Editorial: From research to practice – industry reflections on low-carbon concrete

The climate emergency has positioned the construction sector at the forefront of the global sustainability challenge. As one of the largest consumers of raw materials, the industry has both a responsibility and an opportunity to lead change.As a key pillar of the built environment, concrete supports infrastructure, buildings, data centres, industrial facilities and other critical aspects of modern life. Nonetheless, it carries a significant environmental impact due to its reliance on clinker-based cement, which is responsible for 14–17% of global direct industrial greenhouse gas emissions (IPCC, 2022). The demand for concrete is expected to remain strong, particularly in developing regions (WCA, 2025). Ultimately, the concrete industry faces a dual challenge – to continue delivering safe, durable and affordable structures, while dramatically reducing its embodied carbon dioxide footprint.Encouragingly, recognition of this responsibility is growing across the entire construction supply chain. These efforts go beyond regulatory compliance; they also respond to the expectations of investors, customers and wider society for responsible, modern business practices. For instance, the Infrastructure Clients Group (ICG) is playing a leading role in shaping demand for ‘low-carbon’ concrete through strategic initiatives, including the Concrete Decarbonisation Accelerator, which brings together industry, research and policy expertise to develop and adopt innovative solutions (ICE, 2024). Global industry-wide initiatives such as Climate Group’s Concrete Zero signal a collective acknowledgement that the sector must act, while many firms are aligning with the Science Based Targets initiative (SBTi) to demonstrate that their pathways are consistent with climate science. By promoting efficient concrete use, embedding low-carbon requirements in projects and sharing insights from early trials, these initiatives provide clear signals to the market. They reduce uncertainty for innovators and help overcome barriers related to cost, risk aversion and the lack of standardised specifications, supporting the wider adoption of sustainable concrete solutions.These developments point to an emerging cultural shift within the industry. Sustainability is no longer treated as an optional added-value exercise or a procedural formality, but is increasingly recognised as a core determinant of competitiveness and reputation. Achieving meaningful reductions in the carbon footprint of concrete requires coordinated action across multiple levels, from material innovation and testing through to specification, procurement and whole-life asset management. The simultaneous drive of industry associations, client groups and construction companies illustrates the scale of the opportunity and challenge to align efforts and build momentum for fundamental change.The papers presented in this special issue of Magazine of Concrete Research demonstrate that progress in low-carbon concrete is multi-dimensional. A single solution is unlikely to scale at sufficient pace to decarbonise the full extent of the growing demand for traditional concrete. At present, it is therefore paramount that different approaches are explored so that, combined, these could present a viable roadmap to net-zero.One prominent theme is the development of new binder systems, including alternatives to Portland cement, such as magnesium silicate hydrate composites. These materials show the potential for high performance with a distinctly lower carbon footprint, representing a more radical shift than incremental substitutions of supplementary cementitious materials (SCMs).A second theme is the evaluation of industrial and municipal by-products. Studies on pre-treated bottom ash, lagoon fly ash and waste foundry sand illustrate how residues commonly sent to landfill can be repurposed in concrete. This not only reduces embodied carbon dioxide but also advances circular economy principles. Nevertheless, these efforts reflect on the challenge of ensuring consistent material quality across diverse sources – a factor that is critical for safe, large-scale deployment.A third theme is application-focused research, which demonstrates the real-world performance of low-carbon concretes. The example of geopolymer concrete for pavement rehabilitation shows how novel materials respond to traffic loading, curing conditions and durability challenges. Such studies are essential for bridging the gap between laboratory performance and field adoption.Finally, one of the contributions emphasises the importance of life-cycle assessment and the necessity for tools to quantify carbon reductions and optimise design choices. These analyses help ensure that technical innovation translates into tangible environmental benefits, providing clients, regulators and engineering professionals with high-quality data needed to support adoption.Collectively, these contributions illustrate that innovation in low-carbon concrete is not conducted in isolation but is fundamentally interconnected with pressing industry needs. They provide a growing knowledge base to inform the development of standards, guide procurement and reassure insurers, helping transition promising technologies into viable, real-world solutions. Equally, the variety of solutions explored in the articles in this issue demonstrates the need for an array of options to radically decarbonise – at scale – a field as expansive as the concrete sector.Despite the pace of innovation, translating laboratory breakthroughs into reliable, widely adopted practice remains challenging. A recurring issue is scalability. Materials that perform well under controlled laboratory conditions may behave differently when produced in industrial volumes or applied under real-world construction conditions. For example, alkali-activated binders and other novel cement replacements have shown excellent mechanical properties in small-scale trials, but achieving the same consistency in ready-mix plants or on construction sites with strict deadlines can be difficult. Variability in raw materials, curing conditions and local supply