Sustainable road construction and maintenance

Asphalt is one of the most sustainable construction materials available due to its durability and the fact that it is 100% recyclable: worn out surfaces can be reused back into new asphalt, which can also contain other recycled content as well as secondary materials.

We work with our customers to help meet their carbon reduction and air quality targets by using innovative asphalt solutions suitable for all road construction and maintenance schemes, which fall into three, interlinking categories.

Download our road to net zero asphalt brochure

Lower carbon asphalts

Recycled content

Emissions reduction

Lower carbon solutions

Around half of the carbon emissions associated with asphalt production and laying come from the fuel used in manufacture, so reducing the temperature at which asphalt is produced is key. But using long-life products to increase the durability of the asphalt is also important as this reduces the number of maintenance interventions, supporting the circular economy and reducing emissions.

Heidelberg Materials UK has developed a number of innovative asphalt solutions that can help reduce the carbon footprint of road construction and maintenance schemes, all of which can be produced using its ERA warm mix process, which cuts CO₂ emissions by up to 15%.

Read about some of our solutions

A414 upgrade in Hertfordshire

The A414 upgrade in Hertfordshire showcases a range of our innovative, durable, lower carbon asphalt solutions to help National Highways meet its net zero carbon ambitions.

ERA warm mix asphalt (WMA)

The use of warm mix asphalts (WMAs) cut CO₂ emissions by around 15% and, importantly, can be used to produce a number of different products with recycled or secondary content as well as those that offer increased durability, enhancing these savings.

While hot mix asphalt, produced at temperatures in excess of 160°C, is currently the default asphalt type specified in the UK, this is changing with National Highways now encouraging the use of WMAs as standard on the strategic road network.

Our ERA warm mix process can be used to produce a wide range of asphalts and offers a number of additional benefits including:

Faster setting times
Increased durability through reduced oxidation
Reduced steam production in wet weather
Reduced odour on site
Improves adhesion as both liquid antistrip and warm mix additive
Less fumes: a 10°C reduction in mix temperature reduces fuming by ~50%

Warm mix asphalt, Dorset Highways Strategic Partnership Project case study

View case study

Reducing carbon emissions and improving efficiencies, National Highways Areas 6 & 8 Project case study

View case study

CarbonLock (biogenic asphalt)

CarbonLock includes biogenic material that absorbs and ‘locks in’ CO2 throughout its life, even when it is recycled. It is also produced using our ERA warm mix process, which allows the asphalt to be manufactured at a lower temperature. As a result, the product provides at least a 25% reduction in carbon emissions compared with standard hot mix.

The low void, high bitumen content of the asphalt, coupled with the lower production temperatures, also creates a very durable material – one which can also be laid as a single layer product, increasing efficiency and reducing disruption for road users.

Technical data sheet

Reduced emissions asphalt using ERA warm mix technology

Our new CarbonLock biogenic asphalt has been used in Dorset to reduce whole-life carbon emissions and enhance durability of the new road surface.

Duralayer bio trial with Dorset Council

AgeLast (Enhancing durability)

AgeLast asphalts contain an additive that reduces the rate of bitumen ageing to delay the onset of embrittlement and prolong the life of asphalt surfacing, reducing the need for intervention and associated carbon emissions. They are produced using our ERA warm mix process, reducing the CO₂ emissions associated with production, compared with traditional hot mix asphalt.

Technical data sheet

Recycled content

Recycled asphalt planings (RAP)

Asphalt is 100% recyclable at its end of life and can be incorporated back into new asphalt. Using these recycled asphalt planings (RAP) in the asphalt production process avoids using virgin aggregates, protecting natural resources for future generations. It also reduces the use of bitumen, supporting the circular economy and reducing carbon emissions.

A338 Bournemouth Spur Road, Dorset

All of the old road materials were incorporated into the reconstruction of the A338 in Bournemouth, Dorset

Read case study

RecyclePlast

Our RecyclePlast asphalt contains additives derived from waste plastics, produced at lower temperatures using our ERA warm mix process.

The chemically modified waste plastic is compatible with bitumen without compromising performance and provides a beneficial use for plastic at the end of its life rather than it going to landfill. RecyclePlast can also be recycled back into new asphalt at the end of its life.

Technical data sheet

Use of innovative warm mix asphalt

Check out Hanson UK's use of an innovative warm mix asphalt containing chemically treated waste plastic with Cumbria Council and Shell Construction and Road. It is one example of the new low carbon products we are developing and testing as part of our decarbonisation journey.

Trial of additives derived from waste plastic in highways surfacing, Penrith and Nenthead, Cumbria

Cumbria’s project is aimed at reducing the carbon footprint of highways schemes and providing a more resilient road network.

View case study

Emissions reduction

Air quality is an issue that impacts people across the globe, particularly in cities. To minimise the impact on air quality when producing and laying asphalt – and not exacerbate air quality issues – we offer our customers a range of CleanAir reduced emission asphalt products.

CleanAir (Reduced emissions asphalt REA)

CleanAir helps to minimise the impact of asphalt production and laying on local air quality by reducing specific gases and particulate matter from asphalt mixtures, which is particularly beneficial for ultra-low emission zones.

It contains a specialist binder, which has been shown to reduce specific gases and particulate matter from asphalt mixes by an average of 40% compared to conventional bitumen and can be used in all of our asphalt products.

Technical data sheet

Reduced emissions asphalt using ERA warm mix technology

We helped Tesco meets its sustainability targets while resurfacing its customer car parks by using CleanAir, produced using our ERA warm mix technology, to minimise the impact of the asphalt on local air quality.

Foamed asphalt

Foamed asphalt is a cold mix asphalt containing up to 95% recycled materials, reclaimed fillers/additives, bitumen, cement, and water. It can reduce the carbon emissions associated with asphalt production and laying by a minimum of 40% compared with conventional hot mix materials.

The product is manufactured by injecting water and air into hot bitumen under high pressure, which causes the bitumen to foam, increasing its volume and decreasing its viscosity. This allows the effective coating of aggregate.

Learn more