Value network mapping applied to the flat glass sector: constraints and leverage points for circularity.

Architectural flat glass is a fully recyclable material but continues to follow a linear, wasteful path from renovation and demolition sites into landfills or low-value recycling. To make the shift towards circularity, understanding the whole flat glass network is essential. Therefore, the present paper identifies constraints and leverage points for circularity from a systemic perspective. Departing from literature and in-person discussions with network actors, value network mapping is applied to conventional practices, a transition tool to define essential missing roles, relations, and transactions. First, the roles and general relations are mapped, and step-by-step the value transactions and flows are detailed. An alternative circular value network map was then developed in which systemic changes are suggested to improve reuse, repair, and recycling applications. Leverage points are identified, such as learning from best-practices, sharing knowledge between actors, creating awareness, and creating incentives for the actors. From these findings, specific interventions in the conventional value network of flat glass can be conceived and planned as a sustainable transitions experiment (e.g., in the context of a living lab project initiated by governmental or private forerunners), or as an enduring redefinition of some roles and relations in the construction sector with a systemic result.