Once upon a time...
If the greening of roofs is something that is found in numerous societies, as we explain below, the same goes for the greening of walls, the use of walls to grow food (vines in particular) being an ancient tradition. With the development of modern technologies (in terms of materials, types of substrates and ways of fixing them vertically, watering techniques) the greening of walls for aesthetic reasons has become an extremely popular feature of both exterior and interior architecture.
Many of Adivet's members operate on this market, and logically the association also covers this technique. This section will soon reflect its importance.
Vegetation long a feature on roofs
The principle of installing plants on roofs is not new: we have all heard of the "Hanging Gardens of Babylon" and we have all seen trees on roofs, as part of "gardens in the air". Those of us who have had the opportunity to visit Scandinavia will sometimes have seen some much surprising examples of traditional houses, with double pitched roofs ... covered in turf; this is what is known as the "Norwegian chalet".
In other traditional societies, in Turkey or Mongolia, or certain Amerindian tribes, the presence, deliberate or accepted, of vegetation on roofs is normal, as it helps to keep interiors cool in summer. And don't forget the thatched cottages in Normandy with irises planted on the roofs…
In 20th century architecture, the roof garden roof has gradually become one of the solutions enabling city-dwellers to maintain a connection with nature. The technical elemnts making up this solution started to be improved in the 1970s, with the arrival on the market of lightweight, root-resistant waterproofing membranes and lightweight compost mixtures.
In the middle of the 80s, an innovative new solution saw the light of day in Germany: so-called "extensive roof greening", which caught on very fast in Germany, then in the surrounding countries (with the notable exception of France). By the mid-90s, almost 15% of newly created flat roofs in Germany were green roofs, mainly using this method. This remarkable success was made possible by the support provided by the public authorities (grants given by the Länder and cities in particular) and the adoption of an environmental mindset in German society.
In France, the concept of extensive green roofing made its appearance at the beginning of the 90s, under the impetus of waterproofing manufacturers. It developed very slowly during the 90s, but has been more and more in line with the expectations of French society since 2004, particularly because of the HQE scheme and a concern to take account of environmentally friendly solutions in construction (sustainable development).
In 2007, the second edition of the professional rules for the design and construction of green roofs was co-produced by the Adivet, the CSFE, the UNEP and the SNPPA.