The largest wooden building in Asia is in Singapore

Singapore (CNN) — Singapore has long been considered a “garden city,” a term coined in the 1960s by Lee Kuan Yew, the country’s founding father and former prime minister. Since then, the island has embarked on extensive tree-planting programs and has embraced so-called “biophilic” architecture, in which vegetation is often seen creeping up urban facades or spilling out of skyscrapers.

A new six-story university campus is the latest ode to nature in Singapore. Home to the business school of Nanyang Technological University (NTU), the gently curving design features sunlit atriums, open-air study areas with lush backdrops, and elevators descending into beds of tropical plants. Everything from banisters to pews to door frames and room dividers (and even an adjoining bus shelter) was built from wood.

Also structural beams and columns. In fact, the building is constructed almost entirely of solid wood, a new generation of engineered wood, layered and bonded with strong adhesives, which is pushing the boundaries of architecture. At 43,500 square meters, it is the largest wooden building in Asia by floor area.

Named Gaia, after the ancient Greek goddess of the Earth, the project opened in May and cost S$125 million (US$93 million) to build. Its exposed wood structure has no siding or paint, a design decision that celebrates natural materials and gives visitors the feeling of walking among trees.

According to the famous Japanese architect responsible for the project, Toyo Ito, that was precisely the objective. “In my designs I always try to create a connection to nature, like the trees and the water,” he told CNN shortly after the building’s groundbreaking ceremony. “The fact that they mention that it feels like walking into a forest shows that my vision has been fulfilled.”

Laureate of the Pritzker Prize (often referred to as the “Nobel” for architecture) in 2013, Ito designed Gaia together with Singaporean design firm RSP. It has an auditorium for 190 people and a dozen classrooms, as well as research facilities, offices for teachers and large study terraces.

Apart from the toilets, the ground floor slabs and the exterior stairs, which were all made of concrete (partly due to local regulations), the structure was made from felled spruce wood from Austria, Sweden and Finland. The timber was prefabricated into heavy-duty panels and beams in Europe before being shipped to Singapore.

Global trend

In recent years, the number of large wooden structures built around the world has increased enormously. Some countries even allow skyscrapers, such as the 25-story, 86-meter-tall Ascent in Milwaukee, Wisconsin, which is the tallest wooden structure in the world.

Asian cities have been slower to adopt this trend than European and North American ones. Singapore’s building regulations only allowed wooden architecture to rise up to 24 meters at the time Gaia was approved, although this height restriction has since been lifted. But Ito, 81, believes attitudes are “changing rapidly” in Asia: “Singapore is especially quick to make these things happen.”

The Building and Construction Authority of Singapore (BCA) claims that the use of mass timber can reduce dust and noise on construction sites, while speeding up projects by up to 35%. Counterintuitively, proponents of wood buildings claim that they may also be safer and less prone to catastrophic collapse than steel frame buildings in the event of a fire (although not all experts agree).

Proponents of solid or engineered wood point to the relatively slow and predictable rate at which the material burns. Gaia’s designers also added a “sacrificial layer” of wood to the building’s beams that, in the event of a fire, would char and protect the wood below.

Many of the supposed advantages of solid wood are, however, environmental.

About 40% of global energy consumption is attributed to the construction and operation of buildings. But unlike concrete and steel, the energy-intensive production of which is responsible for a significant part of the environmental footprint of buildings, trees absorb carbon dioxide throughout their lives.

If a tree is turned into solid wood, this embodied carbon is sequestered, rather than returned to the atmosphere. Studies suggest that one cubic meter of wood can store approximately one ton of carbon dioxide.

Wood also works as a natural insulator which, in hot places like Singapore, traps less heat than concrete (or reduces heat loss in cooler climates). And while Gaia’s designers say they didn’t calculate the emissions saved during the construction process, they say that, in operation, the structure produces 2,500 metric tons less carbon dioxide than its concrete or steel equivalents, an annual savings equivalent to removing more than 550 vehicles on the roads.

passive cooling

Energy savings are not limited to materials. On the one hand, the exterior of the building has strategically placed structures that cast shade on the façade, helping to keep it cool.

Bursts of artificial air conditioning are also conspicuous by their absence.

Instead of mechanical fans, a feat in a country located less than 140 kilometers north of the equator, Gaia’s air conditioning system relies on “passive cooling”, which pushes cold water through coils to cool the air. surrounding. The windy north-south orientation of the building favors natural ventilation by aligning itself with the direction of the prevailing winds in Singapore.

The country’s authorities designated Gaia as a “zero energy” building that (with the help of solar panels on the roof) produces as much energy as it consumes. To date, only 16 buildings in Singapore have achieved this distinction, and precisely half of them are owned by NTU, including a campus sports hall, also designed by Ito.

At the inauguration of the building, the president of the university, Ho Teck Hua, used his speech to boast of having the “greenest campus in Singapore”.

It remains to be seen what the students at the business school in his new home have to say: classes don’t start here until the new academic year, in August. But there are more and more evidence that the use of wood in architecture can have a positive effect on the well-being of the occupants, including the reduction of stress levels.

Ito, whose grandfather was a logger, says his design philosophy is still based on the comfort of the users of his buildings.

“I always keep comfort in mind,” he explains. “If a building is comfortable, people will stay in it and visit it every day. I want to create architecture that makes people want to live.”

— CNN’s Mayumi Maruyama contributed to this report.