A concrete coffee house that can be dismantled again within just a few days: The Grüze Innovation Lab has been located on St. Gallerstrasse in Winterthur since May 2024, directly beside Grüze railway station and the Küng coffee roastery. Beneath its open roof are an exhibition area, a stage and a small bistro.
From two decades of research to the first building structure
The construction method behind it is known as CPC – carbon prestressed concrete. It was developed at the ZHAW School of Architecture, Design and Civil Engineering, where Josef Kurath’s research group has been working on prestressed carbon concrete without steel reinforcement for more than 20 years. The panels are three to four times thinner than conventional concrete elements, resistant to corrosion and are precisely milled and assembled in the factory based on digital design data. Disassembly and reuse are taken into account right from the outset.
Opening of the Grüze Innovation Lab in Winterthur
Three partners, one building component for hire
The building was made possible through a partnership between three organisations: the Winterthur Civil Engineering Office provides the site, the ZHAW provides the technology and Holcim Switzerland supplies the CPC elements. In keeping with the product-as-a-service model, the elements were rented rather than sold. Once dismantled, the panels can be refurbished and reused elsewhere.
Compared with conventional reinforced concrete, the building thus reduces CO₂ emissions and material use by around 75%, while eliminating the use of steel altogether. This makes the Innovation Lab the first building structure to be constructed using reusable carbon-concrete elements, initially as a temporary structure for ten years.
Josef Kurath
Founder of CPC AG and Professor at the ZHAW School of Architecture, Design and Civil Engineering
“What we actually wanted with this first building project using these slabs was to demonstrate what can be achieved with CPC construction. We wanted an object that showcases all the complexities that can be involved in a structural slab in building construction.”
