Every US state department of transportation and the District of Columbia now permit the use of Portland limestone cement (PLC). The Portland Cement Association (PCA) commends the Connecticut Department of Transportation’s approval of PLC in its projects, a move that means the entire US now accepts a lower-carbon version of a critical construction material. 

Developed with a higher limestone content, PLC offers the same level of efficacy as traditional Portland cement while having a CO2 footprint that is up to 10 per cent smaller. In 2023 alone, the US avoided emitting more than 4Mt of CO2 by incorporating PLC and other blended cement alternatives. The landmark arrives at a crucial moment: state transportation departments are major cement consumers, and this consumption will only increase as these agencies use Bipartisan Infrastructure Law funding to rehabilitate roads, bridges and other infrastructure. 

Mike Ireland, president and CEO of PCA, said, “This milestone is a huge step forward for sustainable American construction. Switching to Portland limestone cement promises to save millions of tonnes of CO2. Using a lower-emission product that meets all the performance requirements of traditional cement means the construction sector can build with durability, safety and sustainability in mind.” 

This new milestone reflects the growing adoption and availability of PLC, as well as efforts to reduce construction's carbon footprint. This shift toward sustainable construction materials is a positive step toward transitioning to a green built environment and is a trend that is expected to continue to grow, with recent US Geological Survey data revealing that the US market share for PLC surpassed that of traditional Portland cement in June 2023.