Storage and maintenance building made from reused construction products
In the summer of 2025, a new maintenance and storage building was completed in Mustikkamaa, constructed almost entirely from reused construction products.
Circular construction pilot project
Can an entire building be constructed from reused components? What can we learn from circular construction practices? These questions sparked the Closing Loops pilot project, which resulted in a maintenance and storage building that is exceptional in the Finnish context – built almost entirely from reused construction products.
The collaborative project began with a design competition aimed at students, organized by Helsinki Circular Economy Cluster Program and Aalto University. The winners were siblings Johanna and Markus Saarela with their proposal “Lippa.” Stara, the City of Helsinki’s construction service provider, began building work in the summer of 2024.
When the facility was completed in the summer of 2025, it was taken into use for the maintenance of sports and recreational services in Mustikkamaa and its surrounding areas. The pilot advanced the integration of circular-economy solutions into construction practices and serves as an important example for future building projects that can build on its lessons.
How the storage building made from reused components was built
Watch the key moments and highlights of the construction project.
Advancing circular construction in Helsinki
Closing Loops is a collaborative project organized by Helsinki Circular Economy Cluster Program. One of its key aims is to accelerate circular construction by bringing together actors in the building sector and combining their expertise. The City of Helsinki is continuously seeking ways to reduce the carbon footprint of its own construction activities in line with its city strategy.
How circular construction is reflected in the project
Building with reused materials differed somewhat from a conventional process. For example, design decisions were finalized only after the availability of the required materials had been confirmed.
A circularity consultant from Spolia Design sourced the building components from various locations across Finland. In addition to the load-bearing frame and exterior cladding, reused materials were applied to features such as the interior partition walls of the staff facilities and the water and fixed fixtures. The building’s windows were repurposed from the old windows of Helsinki’s Postitalo.
Before installation, all components were cleaned and, when necessary, refurbished. For instance, the Postitalo windows were fitted with new interior frames made from fresh wood, along with new glazing. To ensure the suitability of the materials for construction, site-specific verification and CE markings were used. Depending on the building component, quality assurance included visual inspection, bending fracture tests, water-tightness tests, frost-resistance tests, delamination testing, and strength-class markings.
The condition of the reused materials will continue to be monitored for several years after the building’s completion. Two doctoral dissertations are currently being prepared at Aalto University, examining aspects such as the project’s carbon footprint as well as the design and procurement processes.
Where the materials came from?
Architecture that blends into its surroundings and reveals the history of its materials
The storage building was designed for a sensitive landscape setting, close to the meadows and exposed bedrock of Mustikkamaa. Its architectural expression is defined by a clear, elongated form and an asymmetrical gabled roof. The vertical division of the façades breaks up the long elevations, enabling flexible design and replacement of reused materials without visual compromise.
The load-bearing frame is made of glulam. Its patina and original markings were left visible to reveal the history of the material. The façade combines reused aluminum cassettes with board cladding crafted from glulam, intentionally exposing the joints of the laminated timber. The dismantled aluminum cassettes were cut to size and installed reversed from their original orientation, with the seam facing outward. This highlights the beautiful tonal variations of the aluminum surface and the vertical seams that complement the overall design.
Thanks to modular construction, the building can be relocated if needed. Most of the building components have been designed for easy disassembly and reuse at the end of the building’s life cycle.
From design to completion: Closing Loops in the words of the project team
Project partners share how the pilot progressed and what they learned along the way.
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