a “garden in the city,” according to Brian Yang, BIG’s partner in charge of the project.

Earlier this century Singapore introduced a “Green Plot Ratio” (GnPR) requirement for all new downtown buildings of at least 1:1, aligned with Le Corbusier’s century-old dream that a city’s green roofs could give back the land the buildings take up. At CapitaSpring the landscaped area totals 8,300 m2, resulting in a ratio of 1:1.4 — surpassing Le Corbusier’s dream at 140% the size of its site. The design shows that “city and countryside, culture and nature can coexist, and urban landscapes can expand unrestricted into the vertical dimension,” as put boldly by Bjarke Ingels. If only it were that simple!

Few cities in the world are blessed with the lush vegetation of Singapore. Elsewhere, vegetation in and on buildings comes with a lot of maintenance. Plus, the weight that water and soil adds to the tops of towers can come with economic and ecological price tags. The structures — often made of concrete, as in the Bosco Verticale in Milan — need to be more rigid and altogether bigger, and distances traveled by elevators increase, requiring more power and service space. 

These days we dream of mixed uses and the “city of short distances.” CapitaSpring fulfills that goal…somewhat: The first eight floors are serviced residences and the top 29 floors are offices, with public spaces at the top and at the “hip.” The landscape design is somewhat coarse, but the scale of this garden in the middle of a skyscraper is unlike any other in the world.

The architects call their new type of commercial tower “vertical tropical urbanism.” Downstairs, just above street level, the Hawker Center that used to be located on the site found a new home and attracts young, well dressed office employees from the nearby towers to have a tasty, cheap Chinese meal from one of the 56 food stalls, served on a plastic plate for around 5 dollars. Upstairs, there are 80,000 plants, glimpses of which can be had through the facades. At the “hip,” a big lush garden sits between the offices above and the residential portion below. Meandering garden paths circumnavigate the central core several times, providing a shelter from sun and rain that are equally abundant in Singapore’s weather.

During lunchtime, only tenants can roam the 35-meter-tall open-air gardens, but in the morning and afternoon two public elevators will shoot anyone up to the sky gardens, where a spiraling promenade weaves architecture with tropical vegetation. The public spaces across the building “leverage technology and integration with natural elements,” says Carlo Ratti. The rooftop garden is home to a tiny urban farm that grows 150 species of fruits, vegetables, and herbs to supply the in-house restaurants with fresh greens.

The tower, carried out with RSP Architects Planners & Engineers as local architect, has been awarded a Green Mark Platinum certification by the Building and Construction Authority (BCA) of Singapore. The BCA also set up the Green Plan 2030 that specifies Landscape Replacement Areas, or LRAs: Developments shall provide an LRA that is minimally equivalent to the site area or bigger. This ratio is determined in the so-called GnPR. While these parameters seem somewhat over-regulated, like everything else in Singapore, they help strengthen the city-state’s position as an ambitious green-building pioneer.