To combat climate change, the disappearance of nature, and resource scarcity, the entire construction sector should move towards a circular economy model. Although the circular economy is a popular discussion topic, there are still only a handful of actual completed projects. This is not for a lack of potential methods.
The basic principles of a circular economy include adapting to the environment’s carrying capacity and eliminating emissions and waste. For construction, this means using the existing building stock as efficiently as possible. In the choice of materials, preference is given to materials already in circulation and to low-emission materials that have no harmful health effects. Designs consider how the building can be converted to different uses and disassembled in a way that enables the efficient reuse of the materials.
The following European sites are excellent examples of how circular economy principles can be implemented in the construction industry.
Baubüro in Situ
The Swiss architectural firm Baubüro in Situ is a pioneer in the circular economy. The company’s circular economy projects make clever use of the existing building stock, recycled materials and low-carbon natural materials.
A great example of this is “K. 118”, which involved renovating an old factory building and adding a three-story residential complex on top. The addition’s frame is mostly built from reused steel parts, and it is an example of reusing windows. The exterior walls have wooden structures, straw insulation, clay plastering on the inside and recycled sheet metal on the outside. Recycling, ease of maintenance and the gentle passage of time are prominent inside and out, visibly stepping away from the minimalism that has been popular for so long.
Brummen city hall
Designed by RAU architects, the extension of Brummen Town Hall takes a different approach to the circular economy. This project shows how circular economy principles can be followed in design and construction. The carbon footprint is small, and everything was designed with dismantling and reuse in mind. The timber-framed building is designed to be dismantled with ease into separate parts that can be reused elsewhere. The joints are easy to open. In fact, they have been left in plain sight as part of the architectural expression.
The circular economy approach was woven into the procurement contracts. Instead of a standard procurement contract, the project used a more flexible, economically and environmentally sustainable “leasing” approach. Namely, the building component suppliers agreed to buy back 90% of the materials at 20% of their original price once the building is dismantled. This sustainable model resulted in 30% lower lifecycle costs compared to other similar buildings in the area.
Text: Ninni Westerholm
Read the article in Finnish: Kiertotalousesimerkkejä maailmalta