Heidelberg Materials UK Helps Deliver Low-Carbon London Road Scheme

Norfolk road project uses 90% recycled materials in major resurfacing scheme

A resurfacing project on the A47 in Norfolk has demonstrated how road maintenance can cut carbon emissions while using recycled materials at scale. Heidelberg Materials UK says the scheme between Acle and Great Yarmouth used more than 13,500 tonnes of recycled content to create a new structural road layer. The company projects the approach will save over 400 tonnes of CO₂ compared with conventional methods.

National Highways commissioned the work as part of a deliberate effort to reduce the carbon footprint of road maintenance. The project ran overnight between May and November 2025. It required coordination between Heidelberg Materials UK, engineering consultancy WSP, and National Highways to deliver a lower-carbon outcome without compromising road performance.

The significance lies in the combination of techniques used. Recycled materials made up more than 90% of the new road layer. A nearby recycling plant reduced transport emissions. Electric machinery replaced diesel equipment where possible. Furthermore, the project diverted 2,400 tonnes of tar-bound material from specialist landfill by processing it on site.

Road maintenance traditionally relies on virgin aggregate and energy-intensive hot-mix asphalt. This project shows an alternative approach that reduces both material extraction and carbon emissions while meeting the structural requirements of a busy trunk road.

Foamed asphalt technology cuts energy demand for road surfacing

The project used evoBuild foamed asphalt instead of conventional hot-mix asphalt for the structural layer. This material requires significantly less energy to produce because it operates at lower temperatures. Consequently, carbon emissions from the manufacturing process fall compared with traditional methods.

Foamed asphalt also accepts higher levels of recycled content than hot-mix alternatives. The technology works by injecting water and air into bitumen under controlled conditions. This creates a foam that coats aggregate particles at temperatures around 100°C lower than hot-mix asphalt. The result is a material that performs structurally while using less energy.

Heidelberg Materials UK positioned this technology as central to achieving the high recycled content in the project. The company reports that the material exceeded 90% recycled aggregate in the finished road layer. This level of recycled content is unusual in structural applications where performance requirements are demanding.

The energy saving from lower production temperatures directly reduces Scope 1 and Scope 2 emissions. For contractors and clients tracking embodied carbon in infrastructure projects, this represents a material difference. Moreover, the technology allows tar-bound materials to be recycled rather than sent to specialist disposal facilities.

Proximity of recycling plant and asphalt supply reduces transport emissions

Heidelberg Materials UK operated a cold-mix recycling plant eight miles from the site. The company says this proximity reduced transport emissions compared with sourcing virgin materials from more distant quarries. Additionally, the asphalt supply plant was 16 miles closer than alternative suppliers.

Transport represents a significant proportion of carbon emissions in construction projects. Shorter haulage distances mean fewer vehicle movements and lower diesel consumption. For a project using more than 13,500 tonnes of recycled materials, the cumulative effect of reduced journey lengths becomes substantial.

The recycling plant processed existing road material removed from the A47 during resurfacing. This created a closed-loop system where waste from the project became feedstock for the new road layer. Consequently, the need for virgin aggregate extraction fell alongside transport requirements.

Processing tar-bound material on site also eliminated the need to transport 2,400 tonnes of hazardous waste to specialist landfill facilities. This material contains coal tar, which requires careful handling and disposal. By recycling it instead, the project avoided both transport emissions and landfill costs.

The location of processing facilities relative to construction sites will increasingly influence project carbon footprints. For contractors bidding on public sector work, the ability to demonstrate local supply chains and recycling infrastructure may become a competitive advantage.

Project details and carbon savings from Norfolk resurfacing work

The A47 scheme delivered measurable environmental outcomes through specific technical choices. These facts provide a baseline for comparing similar projects:

• The project took place on the A47 between Acle and Great Yarmouth in Norfolk, a busy trunk road connecting the East of England.
• Work ran overnight between May and November 2025 to minimize disruption to traffic on this key route.
• More than 400 tonnes of CO₂ emissions were avoided compared with conventional resurfacing using virgin materials and hot-mix asphalt.
• Over 13,500 tonnes of recycled materials were incorporated into the new road layer, demonstrating that high recycled content is achievable in structural applications.
• Approximately 2,400 tonnes of tar-bound material were diverted from specialist landfill and processed for reuse in the road structure.
• The cold-mix recycling plant was located eight miles from site, while the asphalt supply plant was 16 miles closer than alternative sources.
• Electric machinery replaced diesel equipment where operationally feasible, further reducing direct emissions from construction activity.

Implications for infrastructure maintenance and public sector procurement

This project matters because it demonstrates that road maintenance can achieve substantial carbon reductions without experimental technology. The methods used are proven and commercially available. National Highways explicitly asked for a low-carbon approach, showing that client requirements are driving change in infrastructure delivery.

Public sector clients increasingly include carbon reduction requirements in tender specifications. Procurement Policy Note 06/21 requires suppliers bidding for central government contracts above £5 million to demonstrate their approach to net zero. As a result, contractors need to show they can deliver lower-carbon outcomes on major projects.

