Materials reuse must become business as usual to realise circular economy

Have deconstruction practices and materials reuse made headway in the construction industry? A recent webinar saw an expert panel discuss the strategies needed to advance the circular economy in construction, and examples of outstanding deconstruction and reuse projects.

The construction industry is increasingly aware of the need for – and value of – reusing construction materials at the end of the building life cycle, with disassembly having increased in recent years and demand for more reuse hubs to be established.

Yet if construction is to establish a fully circular economy there must be a change of culture, with more collaboration, information and regulation to encourage alternative approaches. At a recent WBEF webinar, professionals involved in the field discussed some of these challenges – and how they could be overcome.

Buildings should be thought of as materials banks

Materials reuse in construction has certainly increased over the past five years, says Alliance for Sustainable Building Products (ASBP) technical director Dr Katherine Adams, who is also co-founder and director of sustainability consultancy Reusefully. Some products and materials are a lot easier to reuse and there are well-defined processes for doing so, whereas others are more difficult, she explains.

A lot of buildings use quite low-quality materials, which offer little value at the end of the life cycle. ‘This underscores the need to consider what gets designed into future buildings, how we can retain the value in those elements and why we need to start to think of buildings as material banks with residual value,’ she says.

It is important to understand where the value for materials reuse comes from, says the John F. Hunt Group’s head of sustainability Daniel Sweeney. Sometimes there’s an inherent value in the materials. In these instances, the industry has leeway to create a third-party remanufacture rout (involving bringing end-of-life products back to like-new condition for resale with the same warranty as a new product would have).  Reuse is also possible when there is no inherent value but a potential carbon reduction benefit, planning or funding requirement, or rent premium from occupiers, he says.

Establishing more hubs can promote collaboration and reuse

For some more commonly reused products such as steel and raised access flooring, there are processes in place (such as the Steel Construction Institute’s Protocol for Reusing Structural Steel) that enable the provision of insurance and warranties. However, there is still work to be done around insurance of reused materials in general, explains ASBP director of circular economy and reuse Debbie Ward.

As part of its work on materials reuse under the Reuse Now campaign, ASBP has been mapping out the route for building elements that are harder to reuse, such as glass partitions. Working closely with insurers and manufacturers to determine how to address insurance and warranties is going to be key to ensure the reuse of these elements, says Debbie.

She continues that there are only a handful of materials reuse hub in the UK at the moment, including the Rebuild Site in Carlisle. However, she notes that there is growing appetite for such hubs in various different cities, particularly in London. Giving people access to cheaper materials enables more resilient local communities, she says.

Hubs are also being considered alongside big developments, Debbie observes, as these can produce a lot of surplus materials that haven’t been used at all and which would be categorised as waste if reuse were not an option. Alongside the infrastructure needed to deal with this surplus, businesses and individuals need to consider whether new products and materials are always required, she says. ASBP CEO Simon Corbey MRICS agrees, concluding: ‘We really need a reuse hub every 30 to 50 miles.’

Most of the panel acknowledge that materials reuse is technically feasible, Debbie resumes. The challenge is that it is not quite financially viable in a lot of instances. Materials reuse needs to become business as usual: a low-risk, familiar part of the building life cycle that people have the skills and experience to manage.

Regulations push manufacturers to take more responsibility

Henry Robinson is ecosystem development director at research centre the Francis Crick Institute and director of developer Ampersand. He explains that in the UK, local authorities such as the City of Westminster are starting to refuse planning permission for proposed developments where they have poor circular economy statements. This ‘brings consideration of the circular economy to the centre of the planning application,’ he maintains.

Daniel agrees, adding: ‘The challenge is that the incentives for reuse don’t always align. Often the value or benefit may go to the users of the materials coming out of your project, when it is the client on your current project who is paying for the disassembly. This makes having those open and honest conversations with clients to identify the sources of value even more important.’

The manufacturing industry is starting to understand that the circular economy and reuse is critical, says Simon. However, lots of manufacturers still have a vested interest in selling new products, Katherine responds. Developing the business models to sell more reclaimed materials is quite a big ask for some that have invested heavily in manufacturing new.

She continues that new regulations such as the EU’s Digital Product Passports nevertheless require disclosure on circularity and reuse. Coupled with an increased number of industry stakeholders asking about product take-back schemes, she expects that more manufacturers will start to consider how they can adapt.

