The building sector is responsible for approx. 40% of green-house gas emissions, up to 40% of raw material consumption and more than 50% of global waste. Billions of tons of valuable materials are stored in our built environment but can’t be reused, because “everything is baked together” (with concrete, adhesives, etc.) and can’t be separated as a result of our linear production processes. These numbers underline the enormous ecological, social and economic potential of changes in this industry. To unlock this potential, transformative, circular and scalable solutions are required. This is what F2K is aiming at.