In 2015, France passed a landmark law requiring that all new commercial buildings must have rooftops either partially covered with plants (green roofs) or fitted with solar panels.

The main goals behind this rule were:

🌱 Environmental benefits

• Green roofs improve building insulation, reducing heating in winter and cooling in summer.
• They help absorb rainwater, reducing flooding risks in cities.
• They support biodiversity by providing urban habitats for birds and insects.

☀️ Energy transition

• Rooftop solar panels help reduce dependence on fossil fuels and cut greenhouse gas emissions.

🏙️ Urban quality of life

• Green roofs can reduce the “urban heat island” effect in cities.
• They make neighborhoods more visually appealing.

France was one of the first countries in the world to make such a rule mandatory nationwide, though initially it applied only to new commercial buildings. Since then, several cities worldwide (like Toronto, Copenhagen, and some German cities) have implemented similar requirements.