Alongside this, adds Debbie, extended producer responsibilities are another way of encouraging manufacturers to take more responsibility for what happens to their products at buildings’ end of life. The regulation of construction products required under the UK Building Safety Act 2022 will also prompt changes, she says.

Better data retention about products needed to inform repurposing

The panel identified a lack of time and information as two of the biggest barriers to upscaling materials reuse on deconstruction projects. Katherine explains: ‘ At Reusefully, we’ll rarely have a lot of information on the buildings as we are going in to assess them. Sometimes you don’t get floor-plans or an operation or maintenance manual. And the less you know about a product, the riskier it is to reuse it.

‘It’s good practice to have detailed information on your buildings and the materials in them. This is so that at deconstruction phase, you don’t have to make lots of assumptions about the product in terms of how old it is, who the manufacturer is and whether it has a warranty, for example.’

Having more benchmarking data would be very helpful, continues Katherine. At the moment, Reusefully sees widely divergent calculations for the costs of deconstruction and reuse on projects. Sometimes this may be because contractors do not want to take on materials reclamation as they aren’t confident about how long it might take. As a result, they add a lot of risk to their estimate and price the work especially high, she explains.

Project schedules must allow time for considering materials reuse

Allowing enough time on a project for deconstruction and reuse is essential, explains Henry. Starting early in the process and looking at what parts of a building can sensibly be reused or repositioned for future use is important as well, he says. ‘We have to be realistic about what the circular economy means from a programme point of view. Incorporating it into redevelopment or deconstruction projects will make the programme longer and need to be reflected in your appraisal. But as a client, having that certainty on project priorities is essential to communicate from day one,’ he continues.

Daniel agrees that time can be substantial barrier to better materials reuse. ‘I understand there’s a reason for not always wanting early collaboration on a project, keeping that competitive tension in the supply chain so you can get the best value. However, when you appoint contractors quite late on, the project start date is then very soon after.

‘As soon as you start on site, your programme becomes further compressed by soft strip demolition and then any demolition phases. The next thing you know, there’s the main contractor wanting to move the project forward, so the window of opportunity to reclaim materials becomes smaller and smaller.

‘Without early engagement for deconstruction planning on a project, you are narrowing your window. And when you don’t have time to collect information about the building to consider what materials can be reclaimed and how to extract them, that’s a further barrier to materials reuse.’

Clear strategies help projects reduce embodied carbon in practice

The panel mentioned several examples of success in deconstruction and materials reuse, many of them in London.

On the 180 Picadilly project, Daniel explains, the reuse strategy was set out quite clearly, with a clear schedule of items that were to be retained. In the end, around 2,000 individual items were sent for reuse, down to the toilets, plugs, lights and even small-scale furniture, fixtures and fittings.

Daniel describes working with British Land on the Euston Tower, where just a single item – albeit a 4.5m by 1.5m concrete slab – was removed and reused in the development as a block-and-beam slab, contributing to the project’s plan to reduce embodied carbon.

Henry mentions a project at 50 Baker Street where the concrete from an existing building was sliced up and used as void formers in the new foundation, saving a huge amount of embodied carbon as well. At the Frances Crick Institute, he also worked with Reef to create Tribeca bricks from the clay excavated from the site, which formed the walls for the basement.

Schiphol Bus Station in the Netherlands is another great example, explains Katherine. It started off as a Second World War aircraft hangar, which was then bought and used as a hangar at Schiphol Airport. Following that, it was repurposed again as a hangar for the Dutch Ministry of Justice, and in its most recent iteration it became a bus shelter. It is a great reflection of the long life that buildings and materials can have, says Katherine.

She also mentions that LSE and John F. Hunt are working on 35 Lincoln’s Inn Fields, where LSE set a 50% reuse target. This includes the reuse of brickwork and turning crushed bricks into dust for a lime plaster and terrazzo. Debbie adds that the Arup and British Land scheme at 1 Triton Square reused the facade with the help of a pop-up factory a few miles away that helped to repurpose it.

Deconstruction plays a key role in achieving circularity by enabling the reuse and recycling of materials and components at the end of a building’s life cycle.

This approach minimises landfill waste and significantly reduces embodied carbon, doing which are essential pillars of circularity. It is estimated that construction and demolition waste accounts for nearly one-third of solid waste generated, making deconstruction and disassembly critical for sustainable building practices.