The project describes a building extension in which the added floors are designed to utilize the demolition waste from other construction sites. An industrial building in Winterthur, Switzerland will be repurposed to create a series of 12 units/studios. The design process starts with the collection and classification of building elements sourced from dismantling and demolition operations, and the identification of their potential for recycling. An external steel staircase, aluminium windows, metal corrugated sheets, roof insulation and photovoltaic modules are all salvaged from previous construction and given a second life. Steel beams are reused for the new structure, old façade stone cladding is redeployed as floor tiles.