A new report warns that over one million children in London could be at risk of health issues unless the capital's overheating homes are retrofitted urgently. The cross-party London Assembly Planning and Regeneration Committee has told Mayor Sir Sadiq Khan that 75 per cent of London's social housing stock is considered at high risk of overheating, potentially placing more than one million children at increased risk.
Record heat and rising deaths
This summer is on course to be the UK's hottest since records began, according to the Met Office, with longer and more intense heatwaves predicted in the future. Data released by the Office for National Statistics (ONS) shows that London had the highest proportion of deaths attributable to both the hottest and coldest days.
The committee's report states that London's homes are currently "ill-equipped to cope with the temperatures the capital is already experiencing, let alone those projected in future decades." A survey carried out by the committee found that 86 per cent of Londoners reported overheating in their homes in 2025, with many unable to sleep and suffering negative impacts on their mental and physical health.
Criticism of current rules
Max Anderson of the Conservative Environment Network said: "Whilst Labour continue to allow red tape to get in the way of air conditioning and greening up London, they are putting Londoners' lives at risk. Without air conditioning, London homes are turning into ovens that are threatening everyone from new-borns to pensioners." He added that "perverse, confusing rules on planting trees alongside roads make it nearly impossible for councils to green up cities."
David Simmonds, the Shadow Minister for Levelling Up, Housing and Communities, said: "Londoners are dying because of hairshirt anti-air conditioning rules. Confusing regulations for planting trees alongside streets is leading to less greenery across the city, exposing more residents to the full harm of these heat waves. This is not only hurting people's productivity and their day-to-day health, but is now killing Londoners at a disproportionate rate as our climate gets warmer."
Mayor's strategy and recommendations
City Hall has acknowledged that major reforms are needed to prepare the capital for extreme conditions. The Greater London Authority's (GLA) Heat Ready London strategy, unveiled in June, lays out plans to expand access to cool spaces and increase urban greening. However, the committee has now warned the Mayor that extra focus needs to be placed on accelerating the retrofitting of homes through passive cooling measures to ensure they are "fit for a warming climate."
The committee concluded that "more radical action" is needed both when building new homes and retrofitting current stock. They noted that many buildings are still being developed without adequate passive cooling due to a lack of enforcement of the GLA's 'cooling hierarchy'. During one committee session, Dr Tom Dollard told Members that designers often jump straight to ventilation with only a "notional nod to the more passive measures such as reducing window elevations and shading."
Passive cooling measures like external shading reduce indoor heat without consuming energy, while active cooling - air conditioning - should mostly only be adopted in "vulnerable" households. The committee encouraged the GLA to "embed overheating adaptation within wider retrofit activity," citing the example of the GLA and London Councils piloting shutters and awnings in their retrofit of 12,000 homes as good practice.
Chair James Small-Edwards said: "Too many Londoners are living in homes that become unbearably hot in summer, with extreme temperatures tragically contributing to hundreds of deaths. Current trends suggest that heatwaves exceeding 40 degrees are now 20 times more likely than they were in the 1960s, and yet London's homes have not adapted to this new reality."
A spokesperson for the Mayor of London told the Local Democracy Reporting Service (LDRS): "Extreme heat is a growing threat to Londoners' health, with around one million homes potentially at high risk of overheating. The report and its recommendations will be carefully considered. Through Heat Ready London and the Draft new London Plan, the Mayor is already working to protect those most at risk, reduce overheating in new and existing homes and make the capital more resilient as our climate changes."
