What if building components were decoupled from the single-use paradigm – and were sold and resold and resold again? Enabling greater reuse of building materials is a strategy that is best applied at the very beginning as part of sustainable design. Circular lifecycles increase the potential to reuse building materials by factoring-in the need for components to be recovered, inspected, stored, and resold. Institutions that make this exchange, verification, and re- valuing possible could be exciting new actors in the material supply chain.

At the 6th LafargeHolcim Forum for Sustainable Construction, Maarten Gielen, Designer, Manager & Researcher at Rotor, Belgium explored this theme as part of the workshop “Changing paradigms: Materials for a world not yet built”. Rotor is a cooperative design practice that investigates the organization of the material environment. Maarten Gielen has been active as Project Manager of Rotor Deconstruction, a spin off that organizes the dismantling of buildings and the reuse of building components in the city of Brussels.

Brussels has just over one million inhabitants. This relatively modest urban population generates more than 6 million tons of building and demolition waste per year – and at the same time imports around 8 million tons of building materials. Rotor Deconstruction focuses on the potential re-use of this material: “Most of the time the construction material isn’t replaced because its natural life span is over, but because the new owner wants different materials used,” says Maarten Gielen (pictured right).

Building component exchange companies survey buildings that are to be demolished or renovated and assess the feasibility of reclaiming components; act as experts in carefully extracting and transporting the materials; sort, clean, and store the components; and build a client pool of contractors and designers to whom they can resell. Their role as guarantors for the resold components is equally important. Without a legal entity that can be held liable in the event of failure, building components – especially structural assemblies that need to be retested – often cannot be reused. Specifications also play an important role in facilitating or hindering reuse. They could be assessed and potentially rewritten to enable the use of reclaimed materials wherever possible by, for example, allowing for irregular lengths.

Strategies to re-materialize construction

As the key input to the Forum, the publication 22 Propositions offers strategies for both the material supply chain and material use in buildings. The propositions aim to “re-materialize” construction by rethinking the building material cycle from extraction to processing, design, transport, installation, maintenance, and removal.

The changes proposed would contribute to a construction industry with a smaller ecological footprint and a shift away from the unsustainable assumption that raw construction uses significant amounts of material. Rethinking materials and material use also has tremendous potential to lower greenhouse gas emissions and reduce dependence on resource extraction.

The Materials Book to be published by Ruby Press Berlin in late 2019 will feature the essence of 22 Propositions as well as a selection of additional proposals to re-materialize construction derived from the findings of the Forum.

Read 22 Propositions (flip book)

More about the LafargeHolcim Forum 2019