For this special issue, sustainability and safety are discussed through the tropes of both material and work process substitution. As an architecture and industrial design team, we examine the potential of William McDonough’s and Michael Braungart’s “cradle to cradle” material methodology, and David Pye’s “the workmanship of certainty” as relevant to the construction industry. Locating and revisiting the tenets of Gottfried Semper’s Stoffwechseltheorie, alongside contemporary critiques, demonstrates that if historically, material and technique substitution led to architectural innovation, the same conditions exist today. To demonstrate a contemporary Stoffwechsel (material substitution) a formwork prototype was constructed at the University of Canberra’s Workshop 7, by substituting timber with plastic, and 3D-printing the formwork. This prototype demonstrates a type of “technical nutrient” that is both recyclable as plastic, and reusable as formwork. This reveals the potential of substituting materials and processes not only to achieve material recovery, but rather, aiming for material recycling, reuse, or upcycling, therefore reducing socio-environmental risks in construction.

This article traces two generations of urban thinking embedded within Canberra’s centre and a subtle though important transition from a late-modern idea of civic design to a neo-avant-garde underst...