I am writing this Editorial while sitting in front of a fan, with the temperature outside my office reading 34°C. The environment is currently a topic almost as hot as the heatwaves hitting Britain. The construction sector sits at the centre of this challenge, facing increasing pressure to reduce its environmental impacts and embrace more circular approaches to resource use. Construction materials research has an important role to play in this transition.
There was a time when much of our attention was devoted to identifying waste streams and industrial by-products that could potentially replace conventional construction materials. During my own doctoral research, which focused on incorporating waste limestone dust into road foundation, the central question was whether such materials could be used at meaningful replacement levels without introducing unacceptable engineering consequences. My work eventually expanded to include other industrial residues (Saghafi et al., 2012, 2013), reflecting a broader research agenda of that period: diverting waste from disposal while maintaining acceptable engineering performance.
Today, the conversation has moved beyond simple material substitution. Researchers are increasingly challenged to demonstrate how alternative materials will perform throughout the service life of infrastructure. Durability, resilience, long-term behaviour and life-cycle performance now sit alongside strength and workability as measures of success. Viewed through this lens, the contributions in this issue collectively reflect what might be described as performance-driven sustainability.
The feature paper in this issue provides an excellent example of how sustainability assessments in construction materials research are becoming increasingly comprehensive. Focusing on the use of seashell ash as a partial cement replacement in mortar, Rani et al. (2026) move beyond simple claims of waste utilisation and undertake a detailed evaluation of both embodied energy and carbon dioxide emissions. Particularly noteworthy is the inclusion of transportation impacts and processing requirements within the environmental assessment, offering readers a transparent framework that could be readily adapted for evaluating other waste-derived construction materials. The study combines carbon and energy accounting with conventional engineering tests and microstructural investigations, using techniques such as scanning electron microscopy and chemical characterisation to help explain the observed mechanical performance. The result is a genuinely multidisciplinary contribution that demonstrates how environmental benefits, material performance and scientific understanding can be assessed together. As such, it provides a valuable reference point for researchers seeking robust methodologies for evaluating future waste-substitution strategies in cementitious materials.
As the construction industry increasingly turns to manufactured sand as a sustainable alternative to natural aggregates, questions inevitably arise regarding its performance under aggressive service conditions. Zhou et al. (2026) subject manufactured sand concrete to a demanding combination of drying, sulphate exposure and freeze–thaw cycles designed to replicate the complex environments encountered by infrastructure in service. The way they link macroscopic performance to microstructural behaviour is quite compelling. By combining mechanical and durability testing with detailed investigations of the interfacial transition zone, pore structure and microcrack development, they provide valuable insight into the mechanisms responsible for performance degradation. The findings demonstrate the benefits of nanomaterial modification over conventional supplementary cementitious materials and highlight the growing importance of multi-scale engineering approaches in extending service life and enhancing long-term durability.
For readers interested in how sustainability and affordability can be advanced without compromising engineering performance, Bui et al. (2026) offer valuable insights. Working with artificial lightweight aggregates produced from industrial by-products, they investigate an innovative surface treatment based on a combination of epoxy resin and hibiscus leaf extract. Through a comprehensive programme of physical and mechanical testing, supported by detailed microstructural characterisation, the study demonstrates how bio-based additives can contribute to denser aggregate surfaces, reduced water absorption and enhanced concrete performance. The paper goes a step further by exploring the relationship between aggregate-scale modification and concrete-scale behaviour, reminding readers that improvements achieved at one scale do not necessarily translate directly into optimum performance at another.
Sustainable construction is often discussed in terms of materials, but some of the most impactful research begins with a broader environmental challenge. Sharma et al. (2026) address the growing accumulation of pine needles in the Himalayan region, a biomass waste that contributes to forest-fire risks and ecological pressures, and explore how it can be transformed into a useful construction product. The resulting hollow mortar bricks not only demonstrate encouraging mechanical performance but also illustrate how locally available waste resources can be redirected into value-added applications. The decision to extend the study beyond material characterisation and consider a potential infrastructure application through the development of a pilot constructed wetland system shifts the research value even higher. Such an approach highlights the importance of identifying innovative ways to contribute to more resilient and resource-efficient infrastructure.
Working with two abundant agricultural residues, Moussa and Moawad (2026) undertake a comparative assessment of their influence on workability, mechanical properties, durability-related behaviour and thermal performance of concrete. The value of the work lies not only in identifying a promising fibre source, but also in demonstrating the importance of evaluating alternative materials through a wider performance lens. By examining both engineering and thermal characteristics within the same experimental framework, the authors provide a useful basis for understanding the trade-offs and synergies associated with fibre-reinforced sustainable concretes. The finding that not all organic fibres contribute equally to concrete performance is equally important, reinforcing the need for careful material selection.
Finally, readers are reminded that the journal’s latest accepted papers are published online through Emerald EarlyCite, providing rapid access to new research and enabling the construction materials community to engage with emerging developments well before they appear in a scheduled issue.
