Circular economy: Getting the circulation going
See the original article, published in Nature by Barbara Kiser - 13 April 2016.
With sustainable construction company BAM Construct UK, I helped to develop buildings that are fit for purpose and perform as intended for their whole lifetime. My focus is passive design, renewable and modular materials and buildings with low energy demand. Major influences have been the Cradle to Cradle approach and architects who explore biomimicry, such as Antoni Gaudí and Santiago Calatrava. The circular-economy model has provided a larger organizing idea with which to synthesize these strands, because it is predicated on using materials that can retain asset value for longer and can eventually be taken back to their biological or technical cycles — reused, repurposed or remanufactured — to reduce waste and unlock new economic opportunities.
BAM's first 'circular' pilot project is the town hall in Brummen, the Netherlands. The client had outgrown its existing building and needed a larger space for at least another 20 years. With Rau Architects in Amsterdam and its sister company Turntoo, we offered a 'building as material bank' to maximize value for the municipality (given that it may wish to move its offices in time). Our competition-winning offer took into account the full costs of the building over its 20-year occupancy, and provided greater price certainty than conventional approaches. Key to this was that after 20 years, components of the building (such as structural timber and metals) could be returned, under contract, to suppliers, unlocking a minimum 20% of their residual value. This 'closed loop' approach reduces manufacturers' reliance on virgin materials and diminishes price volatility.
Technical elements designed for disassembly include the overall shell, cladding, internal partitions and cooling. The design avoids coatings and resins wherever possible to make parts interchangeable and allow separation of valuable raw materials. Components have to retain value over time, so we bring partners such as electronics suppliers and manufacturers Philips and 8Point3 to the table. Many of our projects also incorporate prefabricated elements, so design proceeds through a standardized procurement process to reduce production costs, as well as increasing residual values for key components to more than 50%.
Transparency through the supply chain is essential, so our work has to be highly collaborative.
Beyond materials, we look at systems and processes such as the cost of dismantling, logistics, and storage of components, how it is done, and by whom. We decide who takes responsibility and ownership of the materials during and after the use phase. Transparency through the supply chain is essential, so by its very nature, our work has to be highly collaborative. Sander Holm, a key sustainability leader at one of BAM’s construction and engineering company BAM Bouw en Techniek, notes, “manufacturers and suppliers must sit at the table together as soon as possible. This kind of co-creation delivers more innovation, and also a higher residual value.”
We had also initiated a research project with The Great Recovery, a sustainability network launched in 2012 by the RSA (formerly the Royal Society of Arts) in London, to encourage designers, manufacturers and recyclers to co-create solutions for material reuse. We were using 'teardown' methodology, in which production systems are scrutinized to tease out problems and opportunities for 'designing up' to circularity. Our team’s focus was on processes key to the circular economy, including building-information modelling, a digital shared-knowledge resource used to make decisions about a building's life cycle, such as resource productivity.
At the moment, there is no guarantee that buildings or products designed with natural materials or for deconstruction will be reused. And there is little information on existing building stocks and their potential for sustainable renovation. This must change. One of the construction industry’s challenges is the need to educate the value chain — encouraging our industry towards procurement with an eye to the longer term, and switching to 'performance or take-back' contracts, which keep the responsibility for maintenance, durability and replacement of parts with suppliers. Through the UK Supply Chain Sustainability School, BAM had hosted a series of workshops to work through some of the barriers to circular-economic models. Building on our status as leader in the Dutch Benchmark Circular Business Practices 2015, we are gradually moving from focusing on waste reduction in the construction process to reducing waste over a building's life cycle.