How do you keep your home cool when it's hot outside?
Press release
Extreme heatwaves are turning our homes into thermal traps: it's time to act
Every summer, temperatures hit new records. In 2023, France experienced its longest-ever heatwave, affecting 52 départements and placing 19 million people on red alert. As these events become increasingly frequent, one thing is clear: our homes are not designed to withstand such heat. It’s urgent that we rethink our relationship with housing.
Our homes are not ready for the heat
Most of the French housing stock was built before the 1970s, when the main concern was insulation against the cold. As a result, few buildings are adapted to extreme heatwaves, which are becoming both more common and more intense. During heat peaks, indoor temperatures can soar well above 30°C, turning homes into furnaces—often hotter inside than outside.
A major and underestimated health risk
Heatwaves are often associated with risks for the elderly, but in reality, everyone is affected. In 2022, nearly 2,800 deaths were attributed to heat, including among people with no pre-existing conditions. Poor sleep, constant overheating, chronic fatigue, and concentration issues are increasingly common symptoms during the summer. Thermal discomfort is not a minor inconvenience—it’s a public health issue.
Solutions exist—they are sustainable and effective
There are many ways to address this challenge. Unlike air conditioning, which is energy-intensive and often ineffective during extreme heat peaks, passive strategies offer long-lasting results:
- Installing outdoor solar protection such as awnings, sunshades, or textile pergolas helps reduce direct sunlight exposure.
- Adding vegetation to façades or rooftops helps naturally cool the air.
- Night ventilation, combined with high thermal mass materials, helps maintain stable indoor temperatures.
These approaches are even more effective when integrated into a broader energy renovation strategy, combining summer comfort with environmental performance.
As heatwaves grow more intense, we must shift our perspective. It’s no longer just about renovating to heat better—it’s about renovating to cool better. Urban planners, architects, local authorities, industry players, and citizens alike all have a role to play in evolving housing standards in France.
Fighting urban heat islands and improving thermal comfort in homes must become top priorities. Only then can we build cities that are sustainable, inclusive, and resilient in the face of climate change.