This paper describes opportunities to apply circular economy principles to the lifecycle of architectural glass products.

Flat glass manufacturers are rightly focused on optimising their operational carbon, currently that focus prioritises new furnace technology, incorporating fuel switching, waste heat recovery and carbon capture. Increasing the use of recycled content with high quality, sorted glass cullet, collected from existing buildings can play a crucial role in reducing the energy demand and carbon footprint of new glass products.

The embodied carbon of glass and the benefits of increased cullet use in the production of new flat glass is widely understood and demand for these materials far outstrips the supply of quality cullet materials. Research by manufacturers have shown that both higher percentages of overall cullet and post-consumer cullet is feasible. Despite understanding the benefits, there are both real and perceived limitations to the implementation of post-consumer cullet in flat glass.

This paper identifies unfulfilled potential to recover end-of-life glazing for reuse in material production by applying disassembly techniques to collect materials ready for reuse or recycling. The paper explores two key technical barriers, the separation of insulating glass units and laminated glass.

Through identification of the constituent materials in these products and descriptions of new methods of separation the paper defines second uses for materials collected including not only the glass but also spacer bars, seals and interlayer materials.

This report will discuss fledgling industry roles, new supply loops and technology developments   necessary to successful implement these principles on real projects.