Understanding the challenges of circular economy construction through full-scale prototyping

Applying the Circular Economy paradigm in the built environment requires buildings to be designed for deconstruction and material recovery. Achieving circularity is complicated by the fact that requirements for deconstruction are at odds with most current mainstream construction techniques. The widespread adoption of single-use fixings, adhesives and composite materials mean that it is rarely economically or technically feasible to recover materials. To address this issue a highly modified structural timber framing solution has been designed that separates traditionally dependant layers of a buildings weather resistant envelope. As part of evaluating the viability of this modified framing solution a full-scale building prototype was constructed. The prototype adopted an entirely modular, prefabricated lightweight structural frame with provision for the reversible fixing of structural cavity battens, cladding, purlins and internal linings. Experimental thermally modified plywood cladding materials, using a bespoke concealed bracket, were also designed and deployed. The design-build process worked effectively to highlight limitations within the proposed circular building system, however it was observed that many of the issues found could have been identified using detailed BIM modelling (down to a fixing level).