chains can introduce inconsistencies that undermine the confidence of all construction project stakeholders.A second critical barrier is the availability and suitability of SCMs. Currently, many decarbonisation strategies rely on by-products such as pulverised fly ash (PFA), ground granulated blast-furnace slag (GGBS) or emerging sources like natural pozzolana. However, these materials are commonly finite, sometimes of variable composition and often regionally constrained. PFA, for instance, is declining in some areas like the UK as coal-fired power generation is phased out. GGBS availability depends on steel production in blast furnaces – a manufacturing route that is also under decarbonisation pressure (Scrivener et al., 2023). Emerging SCMs may help, but few currently have the capacity to meet the ever-growing global demand for cement in isolation. Without reliable, abundant alternatives, low-carbon concretes risk remaining niche rather than mainstream solutions.Beyond technical and supply-chain challenges, regulatory frameworks can often be a barrier to adoption. Structural codes are necessarily conservative, reflecting the wealth of experience with conventional concrete. Novel binders and unconventional aggregates often fall outside this regulatory basis, creating uncertainty for the industry. Without established guidance, underwriters may be reluctant to take on the inherent risk on projects and clients may hesitate to adopt new materials, particularly when long-term durability data are limited. The historic lack of codified assurance mechanisms compounds these barriers, highlighting the importance of building a robust evidence base for safety, structural integrity and long-term performance.Addressing these challenges requires more than material innovation. It demands simultaneous and collaborative development of supply chains, regulatory pathways and long-term performance data that can support engineering confidence and risk assurance. Only then can novel low-carbon concretes progress from pilot applications into mainstream construction.While the challenges are significant, recent developments demonstrate that conditions for the broader adoption of low-carbon concretes are improving. One of the most encouraging areas is the evolution of standards and codes, which are increasingly incorporating sustainability. Typically, standards have long revision cycles, leaving innovative materials outside of formal guidance. However, recent updates show meaningful progress.For example, the second generation of BS EN 1992-1-1:2023: Eurocode 2 (BSI, 2023a) now allows the assessment of concrete strength at up to 91 days, enabling fuller utilisation of lower carbon concretes with slower strength gain. Moreover, BS 8500-1:2023 (BSI, 2023b) has expanded options for composite cements, permitting up to 65% replacement of Portland cement, while removing some more prescriptive requirements, which have previously limited resource efficiency. Notably, BS Flex 350:2024 (BSI, 2024) explicitly addresses alternative binder systems, introducing a performance-based evaluation framework to accelerate the adoption of novel concretes.These changes, while promising, also highlight the fact that standards can only advance as far as the available data allows. To ensure safety, durability and long-term reliability, regulators require a robust knowledge base that captures real-world performance under varied conditions. This is where academic research, particularly when undertaken in partnership with industry, becomes indispensable. Industry identifies the critical uncertainties, such as scalability in large pours, curing regimes on site, unique performance requirements, their interaction with reinforcement or their long-term durability under aggressive exposure conditions, but academia is uniquely placed to investigate these questions with impartiality, from an expert, neutral viewpoint, unburdened by commercial risk, based on robust scientific methods and data.Collaboration between the two therefore becomes a key instrument of progress. Academic research expands the knowledge base that builds confidence in new materials, supports standards revisions and reduces the perceived risks that currently hinder adoption. At the same time, industry engagement ensures that research remains grounded in practical needs and prioritises the gaps most urgent for at-scale deployment. Successful examples of this model are already visible in university-led projects that have produced design tools and technology spin-offs now entering commercial practice. By jointly prioritising research that directly addresses operational challenges, industry and academia can accelerate the transition of low-carbon solutions from experimental trials to wide adoption across a multitude of real-world applications.The research presented in this special issue demonstrates both the challenge and the opportunity inherent in decarbonising concrete. Innovation in low-carbon concrete is multi-faceted, including novel binders, the valorisation of industrial by-products, application-focused innovation and robust analytical tools. These advances are building the evidence base needed for industry adoption without compromising safety, durability or structural integrity.At the same time, the challenges of scalability, supply-chain constraints, code compliance and long-term performance remain. The research presented here contributes towards the resolutions of these issues, providing practical insights that reduce uncertainty for stakeholders.Ultimately, reducing the carbon footprint of concrete requires collaborative action across academia, manufacturing, design, procurement and regulatory frameworks. Together, they accelerate the transition from laboratory innovation to mainstream adoption, ensuring that low-carbon concretes can be deployed safely and effectively. This special issue demonstrates increasing progress and builds the foundations so that a combination of incremental innovation and evidence-based practice can provide a clear pathway toward widespread adoption. Low-carbon concrete is no longer a distant ambition – it has become a viable necessity for delivering safe, durable and sustainable structures.