Kanalgaden 3 was an office building constructed in 1986 in downtown Albertslund. It had been partially vacant for some time when the municipality was approached with a request to convert it into a senior living community.

Gefion Group, in collaboration with an anthropologist, has developed housing units with shared outdoor and indoor facilities. The transformation was carried out primarily by retaining the original precast concrete structure and reinforcing the existing concrete structure with new foundations and transverse stabilizing concrete walls, to support the new superstructure of precast concrete elements clad with lightweight wooden panels on top, as well as to repurpose the roof surfaces into recreational outdoor communal areas. The complex currently comprises 88 senior housing units ranging from 41 to 99 m², 3 guest apartments, and common areas that foster a sense of community.

The project combines sustainability with architectural quality and creates the framework for safe, social, and functional housing for seniors.

The construction project transforms the three existing floors of the office building, while new sections of varying heights—up to four additional floors—are being built on top. The completed complex will house 90 residences ranging from 41 to 96 m².

Existing concrete structures and facade elements are reused and repurposed, which both reduces the carbon footprint and preserves the building’s structure.

Residents will have access to attractive shared facilities such as rooftop terraces, lounge areas, workshops, an inviting courtyard, and guest accommodations—all designed to foster a sense of community and enhance quality of life. AK83 serves as the architect, while ABC takes on the role of lead engineering consultant.

To accommodate the significant increase in load resulting from raising the building from three to up to seven stories, ABC has developed a new load-bearing structure. This solution ensures both stability and long-term durability in this complex construction project, where functionality, aesthetics, and sustainability go hand in hand.

The project focuses on reusing the existing building’s concrete structures from 1989, which significantly reduces resource consumption and the carbon footprint. To avoid unnecessary reinforcements, ABC has developed a new structural system that preserves the existing facades and optimizes material usage.

Sustainability is a key driving force behind the project, which has earned DGNB Gold certification. This means that environmental considerations and future-proof solutions are integrated throughout the entire development process.

The project is highlighted in the Danish Agency for Social Affairs and Housing’s “Guide to the Reuse of Load-Bearing Structures” (2023), prepared in collaboration with ABC and the Danish Technological Institute, as a green pilot project; the study shows that the transformation has resulted in a 56% reduction in CO2 emissions compared to a similar new construction project.

The project involves the transformation and development of 8,834 m², of which 5,058 m² consists of existing floor space from the original office building, corresponding to a 75% increase. Looking at the distribution of floor space in the transformed building, 43% of the floor area comes from newly developed space, while 57% comes from the existing structure.

When comparing CO₂ emissions, the transformation and creation of new square meters result in 1.9 kg CO₂/m²/year, which also corresponds to 43% of the CO₂ emissions for the scenario in which the building would have been demolished and rebuilt. This is despite the need to reinforce the existing structure, which could not bear any additional load.

You can read more about this case study by clicking here.