Circular economy

The proportion of a product, by mass, made from recycled rather than virgin material, usually split into post-consumer content (from products discarded after use) and pre-consumer or post-industrial content (from manufacturing waste). Definitions and self-declared claims are commonly made with reference to ISO 14021.

Designing products and buildings so that components can be separated non-destructively at end-of-life for reuse, remanufacture or high-grade recycling, for example by favouring mechanical fixings over permanent adhesive bonds. It is a core enabler of circular economy approaches in construction and manufacturing.

A recycling system in which material recovered from a product is reprocessed into the same or an equivalent product, retaining its quality and value. It contrasts with open-loop routes, where recovered material enters a different and often lower-grade application.

The stage in a product's life cycle when it is removed from service and must be reused, recycled, recovered or disposed of. End-of-life scenarios are a required consideration in life cycle assessment and increasingly influence material selection for composites and roofing systems.

Recycling in which the recovered material is of lower quality or value than the original, so it can only be used in less demanding applications. Mixed glass fibre composite waste, for example, is often downcycled into filler or aggregate rather than new structural laminate.