the green roof market | France

1.1 Definition and scope of the study

The greening of a roof or Horizontal Vegetated Complex Wall (known as "HVCW") can be defined as the installation of a set of materials and plants composing a microflora with a water drainage system. The installation of green roofs is more adapted for new buildings, however the greening of existing roofs is possible. Shis installation must be compatible with the existing structure of the roof (slab...) and the existing materials (concrete, wood...). The technique was developed in architecture in the 1970s mainly in Scandinavian countries, Germany, Switzerland and more recently in France and Belgium in the 1990s and 2000s.

A green roof is composed of several superimposed layers:

• A supporting structure
• A vapour barrier
• An insulating layer
• A drainage and filtration layer with an anti-root surface
• A substrate
• A vegetation

According to the French Chamber of Waterproofing (CSFE), green roofs have much better waterproofing qualities than traditional roofs, thusincreasing durability (heat reduction, water filtration, pollution control, etc.) this technique was developed in architecture in the 1970s, mainly in Scandinavian countries, Germany, Switzerland and more recently in France and Belgium in the 1990s and 2000s.

The global green roof market has been growing strongly since 2014, dominated by the North American market followed by the European and then the Asian market and driven by the construction and urbanization policies of major metropolises.

The French green roof market is dynamic although it lags relatively behind neighbors such as Germany and therefore has significant growth potential.

The demand is still largely public, especially in cities, in relation to commercial or residential areas. The legislative and fiscal framework also plays an important role in stimulating and encouraging the installation of green roofs.

More than the search for a particular aesthetic,innovation is key in this market. Green roofs are constantly improving their environmental performance, whether in terms of their thermal and sound insulation potential, rainwater management or their impact on biodiversity. Green roofs are also prime locations for developing urban agriculture.