The residual unavoidable carbon emissions were then offset using high-quality Verified Carbon Standard (VCS) units, administered and certified by Verra, the world’s largest carbon registry, to make it a one-of-a-kind carbon neutral scheme.

 

Approximately 280 tonnes of warm mix asphalt was laid as a single layer, covering 1,600m2 of carriageway. The proprietary mix, designed, manufactured, and laid by FM Conway, was the combination of three specifications of the contractor’s 14mm SureLayer E product with the addition of extra recycled aggregate.

 

The finished product provided a brand new surface course containing 92% recycled materials, which delivered other benefits in addition to carbon reduction, such as faster installation and less neighbourhood disruption. The material’s use of a bespoke polymer modified bitumen also meant increased durability and resilience, extending its life for years to come.

 

To achieve the substantial carbon savings, the asphalt material was manufactured at lower temperatures and laid in a thinner layer, meaning there were approximately 30% less tonnes manufactured, transported and laid – saving carbon throughout the life cycle.

 

The use of recycled content meant less virgin bitumen and less quarried stone was used, preserving the natural environment and reducing the carbon impact from haulage of these materials. In addition, the road planings were transported back to the same plant where the asphalt was made, optimising HGV logistics and minimising empty journeys.

 

Alongside the new carriageway, the scheme also involved the enhancement of the footway between the Woodfield Medical Centre and Harrow Road, as well as the installation of 11 new LED lamp columns, 200m of new cabling, and a full drainage review and clean.

 

 

Additional carbon savings were made in the footway construction, through the implementation of FM Conway’s low carbon model, which incorporated closed loop recycling of excavated materials, as well as the use of lower thickness paving materials and lower carbon cement alternatives.

 

The full scope of works was carried out using no fossil fuels on site. This was achieved through the use of Hydrotreated Vegetable Oil (HVO) in the resurfacing element of the scheme, plus the use of electric mini-excavators, disc cutters and compaction plates, as well as using a solar powered welfare unit which used HVO as a backup in the footways element.

 

After the industry-leading embodied and operational carbon savings were achieved, the residual unavoidable emissions were offset using high-quality carbon removal and renewable power projects. The business has also supported tree planting in the UK, through the purchase of Pending Issuance Units administered by the Woodland Carbon Code, marking FM Conway’s investment in future UK-based carbon removals.

 

The completed project now joins a series of low carbon trials delivered throughout Westminster as part of the Council and FM Conway’s shared net zero ambitions, in which the partnership is using these new specifications to provide significant carbon savings compared to traditional materials and methods.

 

FM Conway and Westminster City Council have a longstanding history in pioneering the use of recycled content. A trial to lay an 80% recycled content surface in Sutherland Avenue in June 2019 was followed in 2021 by a warm mix surface course containing 85% recycled content on Third Avenue in 2021, and this latest improvement to 92% recycled content in Elmfield Way represents a further significant improvement in sustainable materials.