Charlie Law, an ambassador for the upcoming RWM in Partnership with CIWM event, and founder and managing director of Sustainable Construction Solutions, looks at the circular economy in the construction sector and what is needed to make it work
In volume terms, construction and demolition are among the biggest sources of all waste generated in the European Union, equating to 25-30%. This consists of numerous materials, including concrete, bricks, gypsum, wood, glass, metals, plastic, and excavated soil, many of which are already recycled or re-used to various degrees across the EU, but could we do more?
In a circular economy the value of products and materials is maintained for as long as possible; waste and resource use are minimised, and resources are kept within the economy when a product has reached the end of its life, to be used again and again to create further value. This is a move away from the linear model of economic growth we relied on in the past, based on a ‘take-make-dispose’ model.
To facilitate the move to a more circular economy, in December 2015 the European Commission put forward a Circular Economy Package, which includes revised legislative proposals on waste to enable industries to become more efficient with resources. Construction and demolition waste was one of the key areas addressed, to help meet the existing EU-wide mandatory target of re-using or recycling a minimum of 70% (by weight) of non-hazardous construction and demolition waste (excluding soils) by 2020. Next steps will be for the European Parliament and Council to prioritise adoption and implementation of the legislative proposals.
Measures Affecting The Construction Industry
The package includes a comprehensive Action Plan to address all phases in the lifecycle of a product: from production and consumption to waste management and the market for secondary raw materials. The action plan also includes a number of steps that will target market barriers in specific sectors or material streams, including critical raw materials and construction and demolition. For example it states ‘valuable materials are not always identified, collected separately, or adequately recovered. The Commission will develop targeted guidelines for use on demolition sites for that purpose,’ which could imply that pre-redevelopment audits will be required, as well as the promotion of sorting systems and voluntary recycling protocols, which could see the relaunch of resource management plans? It also promotes the efficient use of bio-based products, such as timber, to ensure the best value is realised through cascading uses through their lifecycle. This could mean promoting the use of more timber in construction, such as a ‘wood first’ policy?
Another key area the EU has recognised in the new package is that it is essential to encourage design improvements that will increase the durability, recyclability and reusability of components within buildings. It will therefore develop indicators to assess environmental performance throughout the lifecycle of a building, and promote their use for building projects through large demonstration projects and guidance (Closing the Loop: An EU Action Plan for the Circular Economy, December 2015).
Despite its potential, the industry has been slow to adopt circular economy principles on construction projects, partly because it is perceived to be too difficult to achieve. The right regulatory framework combined with measures to make implementation clearer and simpler should help contractors, manufacturers, designers and clients’ transition towards a circular economy.
With ever increasing pressure on global resources, we need to look at how we can recover more value from construction materials in the waste stream, or better still not let them become waste in the first place.
Changing The Way We Build
There are a number of circular products readily available, but a more holistic approach is required, taking the whole building as one and understanding how the numerous components interact and co-exist with each other over time.
So how should we do this? Greater collaboration between designers, contractors and manufacturers is a key step. Manufacturers will be the main drivers of change as they are recognising that, by re-using, remanufacturing and recycling components, they will benefit from lower raw material cost and improved resource security.
What we need is more product manufacturers looking at these circular economy solutions, such as fixings that allow their products to be disassembled and reused at the end of their service life, and designers need to look at how they incorporate components into the building so they can be easily recovered.
Take, for example, the humble brick. These are normally laid in cement mortar which binds everything together and is very difficult to remove at end of life without damaging the brick. If we designed for deconstruction, we may go back to laying bricks in lime mortar, which is easily removed; and is why there is a good salvage market for bricks from older buildings. Laying bricks on lime mortar does take a bit longer, but due to changes in building methods, this brickwork may not be load-bearing and is therefore rarely on the critical path of the construction programme.
Adopting New Business Models
Although take back schemes do exist, at present there is little incentive for the manufacturer to collect their product at end of life. Many construction materials are of relatively low value, and may be costly or impractical to recover.
If the product manufacturer retained ownership of the products, and the logistics solutions were put in place to allow economical recovery, there would be greater incentive to recover the materials and/or components from them at the end of their service life. This would reduce their reliance on virgin raw materials and improve material security, and subsequent financial security, by avoiding the fluctuations in commodity prices.
However, it will require a number of factors to come together for the whole system to work. Contractors need to be ready to deliver new business models, working closely with manufacturers to make the required changes. The design community will need to incorporate circular products within their designs in the right way, to allow for easy recovery. And most importantly, the client needs to be willing to accept these changes, and start asking ‘how circular is my building?’
