According to the German Landscape Research, Development and Construction Society (2018) «Green Roof Guidelines – Guidelines for the planning, construction and maintenance of green roofs»
In 1969, the German government sponsored a green roof on the building. Thanks to the foam base, it has lasted quite a long time and was only renovated and improved in 1990.
Germany is the leader in Europe in terms of the intensity of “greening” roofs, with 10% of German roofs covered with grass.
The green roofs extend to the Stuttgart skyline, where municipal regulations have required the flat roofs of all new buildings to be green since 1989.