KA-RZ: A Sustainable Building Material Made from Coffee Grounds
Every day, billions of cups of coffee generate vast amounts of coffee grounds as waste. KA-RZ explores how this overlooked resource can be transformed into a sustainable building material. This approach combines sustainability, efficiency and technological innovation and opens up new possibilities for environmentally friendly construction.

From idea to innovation
The idea originated from Olaf Elze, director of the German company K-MÄLEON, a partner in the GreeNest project, when he realised that the whole world drinks coffee and that countless tonnes of coffee grounds end up in the bin every day. Instead of treating it as waste, Elze saw that this organic raw material has valuable properties. Coffee grounds are rich in organic components and can serve as a sustainable raw material for the production of a high-performance insulating material. The aim was to develop a building material that is not only environmentally friendly but also has excellent insulating properties and can be used in a variety of ways in the construction industry. In addition, the product promotes circularity: after use, the materials used can be fully recycled and returned to the production cycle.

Access more information on GreeNest website and download the full press release here.