The two-year study by the UK Green Building Council outlines five major climate threats—overheating, flooding, drought, storms and wildfires—and warns that without urgent adaptation, public health, safety, and economic productivity are at severe risk.

The report's modelling predicts that towns such as Peterborough and Fairbourne could become uninhabitable by the end of the century due to flooding, while urban areas like London, Manchester, and Birmingham face rising risks from extreme heat and water stress.

Schools, care homes, and offices at risk

Using detailed thermal modelling, the report reveals that schools in London and the south-east could face 10 weeks of extreme heat—defined as days above 28°C—every year, even under a relatively low-warming scenario of 2°C above pre-industrial levels. The world is currently on track for 2.7°C of warming, the authors note.

Care homes, whose residents are particularly vulnerable, are projected to face at least four weeks of extreme heat annually in the same scenario. Meanwhile, around 6 million homes in the region could experience at least three weeks of such conditions, leading to reduced workforce productivity and heightened health risks for the elderly and those with pre-existing conditions.

Modern office buildings, often constructed with lightweight materials and extensive glass façades, are found to be particularly prone to overheating—making them less resilient than some older structures.

"The UK is not ready for the extreme weather events of today—let alone the even hotter, wetter and more violent climate that's coming," said Simon McWhirter, chief executive of the UK Green Building Council. "Our homes, schools, hospitals, and workplaces are on the frontline. We need a fundamental rethink to protect people and our way of life."

Call for urgent policy action

To address the mounting risks, the report sets out a five-point action plan, including:

• The creation of a Cabinet-level Minister for Resilience

• A new legal duty for planners to ensure all development is climate-safe

• A comprehensive retrofit strategy to prepare existing homes and buildings for climate hazards

• A more ambitious Future Homes Standard addressing overheating, flooding, and water scarcity

• Ensuring green space infrastructure—such as trees, parks and ponds—in all communities

The report criticises the UK government's new planning and infrastructure bill for lacking any legal mandate to make buildings resilient to the climate crisis. Instead, it argues, current policy puts excessive weight on economic growth at the expense of environmental preparedness.

Cities facing existential threats

Among the UK's most vulnerable cities, London ranks highest for risk from wildfires, droughts, and floods. The city of Peterborough is expected to face such significant flood damage that it may become uninhabitable by 2100. In Wales, the coastal town of Fairbourne is also projected to be overwhelmed by sea-level rise and tidal flooding.

The authors stress that adaptation efforts must go beyond installing air conditioning—which increases energy use—and instead prioritise passive cooling methods, such as solar shading, reflective materials, and the use of solar glass.

"Climate adaptation is not just about protecting property—it's about protecting lives," said McWhirter. "This roadmap gives us a plan. Now the government must act."

The UK Green Building Council is calling on ministers to treat the issue of adaptation with the same urgency as decarbonisation, warning that continued delay will have devastating social and economic consequences.