TRÆ
Denmark’s tallest timber building
The world’s first upcycle timber high-rise and Denmark’s tallest timber tower, TRÆ, is a 78-meter beacon of circular construction, showing that large-scale architecture can combine reused materials, biogenic resources, refined aesthetics and high performance without compromise.
Beyond its environmental performance, TRÆ contributes to the cultural and social fabric of Aarhus. It transforms a former industrial harbor into a vibrant urban setting, offering tactile façades that shimmer with salvaged aluminium and public spaces that invite interaction. The building is more than a workplace, it is a statement of possibility. By turning waste into architectural value and reducing carbon at scale, it signals a new paradigm for architecture worldwide.
Location
Aarhus, Denmark
Area
14,850 m2
Typology
Office
Multifunctional
Collaborators
Artelia
Kaj Ove Madsen A/S
Aarhus Municipality
Realdania
Year
2018 – 2025
Status
Completed
Client
Kilden& Hindby
PFA Ejendomme
Services
Architectural consulting
Landscape Architecture
Innovation
Product Design
Photos by
Anders Nymann Wejse
Giedre Skucaite
Dovalde Butenaite
Rasmus Hjortshøj
The overall concept aligns with our philosophy: form follows availability. This approach celebrates the beauty of waste, transforming discarded resources into architectural value. Located in Aarhus’ former industrial harbor, TRÆ responds to its raw context with facades made from salvaged aluminium sheets arranged to evoke birch bark: mottled, imperfect, and alive. This aesthetic choice turns irregularity into identity, creating a tactile, shimmering surface that changes with light and weather.
The name TRÆ carries three meanings in Danish: tree, timber, and three – reflecting its biogenic materiality, its ecological ethos, and its three interconnected volumes. These three rounded towers rise from a tight site, their soft geometry maximizing daylight and creating a sculptural presence on the waterfront. An undulating pedestrian bridge links the ground level to Aarhus’ new highline, weaving the building into the city’s fabric and inviting public interaction. Ground-floor functions, including a restaurant operated by a social initiative, activate the street, while the “snake” walkway draws people into the site. Beyond architecture, the project embeds social sustainability by involving homeless people in upkeep and hosting a volunteer initiative that provides daily meals for families in need.
‘If we can do things differently, we can help accelerate a movement. This is what we are trying to accomplish with this project. We are all in. We truly believe there is a demand for this type of building from businesses. This type of building and living sustainably will become a part of their DNA.’
Michael Bruhn
Director, PFA Real Estate
User studies and indoor climate measurements confirm that the spaces feel healthy and inspiring. Employees highlight the tactile quality of reused and biogenic materials as creating a sense of calm and authenticity, while natural textures and daylight contribute to a perception of better air quality. Beyond comfort, the innovative concept itself is seen as motivating and forward-thinking, giving users a sense of pride in working within a building that challenges conventions and demonstrates a new way of building.
TRÆ demonstrates that circularity can scale. Life Cycle Assessment shows a 30–50% reduction in embodied carbon compared to a conventional concrete high-rise. By merging technical innovation with social responsibility, TRÆ sets new benchmarks for regulatory compliance and material reuse in high-rise construction.
‘TRÆ does not necessarily adhere to a classic architectural or beauty ideal. It has a different agenda and stands as an energetic reckoning with “well-tested solutions” and zero-error culture, a passionate 1:1 experiment that sparks discussions about what architecture can and should be in our time.’
The jury, Aarhus Architecture Awards 2025
TRÆ was awarded “Best Building”
