Make or break the loop: a cross-practitioners review of glass circularity

End-of-life insulating glass units (IGUs) continue to follow a linear, wasteful path from renovation and demolition sites into landfills or low-value recycling. To get one step closer to the question of how to close the glass loop, this exploratory research outlines a cross-practitioners review of glass circularity in conventional Flemish and Brussels practices. A series of semi-structured interviews with network actors and an extensive literature study is conducted to identify existing and missing circular practices and to pinpoint the key barriers and opportunities. In general, the circular strategies repurpose and open-loop recycling of end-of-life IGUs are successfully applied in Flemish and Brussels construction practices. Repair, reuse, and closed-loop recycling remain unexplored. The main barriers are the lack of collaboration, logistic and labour costs to collect end-of-life IGUs, its complex disassembly, the lack of legal incentives and the conservativeness of the construction sector. Case studies, the high recycling potential and the scale of projects are found to be the main opportunities for glass circularity. The cross-practitioners’ insights in this paper contribute to close the glass loop and to further development and up-scaling of circular strategies