ICE and BSI refresh standard on lower-carbon concrete

The ICE and the British Standards Institution have published a new version of a BSI Flex standard designed to highlight the potential of lower-carbon concrete options and recommend their use.

With its production accounting for an estimated 8% of global carbon dioxide emissions, concrete imposes a huge environmental cost.

BSI Flex 350 – Alternative Binder Systems for Lower Carbon Concrete is a code of practice setting out the best way to identify possible decarbonised substitutes for traditional concrete and demonstrate their suitability.

Who should benefit from applying the standard?

BSI Flex 350 is freely available for anyone to use.

It’s designed to help infrastructure designers and contractors to recommend that their projects use concrete technologies that are lower in carbon than traditional mixes.

The standard is performance-based, meaning that mixes that may not have been covered by British standards before can be more readily considered for use as long as they meet the stringent criteria set by BSI Flex 350.

It will also help engineers and end-users to specify, and build with, a wider range of lower-carbon concrete technologies.

How the standard was created

The ICE and the Construction Leadership Council’s Green Construction Board published the Low Carbon Concrete Routemap (LCCR) in 2022.

Since then, the cross-industry UK Lower Carbon Concrete Group (LCCG) has been working to accelerate the decarbonisation drive. The updated BSI Flex 350 is an important milestone in this effort.

It also supports major low-carbon construction commitments made by the Infrastructure Client Group and the Construction Leadership Council this year.

The standard is the result of a collaboration between the British Standards Institution, the LCCG and the ICE (the primary sponsor), with thanks to a group of industry funders.

‘A key milestone’

LCCG chair and director of AMCRETE UK, Andrew Mullholland, said removing barriers to using new technologies is key:

“Considering new and innovative ways to use materials is essential to creating a sustainable future, as well as removing actual or perceived barriers to adoption of new technologies.”

“This Flex Standard is a key milestone in enabling the decarbonisation of infrastructure’s most ubiquitous material.

“I encourage those across the sector to use the new code of practice to explore lower carbon alternatives in their projects,” Mullholland said.

Have your say

BSI Flex standards are designed to be reviewed and updated to reflect technological advances and potentially be turned into international standards.

The first version of BSI Flex 350 was published in October 2023 and underwent a public consultation.

This second version was revised in light of the feedback gathered and has been peer-reviewed by an advisory group.

Comments about it can be submitted via the BSI Flex 350 webpage.

To engage with the concrete decarbonisation drive, read about the LCCR and/or contact Hannah Besford, ICE programme specialist, at [email protected].