Træ High-rise Building

English description provided by the architects.

Located in Aarhus' raw harbor area, marked by industrial traces and social inequality, the project sought to merge ecological, social, and architectural renewal.

The client's ambition was clear: create a building that accelerates a movement toward circular construction. "If we can do things differently, we can help accelerate a movement. This is what we are trying to accomplish with this project.

Conceived as a radical experiment, the project set out to prove that a high-rise could be built from timber and waste without compromising safety, performance, or economy.

The ambition to integrate as many reused materials as possible added further complexity, demanding new technical standards and regulatory pathways.

Intensive collaboration between architects, engineers, contractors, and municipal authorities was essential, alongside iterative innovation processes and full-scale fire tests for unconventional components such as wind turbine blades repurposed as solar shading.

The overall concept aligns with Lendager's philosophy: form follows availability. This approach celebrates the beauty of waste, transforming discarded resources into architectural value.

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.

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.

Structurally, TRÆ combines glulam columns and CLT floor slabs, with low-carbon concrete cores ensuring stability and fire safety. Nearly all visible surfaces are reused, upcycled, or biobased.

Wind turbine blades provide solar shading, while reused windows, waste textiles, and PET felt form acoustic surfaces.

Interior finishes include reclaimed timber flooring and panels, while mature trees relocated from municipal sites reinforce the "tree" concept and create an immediate green setting. 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.

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.

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.

'TRÆ does not necessarily adhere to a classic architectural or beauty ideal.

- Excerpt from the jury of Aarhus Architecture Awards 2025, where TRÆ was awarded "Best Building"