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The government’s latest household survey data shows that the discomfort many people are experiencing during recent heatwaves in England is part of a pattern of overheating that is getting worse, Nesta has warned.
The research and innovation group said that households need guidance on cooling methods, particularly air conditioning, which it noted can be a low-carbon option.In particular, the new data finds that between 2019 and 2024, the proportion of occupied dwellings in England where households reported overheating increased from 7% to 12%, from 1.7 million to 3 million, the research group warned, in an analysis of the data.
In the face of the increase in overheating, many people were still having to resort to more traditional methods of cooling, Nesta noted. The most common methods of keeping cool in 2024-25 were reported as opening the windows (90%), closing shutters/curtains/blinds (75%) or using a fan (59%).
Just 8% of survey respondents reported turning on air conditioning (AC) – a fact which Nesta said highlights that more needs to be done to ensure people are getting help adapting homes to extreme heat (and humidity) in the UK – and that home decarbonisation can go hand in hand with making air conditioning a key pillar in helping people to cope with the heat.
Andrew Sissons, director of sustainable future at Nesta, said:
Anyone sweltering in this long-haul heatwave will recognise their own experiences in today’s figures showing that the number of people reporting overheating in their own homes has almost doubled in five years. As we experience hotter temperatures each summer, it is a real concern that for many people home is no respite. Overheating is not trivial – not only does it cause discomfort and reduces productivity, including for many people who work from home – but it is a big health risk, with rising excess deaths due to heat, particularly among older people.”
He underlined that AC can be part of the solution – and can reduce carbon emissions compared to fossil fuel heating. He said:
Most air con units are air-to-air heat pumps, which can be used for much-needed cooling in summer and as a very efficient electric heat source to replace fossil fuel systems like gas boilers in winter. People will soon be able to get £2,500 towards replacing their boiler with these heating and cooling systems, but the government could make further tweaks to make this the easy choice for more people.”
Built-in air conditioning units are mostly delivered as air-to-air (A2A) heat pumps, meaning they can work as a low-carbon heating system too, he added. England currently lags behind other countries when it comes to AC uptake, with under 5% of homes in England having AC, compared to 24% in France, 60% in China and 91% in Japan.In April, it was announced that the government’s Boiler Upgrade Scheme (BUS) will offer £2,500 grants for certified installations of air-to-air heat pumps.
In addition, a new government report has found that A2A heat pumps, together with supplementary electric heaters (such as those used in bathrooms), provided space heating at a greater combined efficiency for three out of five home archetypes, when compared to other types of heating systems (including combi gas boilers).
Nesta said that this summer could be an opportunity for the UK government to consider expanding permitted development for two outdoor heat pump units to other property types (non-detached). Similarly, the Leasehold and Freehold Reform Act 2024 could be changed to reduce the challenges associated with strict leaseholds installing these kinds of systems, it said.
