S30129 Road Design DMRB Standards Research & Development CD127, CD109 & CD116

Description

National Highways is commissioning a programme of research to review and potentially modernise key road design standards, with a strong focus on safety, efficiency and future capacity of the strategic road network. This work will examine whether motorways and major roads could safely carry more lanes than currently allowed, and whether alternative road layouts (such as 2+1 or 2+2 configurations with central barriers) could deliver similar performance at lower cost, while maintaining or improving safety. It will also assess whether current design rules around speed and visibility (including how we set design speeds for rural roads and how small objects must be detectable by drivers) are still appropriate, as these have direct implications for collision risk and compliance. Finally, it will review the design of large, complex junctions (such as major roundabouts) to ensure current standards do not contain gaps that could lead to operational issues or safety concerns. This work is important and time-sensitive because existing standards may be limiting capacity, increasing costs, or unintentionally introducing safety risks, and updating them could enable more efficient, safer and more deliverable schemes across the network.