Older people, care home residents and those living in poor-quality housing are facing growing danger from extreme heat, as new research warns that the UK is failing to protect those most at risk.
The study reveals that overheating is no longer just a design issue - it is an escalating public health challenge, with the greatest impact falling on people least able to adapt. Hospitals and care homes are among the highest-risk environments, where rising indoor temperatures are already affecting safety, care delivery and wellbeing.
Led by researchers at the University of East London (UEL), the paper highlights how gaps in building regulations, weak enforcement and low public awareness are combining to leave millions exposed as temperatures continue to rise.
Despite the introduction of overheating rules under Part O of the Building Regulations, the research finds these measures are limited, inconsistently applied and often fail to account for real-world conditions - particularly in existing homes and institutional settings.
In some cases, homes that meet modern energy efficiency standards may actually be more prone to overheating, as airtight construction and insulation trap heat indoors during summer months - exposing a critical flaw in current policy.
The research also shows that overheating is often addressed too late in the design process, meaning simple solutions such as shading or building orientation are missed. Developers are frequently left relying on last-minute fixes that do little to improve long-term resilience.
Beyond buildings, behavioural and institutional barriers are compounding the problem. Low public awareness of heat risk, unclear guidance during heatwaves and gaps in healthcare preparedness are all limiting the UK's ability to respond effectively.
The study draws on insights from a national roundtable of experts across housing, healthcare and the built environment, revealing widespread concern that current systems are not keeping pace with rising temperatures.
Among the key recommendations are extending overheating regulations to existing homes as well as new builds, strengthening enforcement, and embedding heat resilience into planning decisions from the outset.
The researchers also call for clearer, more actionable public guidance, alongside targeted support for vulnerable groups and stronger integration of heat risk into NHS planning and services.
Dr Mehri Khosravi, Senior Research Fellow at UEL's Sustainable Research Institute , and lead author of the study, said:
"Extreme heat is already putting the most vulnerable people at risk, particularly those in care settings and poor-quality housing. Yet our current systems are not designed to protect them."
She added:
"We need to stop thinking of overheating as just a building problem. It is a public health issue that requires coordinated action across housing, healthcare and climate policy."
The paper concludes that without urgent reform, the UK risks locking in homes and systems that will become increasingly unsafe in future heatwaves, with the greatest burden falling on those least able to respond.
The research, From building codes to behaviour: Strengthening extreme heat adaptation policy in the United Kingdom , is published in Energy Research & Social Science.
