The construction sector consumes about 40% of the produced energy and natural resources, produces more than 40% of all carbon emissions and generates about 30% of the total solid waste. In the UK, approximately 7 000 tonnes of construction and demolition solid waste are generated every hour. The take-make-waste approach found in a linear economy model is no longer acceptable. A circular model is required to save energy, carbon and avoid waste generation, where components or entire buildings are retained, repurposed or recovered for future use. The next best alternative to reuse is recycling, although energy and carbon are required to manufacture the new components.
The reuse practice in the construction sector still faces significant barriers, mainly concerning procurement and lack of supply chain business models. Although the industry is currently attracted to exploring the use of reclaimed components, the design community could do more to enable such a practice.
An existing building flagged for demolition is commonly neglected if incompatible with the new development, the efforts being directed towards a more suitable built environment focused primarily on the new development strategy. However, existing buildings and infrastructure may be a source of valuable materials that can be salvaged (such as steel, bricks, precast elements, etc.) and reused in the same or new development by the project team or by others.
Market specialist stockists have been pioneering the recovery of existing components, driven by sustainability benefits but also because the model can be profitable. Considering the high demand for low-carbon products, the value of salvaged components will likely increase in the short to medium term. However, the lack of communication with the demolition contractors hinders the recovery. The amount of salvaged components suitable for reuse is currently limited since most buildings are demolished without any recovery targets and recommendations. Increasing the amount of salvaged components in good condition is key to facilitating procurement and market adoption of the reuse practice and circular economy.
Considering that most of the embodied carbon of a building is associated with the structure, structural engineers have an important responsibility. On the other hand, most of the waste generated by demolition relates to the structure, making the structural engineers important advisors on the materials arising from demolition and opportunities for reclamation and repurposing.
A pre-demolition audit (PDA) aims to inform the building owner and other relevant project actors of the materials and components arising from the demolition or deconstruction process and guide on appropriate end-of-life scenarios. By providing a list and quantities of existing components, reclamation opportunities and supply chain actors capable of enabling their recovery, the audit is crucial in empowering the circular economy model in the building environment.
Pre-demolition/deconstruction audit workflow
The design team is engaged in early project states at which the carbon reduction and design/construction efficiency initiatives have more potential. The same principles apply to the existing building since the completion of a pre-demolition/deconstruction audit at an early project stage can enable appropriate business models and allow high recovery rates for the existing components. As such, the engineer has a key role in supporting the PDA exercise and highlighting the benefits of the audit to the new development actors and the broader built environment. Pell Frischmann has been pioneering the completion of PDAs with sound structural engineering input.
We support that all project actors are responsible for facilitating the creation of stocks of reclaimed materials suitable to be used in new developments. Wishing to specify reclaimed components alone is not enough. We have been exploring approaches and solutions to salvage and repurpose existing components through innovation, research programmes, platforms, and specialist stockists’ advice. Our end-of-life management recommendations for each material are tailored to comply with project-specific targets, aiming for the inclusion of guidance in the demolition specifications and enabling communication within the supply chain and a feasible market model. Pell Frischmann is committed to encouraging the completion of PDAs to enable the circular economy model in the construction sector. Our approach is based on an early engagement of key supply chain actors from our network and is highly driven by innovation.
We have completed several PDAs, helping our clients, such as Landsec and Regal London, seek planning permission and reach challenging sustainability aspirations. Get in touch with us to find out how we can help you make your practice more sustainable.