PICTURED: The Sara Cultural Center and Wood Hotel, Skellefteå, Sweden. PC: White Arkitekter. Released.
Story at a glance…
The world’s largest wooden skyscraper has been built in a small town in northern Sweden.
Complete with a cultural center and 20-storey hotel, the building is a triumph of modern wooden architecture.
Pushing the limits of sustainable design, the building captures 9,000 tons of carbon among other green methods.
If one steps out onto the 20th floor of the Sara Cultural Center and Hotel in the town of Skellefteå in northern Sweden, they can enjoy breathtaking views of nature paired with the unmistakable scent of wood.
But that scent isn’t coming from the 1.1 million acres of forest surrounding the town, it’s coming from the building itself, as the Sara Cultural Center and Hotel is currently the world’s largest “plyscraper,” meaning that all 274 feet is built with wood.
Recent evolutions in construction technology and design has given rise to real wooden skyscrapers, and like days since the World’s Fair, as nations have repeatedly tried to claim ownership of the world’s tallest building, the title of tallest plyscraper is not likely to remain for long with the Wood Hotel in Skellefteå.
But, along with being a gorgeous building it’s another landmark moment in the adoption of Scandinavian eco-friendliness.
Part of whether wooden construction is widely adopted will be based on the elephant in the room: what happens if a fire starts? Advances in fire-retardant treatments in wood are extraordinary, and a fire set in a Wood Hotel room could consume all the textiles, but still need 120 minutes before permeating the outer layer of the CLT. Meanwhile, the entire building has a sophisticated AI-sprinkler system to douse fires before they become too large.
“The design is an homage to the region’s rich timber tradition that we hope to take forward with the local timber industry,” said Oskar Norelius, Lead Architect for the building at White Arkiteter. “Together, we can create a beautiful civic center for all; a contemporary expression that ages with grace”.
The complex consists of two buildings. The Sara Cultural Center also houses the Västerbotten Regional Theater, Anna Nordlander Museum, Skellefteå Art Gallery, and the City Library, while Elite Hotels Group will run the Wood Hotel, which climbs 274 feet into the sky just below the Arctic Circle and features 205 hotel rooms, a conference hall, and sauna.
All this was accomplished thanks to a pair of new timber construction materials known as cross-laminated timber (CLT) and glue-laminated timber (GLT).
CLT involves laminating boards of wood together with glue at 90-degree angles before pressing them together under the immense pressure and steam of industrial wood presses, giving it strength and resistance in all directions; ideal for floors and wall segments.
GLT on the other hand has a higher load bearing capacity than steel or concrete relative to its weight. It’s made by layers of bonded timber running in the same direction, and is used to make the corner supports, pillars, and skeletal features of the building.
In the perfect expression of Scandinavian-ness, the 205 hotel rooms were pre-assembled and bolted in like Lego bricks (the Danes invented Lego), while the entire construction process left behind the wet work of plastering and painting in favor of raw, unstained wood, giving the whole building but the hotel rooms especially, the sense that you are in a sauna (the Scandinavians all love sauna, and the Finns may have invented the dry-wood sauna).
Some concrete was used on the 20th floor to prevent it from moving in the wind too much, and steel trusses were used in the large ceiling spaces of the cultural center and theater, but that was it.
“We had limitations in Sweden up until 1994 that limited the height of timber constructions because of the fires we had in cities and towns long ago; you couldn’t build taller than two stories,” says Norelius. “The main challenge has been getting people to accept the risk of building something that hasn’t been built before.”
The lengths which all those involved went to to cut back on the emissions is commendable for what is already one of the world’s greenest nations. The timber with which the plyscraper was made imprisoned 9,000 tons of carbon during its life. All the timber used came from local forestry plantations, and none more than 60 kilometers from the building.
Along with cutting back on delivery time and emissions for materials arriving from far away, they also came pre-assembled, meaning that far from being a noisy, polluted spike of florescent orange plastic and mud, the construction site was relatively tranquil, and emitted very little emissions of any kind from heavy machinery.
The team is proud of the eco-conscious design and engineering, and hope they can export the blueprints to other parts of the world to show it’s not a novelty of the north, but a legitimately excellent construction method.
“We are currently studying how far we could transport this building without undoing the carbon saving,” White Arkitekter’s Robert Schmitz told The Guardian. “We think it could probably go twice around the world and still be carbon neutral”.
The previously-tallest plyscraper, Mjøstårnet Tower, has had its crown taken by the Wood Hotel, but far more ambitious projects, like in Japan where Sumitomo Forestry’s W350—a timber tower stretching 1,189 feet in the air, or London’s Oakwood Timber Tower, slightly shorter at just under 1,000 feet, aim to quadruple Skellefteå’s wooden wonder of the world.
It demonstrates that the form and function of a timber tower isn’t reserved for Scandinavian sensibilities, but represents a global construction revolution.