The Norfolk scheme provides evidence that recycled content can exceed 90% in structural applications. This counters the perception that recycled materials are only suitable for lower-specification work. For clients setting embodied carbon targets, it establishes a benchmark for what is achievable in road maintenance.

Transport emissions from material haulage represent a controllable variable in project carbon footprints. Contractors with local recycling infrastructure can reduce these emissions significantly. Therefore, the business case for regional recycling plants strengthens as carbon reduction becomes a procurement criterion.

Processing tar-bound material on site rather than sending it to landfill creates both environmental and cost benefits. Specialist landfill for hazardous waste is expensive. Recycling this material in place reduces disposal costs while avoiding associated transport emissions. Consequently, the circular approach delivers commercial as well as environmental advantages.

For manufacturers supplying the construction sector, the project highlights demand for lower-carbon products like foamed asphalt. Companies developing materials that enable higher recycled content or reduce production energy may find growing markets as infrastructure clients tighten carbon requirements.

Road maintenance sector faces pressure to reduce embodied carbon

The construction and maintenance of road infrastructure contributes materially to UK carbon emissions. Material extraction, processing, and transport all generate emissions before construction work begins. As a result, clients and regulators are focusing attention on embodied carbon in addition to operational emissions.

National Highways manages England’s strategic road network. The organization has committed to achieving net zero emissions by 2050. This target includes carbon from construction and maintenance activities, not just vehicle emissions from traffic. Consequently, projects like the A47 resurfacing reflect a broader shift in how infrastructure is specified and delivered.

The use of virgin aggregate has come under particular scrutiny. Quarrying, crushing, and transporting aggregate generates emissions and depletes finite resources. Recycling existing road materials reduces both impacts. However, technical standards and performance requirements have historically limited recycled content in structural applications.

This project shows those barriers can be overcome. The combination of foamed asphalt technology and processed recycled aggregate delivered a road layer that meets structural requirements while using minimal virgin material. For the wider sector, this establishes technical precedent.

Small and medium contractors working on local authority or Highways England projects will increasingly face similar requirements. Understanding how to source recycled materials, work with local recycling plants, and calculate embodied carbon will become standard skills. Businesses that develop this capability early may gain competitive advantage in procurement processes.

The financial case for lower-carbon methods depends partly on carbon pricing and regulation. As carbon costs rise through mechanisms like carbon border adjustment or internal carbon pricing by clients, the economic gap between conventional and lower-carbon methods narrows. Projects that appear costlier today may become cost-competitive as policy evolves.

Circular economy principles applied to highway maintenance operations

Heidelberg Materials UK described the project as a practical example of circular economy principles in infrastructure. The term describes economic systems designed to eliminate waste by keeping materials in use. In this case, road material removed during resurfacing became feedstock for the new road layer.

The circular approach contrasts with the traditional linear model where virgin materials are extracted, used once, and then disposed of. By processing existing materials on site, the project reduced demand for new aggregate extraction. It also avoided sending tar-bound material to landfill. Therefore, resource efficiency improved at both ends of the material lifecycle.

For businesses, circular economy thinking creates opportunities to reduce costs and secure supply. Materials that were previously waste can become valuable inputs. Local processing reduces transport costs. However, implementing circular systems requires investment in processing capability and changes to established procurement practices.

The construction sector has been slower than some industries to adopt circular principles. Technical standards, insurance requirements, and procurement habits have favored virgin materials. Projects like the Norfolk resurfacing demonstrate that circular approaches can meet demanding performance standards when properly implemented.

Supply chain transparency becomes more important in circular systems. Clients need confidence that recycled materials meet specifications and perform as required. Consequently, testing, certification, and traceability assume greater significance. Contractors and suppliers that can provide this assurance will be better positioned as circular requirements spread.

The financial benefits of circularity in construction depend on local circumstances. Where landfill costs are high and recycling infrastructure exists nearby, the case strengthens. Where virgin materials are cheap and disposal costs low, economic incentives are weaker. However, regulatory pressure and client requirements may drive change regardless of immediate cost considerations.

Further information on infrastructure carbon reduction and material standards

National Highways publishes guidance on sustainable construction and carbon reduction for contractors working on the strategic road network. This includes specifications for recycled materials in road construction. The organization’s net zero plan sets out targets and priorities for reducing emissions across its operations.

The Department for Transport provides policy direction on decarbonizing infrastructure. This includes carbon reduction in construction and maintenance activities. Government guidance on Procurement Policy Note 06/21 explains requirements for suppliers bidding on major public contracts.

The Institution of Civil Engineers maintains resources on embodied carbon in infrastructure and circular economy principles in construction. These provide technical context for professionals implementing lower-carbon approaches in highway projects.

Businesses seeking to reduce carbon in their construction supply chains can find support through sustainable procurement guidance for infrastructure projects. Understanding how to calculate and report embodied carbon is also covered in carbon reporting compliance support for contractors and suppliers.