A new peer-reviewed study from the University of East London has warned that extreme heat is rapidly becoming a silent public health emergency across the United Kingdom, with older people, hospital patients and low-income families facing the greatest danger as buildings trap rising temperatures inside.

Researchers say overheating is no longer simply an architectural problem. It is now a growing health crisis linked to climate change, poor housing design and weak policy enforcement. The findings come as the UK continues to record hotter summers, longer heatwaves and rising heat-related deaths.

The study, led by Dr Mehri Khosravi of the university’s Sustainable Research Institute, found that many homes, hospitals and care facilities are dangerously unprepared for prolonged periods of heat. Ironically, some modern energy-efficient buildings may be making the problem worse. Airtight insulation designed to keep homes warm during winter is also trapping heat during summer months, turning indoor spaces into what experts describe as “heat boxes”.

In care homes and hospitals, the risks become even more serious. Older people often struggle to regulate body temperature, while patients with heart disease, breathing disorders or dehydration face a higher chance of medical complications during extreme heat. Doctors and nursing staff are also forced to work in stressful indoor conditions that can affect patient care.

“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,” said Dr Khosravi.

The researchers gathered evidence from housing experts, healthcare planners and climate specialists during a national roundtable discussion. Their findings suggest that current UK building rules under Part O of the Building Regulations remain too weak and are inconsistently applied, especially in older buildings where millions still live.

The report also points to low public awareness as a major problem. Many people still do not recognise indoor overheating as a serious health threat. During recent UK heatwaves, indoor temperatures in some flats reportedly crossed safe limits even at night, leaving residents unable to recover from daytime heat exposure.

Scientists across Europe have repeatedly linked rising temperatures with increased hospital admissions and heat-related deaths. According to public health experts, climate change is making such events more frequent and intense.

“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,” Dr Khosravi added.

The researchers are now urging stronger heat protection laws, better NHS preparedness and immediate reforms to make homes safer before future heatwaves turn deadly.