The Lead Untangles: Why Britain isn’t built for the heat

Some may sneer at every heat-health warning, but high temperatures come with dangers our housing stock is not ready for. Can we improve things?

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Aug 15, 2025

silhouette photography of man standing in front of building — Photo by Talha Imam on Unsplash

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Britain is scorching and while it’s not like Brits to moan about the weather, as the climate gets hotter, it’s becoming increasingly apparent our homes can’t handle the heat.

As it stands, one fifth of homes in England overheat in current summer temperatures – which, of course, are destined to become hotter.

Britain’s housing stock simply hasn’t been built to withstand heat. Old, Victorian-era homes often have large windows and poor insulation, making them unsuitable for the heat. Meanwhile new builds are too often not designed well and are lacking in water-efficiency. Plus, installed air-conditioning (which is the norm in hotter European countries) is essentially banned in new houses, unless developers can prove they have exhausted all practicable passive means of cooling a building before getting permission to install it.

There is also a severe lack of green space and tree cover in England, which is vital for keeping homes cool. Some one in five people are deprived of green space in England, and almost half of neighbourhoods in English towns and cities have less than 10 per cent tree cover.

Context

This summer, we’ve experienced the second-warmest June and fifth-hottest July since 1884. Multiple regions across the country, West Midlands, East Midlands, South East, London, and East of England, have this week been slapped with amber heat health warnings, as we experience our fourth heatwave of the year, this time with temperatures peaking at 34 degrees.

In 2022, the UK experienced its hottest summer on record, reaching 40 degrees, which is likely to happen again.

While Labour has promised to build 1.5 million new homes – these new builds are often not being built to withstand extreme heat.

The government introduced some regulation to combat overheating in homes in June 2022, in Part O of the Building Regulations in England. It requires designers to limit glazing, maximise ventilation and utilise shading.

However, this only applies to new homes. Around 80 per cent of buildings that will be lived in and occupied in 2050 have already been built. The government’s Future Homes Standard is due to come into force in 2027, however the focus has been on how to keep homes warm in winter.

The government is, however, considering expanding its Boiler Upgrade Scheme to include air-to-air heat pumps, which means people would be able to get subsidised cooling technologies in their homes.

What does extreme heat actually do?

Hot homes lead to increased illness and deaths. Indoor temperatures above 25 degrees have been linked to increased cardiovascular and respiratory issues, mental health problems and heat exhaustion. Experts believe a temperature of 28 degrees inside the home is likely to become the norm in London and the south east in the decades to come.

Last year, 358 people died at home during the heatwave, due in part to extreme temperatures. Extreme heat can exacerbate illnesses such as pneumonia, the flu and circulatory diseases, causing an increase in related deaths.

Unsurprisingly, those on the lowest income are more likely to experience overheating in their homes.

Analysis by the Resolution Foundation found that people who owned their homes are much less likely to suffer from the risks of overheating. Two-thirds of socially renting households are at risk of their homes getting too hot compared to just 17 per cent for homeowners. It also found that almost half of minority ethnic households face the highest risk of their homes getting too hot.

What are people saying?

Green party MP Adrian Ramsey said: “We are entering the fourth heatwave this year. This isn't just a “once in a century". It's our new reality. We’re already paying the price of extreme heat. Across Europe, there were nearly 1,500 deaths after the heatwave in July linked to climate breakdown. Yet the Government still treats it like a one-off.”

The UK Green Building Council chief executive Simon McWhirter said :"The UK is not ready for the extreme weather events of today, even less so for the hotter, wetter and wilder climate that is already racing down the track at us. Our homes, schools, hospitals, parks and offices are on the frontline, protecting and nurturing us. We need a fundamental rethink if we are to help protect people and our way of life."

Friends of the Earth said: Many of the new homes in the UK aren’t designed to deal with heatwaves, and living in them is becoming unbearable for some. This is a health matter too – hot homes can be deadly. We need housing that can deal with a hotter future.”

What comes next?

There are solutions that would help fix the problem of homes overheating. Namely, the government could invest in greening up local areas. The UK Green Building Council advocates a 3:30:300 approach: the ability to see three trees from your home, 30 per cent tree cover in your neighbourhood, and being no more than 300 metres from a green space or park.

Housing developers could also use reflective materials to reduce the heating effect in densely populated areas and install shutters on UK homes.

But, for now, the UK remains wholly unprepared for rising temperatures.