Defining closed-loop material cycle construction

The principle of closed-loop material cycle (CLMC) construction can be described as a construction constituting materials and building elements that can be recovered from buildings and infinitely recycled through natural or industrial processes. Moving from the conceptual toward the practical, the paper identifies and defines criteria by which building materials and elements can be assessed in terms of forming part of a CLMC. The characteristics of CLMCs and their relevance to the building industry are considered, and a set of criteria for closed-loop cycle (CLC) materials is formulated, drawing on existing research and guidance on natural recovery and design for deconstruction and recycling. A pilot CLMC assessment of selected building technologies suggests CLMC construction is technically feasible. The developed CLMC criteria could be used to encourage the design of buildings associated with less waste and environmental impacts. The more comprehensive nature of a CLMC as an approach to waste minimization broadens the options for waste reprocessing in buildings. The implications for mainstreaming CLMC at policy and practical levels for different actors are considered.