Heat-related deaths could triple without action on homes, scientists warn

Temperatures in the UK reached an historic high of 40°C today - a record that is expected to soon be surpassed. Without a major overhaul of the country's infrastructure, these extreme conditions could lead to soaring numbers of heat-related deaths. 

Much of England and Wales are currently under a ‘red’ extreme heat warning, with daily record-breaking high temperatures causing disruption on transport networks and posing a serious risk to the health of the population. With the possibility of this heat becoming a ‘new normal’ for large parts of the country, government climate change advisors have highlighted the need to address the problem of overheating in UK homes - or face deadly consequences. 

The UK has little regulation to prevent overheating in new buildings, despite the fact that as many as 4.6 million homes overheat every year in England alone, according to a recent survey by Loughborough University. 

If no action is taken to keep homes from overheating, scientists fear that heat-related deaths could triple over the next 10 years. 

"We've been telling the government for over 10 years that we are nothing like well enough prepared in the UK for the really hot weather we are seeing now," Baroness Brown, deputy chair of the Climate Change Committee, told the BBC. "We really do need to address the overheating risk in peoples' homes."

Heatwaves caused an additional 2,000 deaths in 2020, according to the UK Health Security Agency. Most of these heat-related deaths can be linked to heat inside homes, but it was not until June this year that the UK government brought in regulation requiring new build homes to be tested for overheating. 

This Tuesday, UK temperatures exceeded 40°C in the UK for the first time on record, with 40.2°C reported at Heathrow at 12.50pm on Tuesday, according to provisional Met Office figures. This is only the latest heat-related record that the country has hit over the last week, with the UK expected to continue to rise over the coming days and in the years ahead. 

“By 2050, we will regularly have temperatures above 35°C in the south of the UK,” said Chloe Brimicombe, a heat stress researcher at the University of Reading. “By the 2050s between 5,000 and 7,000 people will die annually from extreme heat every year.”

New-build flats in city centres have been identified as the types of homes at the highest risk of overheating, yet more than half a million new homes liable to overheating have been built in the UK since it first raised the issue almost a decade ago, according to the Climate Change Committee. 

The lack of regulation is visible in the country's housing stock, says James Prestwich of the Chartered Institute of Housing, which represents housing professionals.

"We've seen buildings designed that don't cope well with the increased temperatures we now experience in summer," he said. "What we've seen is buildings that have been built with a lot of glass and not necessarily the best throughflow of air through corridors."

Heat stress exacerbates underlying conditions such as asthma, heart disease and mental illness. The symptoms of heatstroke - including confusion, cramps and fatigue - can be hard to differentiate from other medical conditions, including Covid-19, making the true scale of the health risk presented by Britain's overheating homes hard to assess. Often, heat is not even mentioned as a factor on death certificates. 

Despite the increasingly concerning health risks, it could take years for the rules on overheating in new homes to make an impact, as there is currently no policy for existing buildings nor for permitted development when existing units such as office blocks are turned into homes. Research has suggested that almost 20 per cent of bedrooms in English homes overheat in the summer months.

Moreover, retrofitting homes to reduce overheating can be very expensive, according to Professor Kevin Lomas of Loughborough University, who has spent more than two decades studying overheating in British homes.

“We live in a cool damp country and so our housing stock is built primarily for trying to keep us warm in winter, with almost no consideration of hot summer conditions,” he told the i newspaper. “The Government should be more keen than it is… to retrofit houses so that they are more energy-efficient.”

Although many homes will need new windows or air conditioning, Lomas indicated that simple measures such as electric fans and closing windows and curtains during the heat of the day and then opening them at night to let in cooler air can provide some immediate help. In the medium-term, insulation and heat pumps can help manage higher temperatures, as well as keep homes warmer in the winter months. Heat pumps, after all, can cool homes as well as heat them.

Last month, the government announced its plans to divert over £1bn from existing projects to help low-income households insulate their homes, in order to protect them from the cost of living crisis. However, the Climate Change Committee (CCC) said that the UK has not invested enough money in tackling energy efficiency in UK homes and buildings ahead of targets to reach net zero by 2050.

Lomas and the wider scientific community have called for further government action to protect the population from the threat posed by the warming of the planet. 

In addition to homes, the wider UK infrastructure is in need of an overhaul, according to advisors, in order to adapt to the extreme temperatures that have been predicted for the years to come. UK homes are predominantly built to stay warm during relatively mild winters, while infrastructure such as hospitals, trains and power lines struggles in hot weather and are often pushed to the point of crisis. 

“Heat scientists have for years been telling the government to prepare for this. This event is happening, we have very little preparation in place,” said Brimicombe. “We need mass mobilisation and real leadership from whoever the next government is – they need to listen to the advice of scientists urgently.”