Green roofs in Île-de-France: benefits and grants in 2026

Green roofing: more than just a trend

Faced with global warming and urban heat islands, greening flat roofs has become an essential solution in the Paris region. But beyond the aesthetic and ecological aspects, a green roof offers numerous technical advantages for your building.

The advantages of a green roof

1. Extending the lifespan of the waterproofing

Did you know vegetation protects the waterproofing membrane? By absorbing UV rays and reducing thermal shocks (the sun no longer beats down directly on bitumen or PVC), soil and plants can extend the lifespan of your waterproofing by an additional 20 to 30 years.

2. Thermal and acoustic regulation

A green roof adds significant thermal mass:

• In summer: it prevents heat from entering (reducing air conditioning needs).
• In winter: it limits heat loss.
• It also attenuates noise pollution, a major asset right in the center of Paris.

3. Rainwater management

The City of Paris strongly encourages rainwater retention. A green roof retains between 50% and 80% of precipitation, thereby relieving sanitation networks saturated during heavy storms.

The vital importance of the waterproofing system

Planting on your roof cannot be improvised. The number one risk is water infiltration and root puncturing.

At FDM ENERGIE, we follow a waterproofing protocol specific to green roofs:

1. High-performance Vapor barrier
2. Thermal insulation suited to compression
3. Anti-root waterproofing membrane (often specific EPDM or bitumen)
4. Drainage layer (to drain excess water)
5. Filter layer (geotextile)
6. Substrate and vegetation (Sedum for extensive roofs, low maintenance)

Grants and subsidies in Île-de-France

In 2026, installing a green roof as part of a comprehensive energy renovation project makes you eligible for several forms of financial aid:

• MaPrimeRénov'
• CEE bonuses linked to flat roof insulation
• Local aid from the City of Paris ("Objectif 100 hectares")

For a durable green roof, waterproofing is the cornerstone of the project. Entrust this technical foundation to FDM ENERGIE, experts in flat roof waterproofing in Île-de-France.