France's heat wave trend: windows painted with chalk are emptying shop shelves

A heat wave sweeping across Europe has prompted French people to use a simple and inexpensive trick-painting windows with chalk. The centuries-old method, which has gone viral on social media, has created an unexpected surge in demand, with chalk paint running out in stores.

A heat wave gripping Europe has forced French people to search for simple and affordable solutions to cool their homes. A trend is now spreading on social media where windows are painted over from the inside with chalk, causing unexpected demand and depleting chalk paint supplies in shops.

Although the trick may seem unusual at first glance, it actually has a scientific basis. Chalk is white and reflects sunlight, reducing the penetration of solar radiation through glass and thus keeping rooms cooler. It is a method that was used across Europe long before modern sun protection existed.

The trend gained momentum on social media, where users shared photos and videos of chalk-covered windows and confirmed that it actually works. The historical background lent credibility to the tip, and it spread rapidly across France.

The solution's popularity demonstrates how hot summer days drive people to find cheap alternatives to air conditioning, which is either absent or too costly to operate in many older European homes.