Nikka Sulton

The Mayor of London, Sadiq Khan, has announced a new strategy to help tackle the growing problem of overheating in homes as the capital experiences increasingly frequent periods of hot weather.

The initiative, called Heat Ready London, sets out a long-term framework to improve London’s resilience to rising temperatures. It includes new requirements for the design of future homes, as well as plans to upgrade existing properties that are most vulnerable to excessive indoor heat.

The announcement comes as the housing sector is already preparing for further energy-efficiency changes, including the government’s proposed requirement for privately rented properties to achieve a minimum Energy Performance Certificate (EPC) rating of C by 2030.

More than one million homes could be at risk

According to research from the London Assembly, more than one million homes across London are considered to be at a high risk of overheating.

As climate change continues to bring warmer summers and more frequent heatwaves, indoor temperatures are becoming a growing concern. Homes that retain heat for long periods can affect residents’ comfort, wellbeing and health, particularly among older people, young children and those with existing medical conditions.

The Mayor said rising temperatures are no longer a distant environmental issue but an everyday challenge that is already affecting homes, schools, hospitals, care services and local communities throughout the capital.

Introducing the Heat Ready London plan

Sadiq Khan described Heat Ready London as London’s first dedicated strategy focused specifically on preparing the city for extreme heat.

The plan aims to create a coordinated approach that brings together government bodies, local councils, developers, housing providers and other organisations to improve the city’s ability to cope with rising temperatures.

Rather than relying on a single organisation to address the issue, the strategy encourages collaboration across the housing sector to deliver practical solutions that help protect residents while improving the resilience of London’s built environment.

New-build homes designed to stay cooler

One of the key proposals focuses on the design of future housing developments.

Under the London Plan, new homes will be expected to incorporate features that reduce the likelihood of overheating during warmer weather. Developers will be encouraged to use passive cooling measures such as improved shading, increased natural ventilation, better building orientation and smarter design techniques.

These design principles aim to keep homes comfortable without increasing dependence on air conditioning or other energy-intensive cooling systems. Reducing the need for mechanical cooling could also help lower energy consumption and support wider environmental objectives.

Existing homes will also need improvements

While new developments can be designed with future temperatures in mind, many existing homes present a greater challenge.

Large numbers of older properties were built without considering the effects of prolonged heat, making them more susceptible to overheating during the summer months.

The Heat Ready London strategy identifies retrofitting these properties as a priority. Proposed improvements could include measures that improve ventilation, reduce solar heat gain and increase overall thermal comfort for occupants.

The focus will be on upgrading homes considered to be at the greatest risk, particularly those occupied by vulnerable residents and those located in areas where high temperatures are most severe.

Cooperation across the housing sector

The Mayor acknowledged that addressing overheating across London’s housing stock cannot be achieved by one organisation alone.

The strategy calls for greater cooperation between central government, local authorities, housing associations, developers and private landlords to ensure homes remain safe and comfortable as temperatures continue to rise.

A coordinated approach is expected to be essential, particularly as climate adaptation becomes an increasingly important part of housing policy.

What it could mean for landlords

Although many of the proposals focus on London’s wider housing stock, landlords may also need to consider how rising temperatures affect the properties they let.

Alongside the government’s proposed EPC C requirements, improving a property’s ability to remain cool during hot weather could become a growing consideration when carrying out refurbishment or energy-efficiency works.

Landlords planning future upgrades may increasingly look at measures that not only improve insulation and reduce heat loss during winter but also help prevent excessive heat build-up during the summer.

Preparing homes for a changing climate

The launch of Heat Ready London reflects a wider shift in housing policy as climate resilience becomes a greater priority across the UK.

While improving energy efficiency has traditionally focused on reducing heating costs and carbon emissions, policymakers are now placing greater emphasis on ensuring homes remain comfortable throughout the year, including during periods of extreme heat.

By combining improved building standards for new developments with targeted upgrades to existing homes, London’s new strategy aims to create housing that is better prepared for future climate conditions.

As temperatures continue to rise, overheating is expected to become an increasingly important issue for homeowners, landlords, developers and policymakers alike, making climate resilience an integral part of the future of UK housing.