A residential road improvement project in the London Borough of Redbridge has achieved carbon savings of more than 75 tonnes after contractors combined lower carbon concrete, recycled asphalt and warm mix surfacing technologies on a local highways scheme.
The project, delivered by Heidelberg Materials UK and contractor Kenson Highways, involved resurfacing and flood mitigation works on Heathcote Avenue in Clayhall.
According to project partners, the largest carbon reduction came from the use of Heidelberg Materials’ evoZero carbon captured near-zero cement, which accounted for more than 35% of the total emissions savings on the scheme.
Lower carbon concrete and recycled asphalt used across scheme
The evoZero cement was used in lower carbon concrete supplied for kerb and edging haunching works, as well as within the footway sub-base.
The project also incorporated recycled and lower temperature asphalt technologies aimed at reducing embodied carbon across the resurfacing package.
A total of 275 tonnes of asphalt binder course material was laid containing 25% reclaimed asphalt (RA) and 6.5% ACLA additive.
Meanwhile, 248 tonnes of asphalt surface course included Heidelberg Materials’ CarbonLock bio-binder and was produced using the company’s Era 140 warm mix asphalt process.
The CarbonLock binder uses biogenic materials designed to absorb and store CO₂, while the warm mix asphalt production process reduces manufacturing temperatures by up to 40°C compared with conventional hot mix asphalt.
According to Heidelberg Materials, the process can reduce production-related CO₂ emissions by up to 15%.
Recycled footway surfacing trialled for first time in Redbridge
The scheme also marked the first time a footway mix containing 25% reclaimed asphalt had been trialled in Redbridge.
In addition to resurfacing works, the project included flood mitigation measures as part of wider efforts to improve resilience and drainage performance on the residential road.
James Moorhouse, Regional Director for Concrete at Heidelberg Materials UK, said: “The use of evoZero carbon-captured near-zero cement was vital in helping to minimise the carbon impact of the improvement project.
“We worked closely with Kenson Highways to ensure all the materials used performed correctly while also delivering the desired carbon benefits. The project is a great example of supply chain collaboration to meet the client’s objectives.”
David Shelley, Director at Kenson Highways, added: “Our aim on this scheme was to achieve the best possible carbon reduction.
“Initial calculations indicate that we saved over 75 tonnes of carbon overall, with the greatest single saving coming from the use of evoZero cement, which accounted for more than 35 per cent of the total.
“Without the support and expertise of Heidelberg Materials’ technical teams, and the introduction of these innovative low-carbon products, we would not have been able to achieve anything close to this level of saving.”
