Introduction
2003 was a record-breaking year for France. Hospitals were inundated with emergencies as extreme weather hit the country and temperatures soared to 37 degrees Celsius. Hundreds of schools closed – conditions simply too unbearable for learning. At the time this was considered unprecedented. But in 2019, extreme heat returned, not just in France, but much of Europe. Some experiencing temperatures of over 40 degrees Celsius. Schools were once again forced to close as conditions became unbearable and unsafe.
As Europe may face a temperature increase of up to +4 degrees Celsius by 2100, concerns over the overheating of buildings are becoming a real issue to address. In France, a special project was launched by public bank, Banque des Territoires to fund the deep retrofit of all school buildings in France to prevent overheating.
Alexis Damia, Public Affairs Manager for Somfy, delves into this groundbreaking project to counter the effects of extreme heat and futureproof educational settings for young people in France.
The overheating problem for schools in France
Many school buildings, particularly older ones, were not designed to cope with extreme weather. Classrooms can quickly become uncomfortable during the hotter months, making it harder for students to concentrate and for teachers to deliver lessons effectively. As we’ve seen over the past few years, temperatures become so extreme that schools are forced to close, disrupting education and placing pressure on families.
The problem is often made worse when buildings are poorly insulated. This is not just an issue for old buildings. Large south-facing windows with little shading, and a lack of natural ventilation are design features that are common in more modern estates as well, where climate control has not been baked into the initial design – or not considered necessary or viable, until now.
Temporary fixes, like using fans or keeping blinds drawn, are rarely enough — and turning to air conditioning only increases energy use and emissions, creating a new set of challenges.
Without proper adaptation, overheating in schools threatens both educational outcomes and long-term sustainability. As the climate continues to warm, it’s clear that schools need targeted investment to become more resilient, energy-efficient, and comfortable for all who use them.
Adaptation – what is a deep retrofit?
Retrofitting buildings to deal with the effects of climate change isn’t just about giving your building a facelift. It’s about adding the right features to help buildings cope with extreme weather – but, most importantly, prioritising the comfort and wellbeing of the people who use the indoor spaces every day.
Technical guidance on how buildings can adapt to climate change has been issued by the EU, with a strong focus on tackling ‘heat stress’ — the combined impact of high temperatures and dry conditions.
Key recommendations include:
The renovation project saving schools from damaging heat
In 2023, Banque des Territoires — France’s public investment bank — launched a major programme to retrofit all school buildings across the country in response to climate change and rising heat levels. The goal is to future-proof schools and reduce their vulnerability to extreme temperatures.
So far, over €2 billion has been raised to support this effort. The funding is helping local authorities with tailored engineering and technical support to upgrade around 10,000 educational buildings — from nurseries to secondary schools — by 2027.
The aim is to cut energy use by at least 40% in renovated buildings and improve climate resilience through measures such as:
In addition to this program, and since 2025, local authorities wishing to receive public funding to renovate their buildings (not just schools) are required to carry out work to improve summer comfort, including the installation of solar shading systems.
Retrofit in action
The City of Poissy – located just outside of Paris – tackled the urgent issue of overheating in its public schools with some exceptional outcomes. The goal was to keep classrooms comfortable without relying heavily on energy-intensive air conditioning.
The city developed a heatwave response plan and launched a three-year retrofit programme across 15 public schools.
But every building presented a different set of circumstances. Cutting edge technical expertise was needed to determine the most effective solutions for each building. Engineering firm, Alterea, a specialist in thermal performance, was appointed to conduct studies comparing various retrofit solutions.
The studies found that high-performance external solar blinds offered the best cost-effective ratio for passive cooling. ZIP blinds were produced by Schenker Stores using thermal fabrics from Mermet and these were motorised using Somfy’s durable, automation-ready systems.
As part of this effort, 616 motorised ZIP exterior blinds were installed by experts, Stores Seas. This simple but effective solution transformed windows from sources of heat gain into tools for climate control—helping to maintain comfortable indoor temperatures, allowing natural light in, and reducing the need for mechanical cooling.
And the results speak for themselves: -
The economic impact as a result of the retrofit of school buildings is also significant. Highlights include:
Conclusion
France’s nationwide school retrofit programme and the efforts demonstrated by the City of Poissy, show how urgent action, robust regulation and strategic investment can help public buildings adapt to a changing climate. Local authorities have acted quickly, making summer heat resilience a requirement for receiving public renovation funding. This shows a clear commitment to futureproofing public infrastructure. As overheating becomes a growing concern across Europe, especially in educational settings, projects like this demonstrate that practical, scalable solutions exist — and they deliver real benefits for energy efficiency, comfort, and wellbeing. Creating climate-resilient schools isn’t just an economic or environmental goal. It is a social priority that ensures safe, healthy learning environments for current and future generations.
