Ivanova Konstanca from Stride Treglown outlines the benefits and features of a circular economy – one where waste and pollution are eliminated, products and materials are recirculated ‘at their highest value,’ and natural systems are regenerated
Circular economy goes beyond reducing carbon, instead providing positive impacts for the environment and nature in general; it is integral to addressing the current climate and biodiversity crises that we find ourselves in.
The built environment is one of the biggest CO2 emission producers, contributing 45% of the UK’s material footprint and roughly 38% of the country’s emissions, alongside agrifood, manufacturing and processing, and services (Circle Economy, UK Gap Report). Apart from assisting with whole life carbon reduction, circular principles provide environmental and financial value (as shown in the UKGBC report ‘Insights on how circular economy principles can impact carbon and value’). Not only is circular economy a shift in the process in which we design and construct buildings, it’s primarily a shift in thinking about the environment and the availability, impact and reliance on finite resources.
Challenges with adopting a circular economy
The topic most lagging behind at present is regarding the measurement of circularity and therefore benchmarking of projects – despite it being researched and having several assessment tools already produced by stakeholder, such as Regenerate and
the Circular Buildings Toolkit. Though there is a considerable amount of research – and several proposals for circularity metrics – a consistent methodology is absent, leaving a gap in the ability to compare project performance and making the establishment of performance targets very difficult.
Currently, demolition and new build is cheaper than deconstruction and refurbishment. Due to the unknowns of what might be found at an existing building and how long this might impact the programme, many clients prefer to demolish and build anew. Similarly with regards to materials, it is cheaper to buy new materials than to salvage and utilise reused ones. The uncertainty of this process, the re-certification of the materials, the fact that this procedure is still new and unfamiliar, makes it “unsustainable for a single client to bear the cost” (Elliot Wood, ‘Full Circle to Reuse’).
To lower carbon emissions of a project, one must be aware of what routes are available to addressing carbon reduction in buildings, and understand the impacts of each route. Similarly, understanding circularity and how its principles work is key. There is a vast array of organisations which identify the principles of circularity differently – and there are some misalignments. It’s important to understand what they are and how they work together, since circular economy is a holistic way of thinking about waste prevention, recirculation of materials and regenerating systems. Clearly establishing the value that circularity would bring to a project and the purpose of the principles applied would also assist in their successful implementation.
The identification of buildings (both existing and new build) as material banks or material stores, ready to be mined at the end of their life, is a concept widely researched by the BAMB 2020 Horizon programme. Successful reuse of a material and its deconstruction relies to a large extent on the information available for this material and its existence and upkeep. The concept of ‘material passports’ is an example of how this could be done – a document for each material which holds all the important information related to that material, which you need throughout the various stages of its life, including deconstruction or reuse. While several years ago this concept was largely conceptual, working platforms already exist and are used in pilot schemes both in the European Union and within the United Kingdom.
The gathering and storage of this information could also mean changing the way consultants such as architects and engineers produce their working information and building models. 3D modelling software is becoming increasingly more capable of storing such large amounts of information and extracting it via different platform plug-ins for various tasks, i.e. to populate bills of quantities.
‘Building for deconstruction’
One end of life principle of circularity is Designing for Deconstruction (DfD). To enable deconstruction and the effective recovery of materials for reuse, the building can be seen as an ‘onion’, and each layer – i.e. Stuart Brand’s ‘Building in Layers’ – should be considered separately and then in unison with the others. This would mean each layer is designed with its respective life expectancy in mind and steps to mitigate its replacement/disassembly are taken into account in the design stage; this could be applicable for a separate layer or for the building as a whole.
While deconstruction is not yet widely accepted and practical examples of building case studies are limited and more concentrated on separate materials or systems, a similar process – Designing for Manufacture and Assembly (DfMA) – has become widely utilised for specific typologies of buildings via working frameworks, i.e. Department for Education and School Buildings. While the DfMA route only addresses the design and construction of a building and not its end of life or reuse possibilities, it relies on the same strategy as DfD does – standardisation – due to the nature of modular construction. While both are in the same family, the fact that the DfMA process has become so commonplace and especially preferable for certain building sectors is favourable for the next logical step – design for deconstruction.
Challenging permanence, procurement & performance
Some circular principles will require the involvement of a demolition contractor very early on in the design process – for example when working with existing buildings – taking the last step of the RIBA Stages and putting it before RIBA Stage 0. Involvement of second-hand material merchants and companies with ‘take-back’ schemes means that there will be new players in the supply chain that are engaged much earlier in the process than the industry is used to.
Client objectives are becoming more and more focused on sustainability, and increasingly circularity is one of these objectives. For the successful implementation of circularity on projects, these client briefs need to capture the extent to which aspirations extend for the whole team to address them.
One of the most important things is to make sure that these sustainability targets are captured in the brief early on and then work towards making them happen and avoid them being value-engineered out. The recent exhibition ‘Long Life, Low Energy: Designing for a Circular Economy’ at the RIBA in London showcased an excellent selection of example projects incorporating a variety of circular principles, including the Manvers Street project in Bath designed by Stride Treglown, which refurbished an existing centrally-located building into a bright and welcoming office space.
Contracts are likely to reflect these shifts in key project figure involvements and move more towards a focus on collaborative procurement types, where the ‘blame culture’ is absent. With deconstruction especially, it will be important to pursue better demolition contracts which provide more incentive for the contractors to be involved in the deconstruction process, and involved early on in the project.
Apart from the usual time/cost/quality priorities, contracts are more likely to move towards the inclusion of other factors becoming more and more important to the clients and incentives, such as for carbon and/or reuse percentages.
Conclusion
Circular economy provides the built environment sector with an opportunity for a wholesale reset of the ways of thinking, designing, building and perceiving the urban grain. The state of the world now increasingly requires every stakeholder to reconsider their role in the value chain, and the actions they can take to address the climate and biodiversity emergencies and consider the planetary boundaries.
Circular principles offer a wide array of actions for stakeholders to take at different stages of a project to develop a built environment asset that is healthier for the users, sensitive to its environmental context, and futureproofed for the next generations.
Ivanova Konstanca is an architect at Stride Treglown