18/01/2025
TIMECO₂ FUTURES
Sweden is Building the World’s Largest City Made Entirely From Timber
8 MINUTE READ
Sweden is moving away from emissions-heavy steel and concrete to renewable mass timber.
Sweden is moving away from emissions-heavy steel and concrete to renewable mass timber. Erika Gerdemark/Bloomberg—Getty Images
BY MADDY SAVAGE
JANUARY 18, 2025 8:00 AM EST
A yellow crane hovers above a building site in Sickla, a former industrial neighbourhood that’s home to one of Stockholm’s biggest real estate projects. But instead of delivering concrete, it’s manoeuvring giant chunks of wood to construction staff working in sub-zero winter temperatures.
This is the beginning of what Swedish property developer Atrium Ljungberg describes as “the largest mass timber project in the world.” On the outskirts of Sweden’s capital, construction of ‘Stockholm Wood City’ began in October, several months ahead of schedule, and is set to provide 2,000 new homes by 2027.
The company’s core goal is to improve the sustainability of construction projects. Building with wood instead of concrete and steel in 80% of new buildings would, according to a 2020 study by Aalto University and the Finnish Environment Institute, help offset half of Europe’s construction industry emissions. Atrium Ljungberg is also championing the idea that spending time in buildings made with natural materials can help improve our wellbeing. “We can tell the story about how to build a liveable city, how to add nature into the city and build something sustainable,” says Håkan Hyllengren, business development director for the project. “It's not just about wood, it’s the whole concept.”
Large-scale wooden building projects are growing in popularity globally. Two years ago, Singapore opened a 468,000 square-foot wooden college campus building. Seattle opened a landmark eight-storey affordable housing block, also in 2023. And in Sydney, a giant timber retail and office space is currently under construction.
But Scandinavia—with both a long tradition of building wooden villas and cabins, and prioritising environmental issues—is perhaps unsurprisingly, ahead of the curve when it comes to ramping up construction of multi-storey mass-timber properties. Norway’s third-highest building, Mjøstårnet, was built out of wood in 2019. Finland’s capital Helsinki already has a small wooden district, completed four years ago, and there are state subsidies designed to promote increased wood use in public buildings. Skellefteå, a small, discreet city in northern Sweden nudged its way into must-visit global tourist rankings after the country’s tallest wooden hotel and cultural center opened there in 2022.
A model of the eco-district, to be built out of engineered wood, currently known as Stockholm Wood City, by developer Atrium Ljungberg AB, in Sickla on the outskirts of Stockholm.
A model of the eco-district, to be built out of engineered wood, currently known as Stockholm Wood City, by developer Atrium Ljungberg AB, in Sickla on the outskirts of Stockholm. Erika Gerdemark/Bloomberg—Getty Images
Hyllengren hopes Stockholm Wood City will become “an international showcase” due to its sheer scale. The project is set to become the biggest “mixed-use” wooden neighborhood on the planet—alongside the apartment buildings rapidly taking shape, there’s also a high school opening in the fall, and around 7,000 office spaces will be available within two years.
Like most multi-storey wooden properties, the buildings are largely constructed using an engineered product called CLT (cross-laminated timber). This is made by bonding together layers of wooden panels at right angles, giving it a stiffness and strength that is almost comparable with steel or concrete.
In Scandinavia, it’s easy to produce CLT locally—and sustainably—thanks to the region’s abundance of forests. Around 70% of Sweden is covered in woodland, and in 1903 it became the first nation in the world to require compulsory reforestation. “We don't have a problem where we will run out of wood,” smiles Hyllengren. “We’ve actually got more forest now than we had 100 years ago, because we replant.”
Hyllengren says carbon emissions can be halved in the building construction process, since wood is lighter and quicker to build with than concrete, limiting the use of heavy machinery and energy. The 2020 research from Aalto University and the Finnish Environment Institute also highlights that wood stores carbon rather than emitting it (since it is made from trees which absorb CO2 from the atmosphere as they grow). Plus, if for any reason a wooden building is no longer needed in the future, it is easier to disassemble than concrete, and the wood can be reused or recycled, further extending its life cycle. Using global data projections based on 50 wooden building projects around the world, the researchers concluded that if 80% of new buildings in Europe had structures, cladding, surfaces, and furnishings made of wood, this could sequester up to 55 million metric tons of carbon dioxide per year by 2040. That’s equivalent to 47% of the European cement industry’s annual CO2 emissions.
Lena Dahl, a senior forest expert for WWF Sweden, says the growing trend for building with wood is supported by environmentalists. “Wood has a lower carbon footprint than concrete or steel, so provided that the wood comes from sustainably managed forests it is a better choice,” she says. However, there are concerns about biodiversity loss linked to forestry. Despite reforestation efforts in Scandinavia, Dahl says extensive logging has led to the decline of some plant and animal species, and argues that Nordic forestry companies need to adapt their management practices to ensure nature remains protected as demand for wood increases.
Another potential challenge for the industry is fire safety. But Hyllengren points out that building regulations in the Nordics are among the strictest in the world, and suggests properly designed and treated engineered wood buildings offer levels of heat protection and durability on a par with conventional building materials. “I think it's a bigger talking point abroad where you haven't built with wood before or not as much as we've done,” he says. All of the buildings in Stockholm Wood City are required to have inbuilt sprinklers, and CLT tolerates extremely high heat levels. “It’s hard for the wood to actually catch fire,” explains Hyllengren, and if it does, it will char on the outside from around 300°C (626°F), which creates a protective barrier that limits the spread of flames.
