After water, concrete is the most widely used material on earth. Favoured by engineers since Roman times, today roughly 30 billion tonnes of concrete are poured around the world each year—around three times as many per capita compared to 1980.
We need concrete. It remains vital for building infrastructure to raise global living standards but is alone responsible for around 5-7% of global carbon emissions, roughly the same as the total emissions from Africa and South America combined.
The scale of the challenge means that a fast-paced, targeted innovation drive is needed to reduce demand for new concrete by reusing buildings and utilising more recycled materials. In situations where using new concrete is unavoidable, we need to reduce emissions across the supply chain from mining, transport and processing, and through efficient design and construction.
The innovation is out there. We are seeing more of it—for example the impressive Boston Barrier Scheme here in the UK. And it has the potential to help concrete become carbon-neutral, or even negative by capturing industrial emissions as a feedstock for concrete production.
But this innovation needs a deadline.
A clear timetable for reducing emissions will galvanise new collaborative efforts, especially if blended with incentives that encourage the construction industry to change practices and adopt new technologies across a wide range of projects, from affordable housing to major infrastructure.
A clear timetable for reducing emissions will galvanise new collaborative efforts.
By 2030, these should include incentives for recycling concrete materials and reusing buildings over demolition. For example by removing VAT from refurbishment so there is a level playing field with new build where VAT is not paid at present. And the use of intelligent infrastructure procurement to drive either this reuse and recycling, or the usage of low-carbon concrete. Finally, we need to see a blend of government investment and commercial incentives to create carbon capture pilots at cement works.
These are the first steps. But the deadline gives us the destination, and is the lynchpin in these efforts.
Similar time-bound approaches have been used successfully to phase out energy-intensive lightbulbs, and to set an endpoint on combustion engines. But concrete so far remains a missed opportunity. This is despite a recent report by the Institution of Civil Engineers projecting that the UK’s concrete-related carbon emissions could halve by 2035.
By providing key deadlines along the pathway to decarbonised concrete, we can drive engineering-led innovation in the UK, with knock-on benefits for the built environment worldwide. While at the same time giving the construction industry the right balance of time and impetus to drive the changes we need to see.