Getting London heat ready: how we’re building a fairer and more resilient city

This post is by Mete Çoban, deputy mayor of London for environment and energy as part of our essay collection How to get Britain climate ready. 

Extreme heat. Scorched parks and wildfires. Unprecedented pressure on emergency services. The climate crisis is here, and it’s everyday Londoners who are paying the price. London faces more extreme heat than anywhere else in the UK, and it is only going to get hotter.

We launched London’s first heat plan, Heat ready London, during this year’s London Climate Action Week, in the middle of one of the hottest periods our city has ever experienced. Temperature records for May and June were broken one after another, as the UN secretary-general warned that London was “cooking”. For only the second time, the Met Office issued a red warning for extreme heat.

The climate crisis is no longer a disaster that belongs to some distant future. It’s happening all around us, and it’s happening now.

Just talk to the people affected. The nurse caring for patients during a heatwave in a hospital with no air conditioning. The teacher supporting children struggling to concentrate in an overheated classroom. The older Londoners, the very young and those already living with physical or mental health conditions whose health can worsen when temperatures rise.

Heat is now one of the most serious and fastest growing threats to our health, our economy and the infrastructure we rely on every day.

During this summer’s heatwaves, the London Ambulance Service dealt with 25,000 more calls than last summer. Demand was higher than it was during the peak of the Covid-19 pandemic. In July 2026, the London Fire Brigade received more than 280,000 emergency calls and dealt with 13,000 incidents. Blazes damaged homes, businesses and precious green spaces.

The 2022 heatwaves are estimated to have cost the city £1.5 billion, reflecting their catastrophic impact on health, education, transport, energy use, emergency services and the environment, not to mention lost productivity. A report commissioned by City Hall (London Climate Resilience Review, 2024) warns this will only increase in coming years, with climate change potentially costing the city up to £36 billion a year by the 2050s if we don’t take action today.

Heat is also an issue of fairness. Not everyone experiences a heatwave in the same way. Some people can stay cool indoors or work in air-conditioned offices. Others spend long hours working outside or return home to homes that trap heat long into the night.

I think often about the communities around the estate where I grew up in Hackney. It’s often those with the fewest resources who feel the impact of climate change first and hardest. It’s the families with less access to green space. The workers who don’t have the option of staying inside when temperatures soar. Londoners on lower incomes are often the people who face the greatest risks.

For some, heat can also be deadly. Tragically, the latest heat-related mortality data suggests we may be on track for record numbers of heat-related deaths this year. Heat doesn’t even have to be extreme to be dangerous, either. Around 90 per cent of heat-related deaths in London occur on days between 24°C and 32°C, with Londoners aged 45-65 at higher risk than other people of the same age nationally.

This is why we must act now.

Building a more resilient London isn’t just about managing higher temperatures. It’s about reducing inequalities and making sure support reaches the people and places that need it most.

In 2025, we asked Londoners what they thought should be done. More than 3,500 people responded. They told us they wanted more trees and green spaces, more shade, better access to water and practical support to make their homes, schools and neighbourhoods cooler.

Their message was clear: Londoners want a city that is prepared for a warmer world.
That’s why the mayor of London, working with London councils and partners across the capital, developed Heat ready London. It sets out a shared vision for helping our city adapt to our changing climate.

Heat ready London focuses on six key areas: our built environment, businesses and the economy, emergency preparedness, green and blue spaces and nature, health and care services, and the infrastructure that keeps London moving.

Importantly, this is about moving from reacting to heatwaves as one-off emergencies to preparing for the reality of climate change. We need to make sure our homes, schools, hospitals, transport networks and public spaces are ready not just for the next heatwave, but for the decades ahead.

The good news is that many of the solutions we need to make London a better place to live already exist. And we’re already taking action.

Trees are one of London’s most effective natural defences against extreme heat, cooling down our streets and public spaces by up to six degrees. But greener streets don’t just keep us cooler, they improve air quality, support wildlife and benefit our mental and physical health and wellbeing.

Since 2016, the mayor has planted over 640,000 trees across the city and created or revitalised the equivalent of more than 2,000 football pitches of green space. City Hall is also funding up to 5,000 more climate resilient trees and increasing tree canopy cover in the neighbourhoods that need them most.

Homes designed or retrofitted to stay cool aren’t only more comfortable during summer, they can also be healthier, more energy efficient and more affordable to run. We’ve already retrofitted 1,000 homes across the city with Warmer Homes London. Through the mayor’s Home Energy Saving Fund we’ve announced an additional £58 million to upgrade up to 5,000 more of London’s most energy inefficient social homes, saving them up to £500 a year on their energy bills.

The same goes for public transport: a transport network that can cope with hotter temperatures isn’t just more resilient, it’s better for London’s economy and more comfortable for the millions of people who depend on it every day. More than 190 Tube trains – around 40 per cent of the Underground fleet – are already air conditioned, alongside all London Overground and Elizabeth line trains. Transport for London is now investing in new air-conditioned trains on the Piccadilly line and DLR, as well as expanding its fleet of air-conditioned buses and improving cooling and ventilation across the network. All of this will ensure we have a transport network which is fit for the future.

We’re also transforming London’s waterways over the next ten years through the mayor’s Clean Rivers and Healthy Waterways Plan. This will expand access to our city’s blue spaces, so that Londoners have more spaces to cool down.

This includes through swimming, where it’s safe to do so, and other opportunities to spend time in or near water.

The scale of the challenge we face is vast, but so are the opportunities on offer.
By acting now, we can create a greener, fairer and healthier city for everyone. We can reduce inequalities, protect vulnerable Londoners, and build neighbourhoods that are better places to live for the people who are proud to call them home.

Today, London is leading the way in showing how cities across the UK respond to heat. Our success, I believe, is testament to the power of partnership. We’ve brought together boroughs, health and care system partners, emergency responders, infrastructure providers, business and finance partners and community groups to turn the vision into action.

We also need to acknowledge that the best ideas often come from the people experiencing these challenges in their daily lives. That’s why it’s so important that we continue listening to Londoners every step of the way.

The choice before us is clear. We can carry on reacting to heatwaves, and paying the price through worsening disruption, poorer health and bigger bills. Or we can work together to build a city that is ready for the future.

Time and again throughout our city’s history, Londoners have shown that, when we come together, we can overcome the obstacles in our way. Now, we must do so again. By working together, we can make our city fairer, more resilient and better prepared for the decades to come.