Supplying Sizewell C: How our limestone filler supports major UK infrastructure
As the UK continues to invest in major infrastructure projects to meet energy, environmental, and economic goals, reliable materials are essential for project delivery. LKAB Minerals is proud to play a key role in this transformation, supplying high-quality limestone filler to Sizewell C and Hinkley Point C, two of the most ambitious nuclear power stations currently under development in the UK.
Our limestone calcium carbonate powder, sourced from multiple UK locations – including our long-established Gurney Slade Quarry – is being used as a concrete additive to help meet modern construction requirements. As demand grows for more sustainable, high-performance concrete, limestone filler is proving to be a crucial part of the solution.
A material trusted on the UK's biggest construction sites
At Sizewell C and Hinkley Point C, the scale of construction is extraordinary. These projects are designed to provide low-carbon electricity for millions of homes, helping the UK achieve long-term energy security and net-zero emissions targets.
Supplying materials to such large-scale builds requires not only technical performance, but also logistical reliability. That’s why LKAB Minerals has been selected to provide limestone filler, a mineral filler that contributes directly to the performance of concrete used in critical structural components.
To maintain continuous supply and maximise efficiency, we supply limestone filler from multiple UK sites, selecting the source best suited to project timelines and regional logistics. Our Gurney Slade Quarry in Somerset is a key example of our UK production network, with a long history of delivering premium calcium carbonate filler to the construction industry.
Why limestone filler matters in concrete
Concrete is the backbone of infrastructure. But traditional concrete production is also carbon-intensive, largely due to the high clinker content in cement. In recent years, there has been increasing focus on reducing the clinker factor in concrete mixes by using supplementary cementitious materials (SCMs) such as limestone filler.
From late 2023, updated UK concrete standards now permit up to 20% limestone filler in concrete. This regulatory change creates new opportunities for both environmental and economic gains across the industry.
The benefits of using limestone filler in concrete include:
- Clinker reduction : Helps lower CO₂ emissions from cement production
- Improved workability : Enhances flow and compaction during placement
- Better surface finish : Reduces porosity and improves final appearance
- Consistent performance : Provides a fine, inert filler that maintains strength
- Cost efficiency : Reduces cement usage without compromising quality
These benefits are particularly important on large projects like Sizewell C, where thousands of cubic metres of concrete are poured in demanding environments. The ability to deliver high-performance, lower-carbon concrete at scale is a key reason limestone filler is gaining traction across the UK.
Supporting sustainable construction at scale
At LKAB Minerals, we take pride in supporting projects that align with the UK’s broader sustainability goals. Nuclear power is a core part of the transition to net zero, and the concrete used to build these facilities must meet rigorous sustainability and durability requirements.
By supplying limestone filler as a concrete additive, we help contractors reduce embodied carbon in concrete without compromising on the long-term strength and resilience needed for critical infrastructure.
Our limestone filler also supports circular economy thinking. Where our filler can be supplied in bulk or bagged formats, and excess filler can be recovered from customer sites through our silo recycling and collection services. This minimises waste and helps maintain cleaner, more efficient construction sites.
Why LKAB Minerals?
With decades of experience supplying mineral fillers to the construction, agricultural and manufacturing sectors, LKAB Minerals is a trusted partner for some of the UK’s most demanding projects.
We offer:
- National UK coverage with limestone supply from multiple quarries
- Consistent quality control , backed by in-house laboratory testing and XRF equipment
- Flexible delivery , including just-in-time supply from over 60 silos across the country
- Technical support , from product selection to concrete performance advice
- Compliance with BS-EN7979 and BS-EN13403 standards
Our limestone filler has a minimum calcium carbonate content of 70%, a maximum moisture content of 1%, and a bulk density between 0.5 and 0.9 Mg/m³, making it highly suitable for concrete and asphalt applications alike.
When it comes to concrete additive performance, purity, consistency, and supply reliability make the difference. That’s what LKAB Minerals delivers, every time.
Looking ahead
Sizewell C and Hinkley Point C represent a significant milestone in the UK’s infrastructure evolution. We’re proud to be part of the supply chain that supports their success.
As demand for low-carbon, durable construction materials grows, we expect limestone filler to play an increasing role across concrete, asphalt, and broader construction applications. At LKAB Minerals, we’re ready to support that growth with our high-quality limestone filler mineral. Contact our team today to request a sample, discuss your project needs, or explore how our limestone filler can support your concrete production. You can also follow us on LinkedIn for the latest updates, case studies, and product releases!
