Heidelberg Materials UK are supplying a lower carbon concrete solution to form the basement floors of a new retail and office development in London’s West End.

The company says it’s the first time their evoBuild low carbon concrete has been used in the UK. The product results in a carbon saving of 35% over standard CEM 1 and also produces improved durability. This made it the best choice for the building’s owners who are looking to achieve both NABERS 5* and BREEAM Outstanding ratings.

The evoBuild cement being used in the concrete is produced at Heidelberg’s Brevik plant in Norway, where the use of carbon capture and storage reduces the CO₂ emissions associated with its production by around 50 per cent. In addition, the concrete contains evoBuild GGBS, a by-product of steel making, which is less permeable than standard CEM I cement, increasing the durability of the concrete and extending its life.

Following a redesign of its 2018 planning permission for the building in question, the Crown Estate significantly increased its sustainability ambitions, reducing embodied carbon from 859kg/CO2/m² to 614-675kg/CO2/m².

Building on these design-stage improvements, material specifications continued to be reviewed and optimised throughout construction, with one of the most significant changes being the choice of evoBuild low-carbon concrete. The choice in fact reduced the project’s embodied carbon target to less than 515-550kg/CO₂/m².

Said Realtime Civil Engineering Contract Manager Colm Henry, “Previously, low carbon saving mixes affected the concrete performance on initial curing times but the evoBuild mix has overcome this issue. This benefits our overall carbon footprint with no compromise on our construction programme.”