Mjøstårnet: The World's Tallest Timber Building in Brumunddal

Introduction

On the eastern shore of Lake Mjøsa, Norway's largest lake, the small town of Brumunddal rises from the farmland of Hedmark. For most of its history, this was a quiet agricultural and industrial hub, known for sawmills and timber yards. But in March 2019, Brumunddal entered the global architectural spotlight with the completion of Mjøstårnet, an 85.4-meter, 18-story mixed-use tower designed by Voll Arkitekter. It is the world's tallest timber building, a title it still holds today. The tower is not just a record-breaking stunt; it is a serious experiment in what engineered wood can do at high-rise scale, and a bold statement from a country with a deep forestry tradition.

The Building and Its Design

Mjøstårnet stands as a slender, tapering monolith clad in timber, rising from a low-rise base that houses a hotel, apartments, offices, and a restaurant. The tower itself contains 72 hotel rooms on the lower floors, 33 apartments above, and a top-floor restaurant and terrace with panoramic views over the lake. The design is straightforward and functional, with a rectangular footprint that eases into a slight curve on one side. The facades are a rhythmic composition of vertical timber battens and large windows, giving the building a warm, organic texture that changes with the light. Inside, exposed glulam columns and beams, as well as cross-laminated timber (CLT) walls, are left visible in many areas, celebrating the material's structural role.

Voll Arkitekter, an Oslo-based practice led by Øystein Elgsaas and Siv Stangeland, approached the project with a clear ethos: to use timber not as a decorative afterthought but as the primary structural material. The result is a building that feels both monumental and intimate, with a distinct Scandinavian character—clean lines, natural materials, and a quiet confidence.

Engineering with Wood at High-Rise Scale

The real story of Mjøstårnet lies in its structure. The tower is built around a core of two parallel CLT shafts that house elevators and stairwells, providing lateral stability. Around this core, a frame of glue-laminated timber (glulam) columns and beams supports the floors, which are made of prefabricated CLT panels. The glulam elements are massive: some columns reach 85 centimeters in diameter, and the largest beams are over 60 centimeters deep. The entire structure—except for the concrete foundation and the steel connections—is wood.

This was a pioneering endeavor. When the design began in 2016, there were no European standards for tall timber buildings beyond about 7 stories, and no empirical data on how a timber structure would behave under wind loads at 85 meters. The engineers at Sweco, led by Rune Abrahamsen, had to develop their own solutions. They used a combination of finite element modeling and extensive wind tunnel testing to predict the building's sway and vibrations. To keep the structure stiff enough, they added a post-tensioned steel cable system within the walls, a hybrid approach that was later abandoned in favor of pure timber in the final design, as the CLT core proved sufficient.

One of the biggest challenges was the connection details. Steel plates and dowels are used to join the massive timber elements, but these had to be designed to allow for the natural movement of wood—its expansion and contraction with moisture. The team also had to ensure fire safety. In timber, fire is a double-edged sword: the material burns, but it also chars in a predictable way, creating an insulating layer that protects the inner core. By oversizing the structural elements, the engineers could guarantee that even after a severe fire, the remaining wood would still bear the load. Mjøstårnet is designed to withstand a 2-hour fire without collapsing, a requirement that surpassed normal building codes.

Carbon Arguments and Sustainability

The most compelling argument for Mjøstårnet is its carbon footprint. Concrete and steel are responsible for a significant share of global CO2 emissions—about 8% and 7% of annual emissions, respectively. Timber, on the other hand, is a renewable material that stores carbon. The wood in Mjøstårnet, which comes from Norwegian forests, sequesters an estimated 1,100 tonnes of CO2. If the building had been built with concrete and steel, it would have emitted roughly 3,000 tonnes of CO2. So the net difference is over 4,000 tonnes of CO2—a substantial saving for a single project.

But the carbon story is not straightforward. The production of glulam and CLT requires energy for drying, laminating, and pressing, and the steel connections and concrete foundation add to the footprint. Nevertheless, lifecycle assessments show that timber buildings have a significantly lower embodied carbon than conventional structures, especially when the wood is sourced from sustainably managed forests. Norway is a leader in this regard, with a long history of forestry and a strong legal framework for replanting.

Mjøstårnet is also designed for deconstruction. The structural elements are connected with steel plates and bolts, which can be disassembled and reused. This aligns with the principles of the circular economy, where buildings are seen as material banks rather than permanent waste.

Norway's Wood Engineering Leadership

Norway has a unique relationship with wood. For centuries, it was the primary building material for everything from stave churches to farmhouses. But in the 20th century, concrete and steel took over, and timber became associated with low-rise residential construction. In recent years, however, there has been a resurgence, driven by a combination of environmental awareness, government incentives, and a desire to innovate. Mjøstårnet is the most visible symbol of this revival.

The country has invested heavily in research and education in timber engineering. The Norwegian University of Science and Technology (NTNU) in Trondheim has a dedicated department for wood structures, and the research institute SINTEF has developed new testing methods. This expertise has been applied to a range of projects, from the 18-story Treet in Bergen (which held the world record before Mjøstårnet) to the new airport in Oslo, which uses massive glulam beams. Norwegian architects and engineers are now exporting their knowledge, advising on timber towers in Sweden, Austria, and even the United States.

Mjøstårnet's role in this narrative is crucial. It proves that timber can compete with concrete and steel in the high-rise market, not just in theory but in practice. The building has been monitored extensively since its completion, with sensors measuring moisture, movement, and vibrations. The data so far is reassuring: the structure behaves as predicted, and the wood is performing well.

Conclusion: Why It Still Matters

Three years after its completion, Mjøstårnet remains a landmark, both physically and symbolically. It is a reminder that the construction industry, which has been slow to change, can indeed evolve. The building has inspired a wave of timber high-rises around the world, from the 87-meter Haut in Amsterdam to the 84-meter HoHo in Vienna, and many more are on the drawing board. But beyond the records, Mjøstårnet matters because it challenges our assumptions about what is possible. It shows that we can build tall with a material that grows from the ground, that sequesters carbon, and that creates a warm and healthy environment for people. In a time of climate crisis, that is a message of hope. As we look for ways to reduce the carbon footprint of our built environment, Mjøstårnet stands as a proof that we can have our cake and eat it too—if we are willing to embrace the wood that surrounds us.

In Brumunddal, a town that has always lived by the forest, the world's tallest timber tower is not just a feat of engineering; it is a return to roots. It shows that the future of architecture can be rooted in the past, and that the oldest material on earth still has new tricks to teach us.