On solid ground: Assessing the scale-up potential of structural stone in the UK

Concrete, a ubiquitous material in construction, is primarily composed of crushed limestone bound by cement, the production of which accounts for over 8% of global carbon emissions. Solid stone, in contrast, requires significantly less energy to produce, with its processing limited to extraction, cutting, and transportation. This makes it an increasingly attractive low-carbon alternative. Recent collaborations between structural engineers and stonemasons in the UK have demonstrated the technical feasibility of load-bearing and prestressed stone building systems. However, the potential for scaling up the use of structural stone in construction remains largely unexplored. To assess the scale-up potential of structural stone in the UK, our research employed a qualitative and quantitative design involving 19 in-depth interviews with stone quarry and mine managers across the UK and Europe. We found that, as perceived by our sample of interviewees, the biggest reported bottleneck to scaling up structural stone production in the UK is the availability and cost of labour; that a change in architectural preference of aesthetics and stone sizes could reduce waste, energy use and drive down costs; that there is lack of demand for structural stone products despite the increasing interest in it as a low-carbon material; that the decarbonisation potential of stone rests on investment in the sector; and that the total stone resource is not limiting but the process to extend existing, or open new, quarries needs streamlining to allow for rapid scale up. We anticipate our study to be a foundation for strategic planning and investment, enabling stone to reduce the embodied emissions of buildings and be produced economically at scale. • The ultimate resource of stone for use in load-bearing construction is not limiting. • Labour costs and availability are key bottlenecks to scaling structural stone production. • A change in architectural preference of stone in construction could reduce waste, energy use, and production costs. • Investment is crucial to realise stone's potential to decarbonise construction.