The construction industry must look beyond recycled content to achieve genuine sustainability, writes Steve Hemmings
In the built environment, where our projects have especially long lifespans, it’s easy to lose sight of how materials will be used once buildings are dismantled or demolished.
We have a tendency to rely on recycled content as an indicator of healthy performance for materials management. It’s an approach that, in the short term, prevents waste form going to landfill and reduces immediate resource depletion. It also provides a simple metric for specification. Supplier assessments, for example, position recycled content as a key requirement for meeting project targets. But they rarely ask for details about how materials can be reused or recycled in the future.
That is an unsustainable solution, delaying responsibility for tackling resource depletion until later generations have to confront it, rather than tackling the issue at source.
So what would a closed loop model for construction look like, and how could we get there? To develop a fully sustainable closed loop approach to building, specifiers must start to plan for the end of a building’s life by laying the foundations for the re-use of its materials.
A large amount rests on there being a supply chain in place that is capable of processing materials in an effective and efficient way.
At present, we face a significant obstacle in that buildings are currently demolished and not dismantled in the majority of EU member states. That leads to unsegregated waste going to landfill, and removes the possibility of recovering valuable recyclable materials.
We believe that selective deconstruction can make a massive contribution. It is imperative to make responsible demolition profitable and there are projects afoot in the market to better understand how this can be done.
Since January 2013, Siniat has been working as one of 16 industry partners on a three-year research project, called the Gypsum to Gypsum Project (GtoG), for improving how plasterboard elements can be reclaimed and recycled from buildings at the end of their life.
The project is funded by EU LIFE – the EU’s financial instrument for supporting environmental and nature conservation projects – and the delivery partners include manufacturers, universities, demolition companies - including Cantillon in the UK - and recycling companies.
The project recognises that closed loop recycling depends on three main factors: systematic dismantling of buildings; source sorting of waste to avoid mixed waste and contamination; and stringent specifications for recycled gypsum, so that it can be reincorporated into the manufacturing process. In practice, this involves the full spectrum of the supply chain, which is why the project’s membership is so broad.
Ultimately, the industry will need to take a holistic approach to deconstruction. But plasterboard is an important place to start. Its principal material, gypsum, is infinitely recyclable as gypsum, and unlocking the potential to keep this material within a closed cycle should provide valuable insight for other parts of the industry.
Equally crucial is to involve the entire supply chain. Marshalling materials in our sector is a long-term task, and a shift in mindset and a maturing marketplace for post-consumer waste should make sustainable practice a more attractive option in construction.
- More on the Gypsum to Gypsum project can be found at: www.gypsumtogypsum.org
Steve Hemmings is head of environment, health and safety (EHS) and sustainability at plasterboard manufacturer Siniat.