Europe's 18-story timber skyscraper is rewriting the rules of urban construction

Europe's commitment to green construction has turned what sounds like a children's book premise into reality. In Brumunddal, a small city about 140 kilometers north of Oslo, an 18-story tower rises above the surrounding buildings on the shore of Lake Mjøsa. From the outside it looks like any other high-rise — but the structure holding it up is not steel and concrete. It is wood.

The building is Mjøstårnet, standing 85.4 meters tall and housing apartments, offices, a hotel and restaurants. When it was completed in 2019, it was the tallest timber building in the world. Taller wooden structures have since been built, but Mjøstårnet remains one of the most cited examples of a high-rise that relies on timber as its primary structural material, with no steel frame or concrete core.

The Guardian recently spotlighted Mjøstårnet as part of a broader examination of whether modern cities — long dependent on concrete and steel — could be built from wood.

The key to Mjøstårnet is mass timber, a category of large-scale engineered wood products. The building uses glued laminated timber, or glulam — layers of processed wood bonded together into a single massive structural element — as well as cross-laminated timber, or CLT, made by stacking and gluing wood panels in alternating directions.

According to the Guardian, Mjøstårnet's large glulam columns, beams and trusses were precision-cut to the millimeter at a nearby factory, then transported to the construction site and assembled — a process of fabricating giant components in a controlled environment and fitting them together like a kit.

The ambition was clear from the start for developer Artur Buchardt. "The height was important," he told the Guardian. "It had to be a signal of what was possible."

The biggest driver of interest in timber high-rises is the construction industry's carbon footprint.

According to the Guardian, the built environment — encompassing construction as well as heating, cooling and lighting — accounts for about 37 percent of global carbon emissions. Concrete manufacturing alone is responsible for 7 to 8 percent of total emissions. That is largely because producing cement, concrete's core ingredient, requires heating limestone to extremely high temperatures, consuming large amounts of energy and releasing carbon dioxide in the process.

Timber has the opposite profile. Trees absorb carbon dioxide from the atmosphere as they grow and lock it inside their fibers. When a felled tree is used as a building material, that carbon remains stored within the wood.

The Guardian reported that constructing a typical mid-rise building from steel and concrete generates roughly 1,500 to 2,000 metric tons of carbon dioxide, whereas building the same structure from timber can store 600 to 1,000 metric tons of carbon dioxide within the building itself.

Mjøstårnet has not eliminated concrete entirely. Timber buildings are lighter than steel-and-concrete structures, which means they can sway more in the wind as they rise higher. Mjøstårnet used concrete on some floors to reduce movement in the upper stories.

Fire is another challenge timber construction must overcome. However, mass timber behaves very differently from the thin planks most people picture. When thick timber is exposed to fire, a layer of char forms on the surface that slows the spread of flames into the interior — a property that engineers factor into decisions about structural thickness and fire-safety design.

Driven by advances in these technologies, experiments in timber construction are expanding beyond individual high-rises to entire urban districts.

In Sickla, south of Stockholm, Swedish real estate developer Atrium Ljungberg broke ground in 2024 on Stockholm Wood City, billed as the world's largest timber urban development project.

When complete, the development is planned to include housing for about 2,000 households and workspace for 7,000 jobs, all centered on timber buildings. Construction of the first residential building has begun, with completion targeted for 2026.

Timber construction is not yet ready to replace conventional methods outright, and cost remains one of the biggest obstacles. Mjøstårnet required about 100 million pounds to build. The Guardian estimated that an equivalent building in steel and concrete would have cost roughly 10 million to 15 million pounds less.

A further question is whether sustainable forest management can keep pace if demand for construction timber surges. Reducing emissions during construction counts for little if indiscriminate logging erodes forests' capacity to absorb carbon in the first place.

Even so, experiments in using timber for tall and large-scale buildings continue across Europe. Wood is shedding its image as a finishing material or a resource for low-rise construction and is beginning to be used as a structural material capable of reducing the overall use of steel and concrete.

Rune Abrahamsen, the structural engineer behind Mjøstårnet, told the Guardian that when he was a university student in the 1990s, almost everyone studied concrete, steel and aluminum structures, and only a handful of people worked with timber.

More than 30 years later, the 18-story building he designed stands on the shore of Lake Mjøsa. Buchardt acknowledged that eliminating concrete and steel entirely was not realistic, but said their use "can be reduced significantly."

Europe's experiment continues — testing whether the materials that define the modern city might, once again, be wood.