In a green flat roof with a traditional arrangement of layers, the waterproofing consists of two types of heat-weldable roofing felt. The bottom layer is roofing felt with a polyester insert. The top layer is made of roofing felt with a copper tape insert 0,1 mm, protecting the seal against perforation due to root penetration.
The filtering layer and the top vegetation layer for plants are made similarly to the inverted roof.
A green flat roof is a complex system of many elements, each of which is exposed to the adverse effects of many factors: water, organic acids, mushrooms, chemicals and fertilizers, root overgrowth, compression etc. Green flat roofs are most often made as system solutions, i.e. designed and manufactured down to the smallest detail by one manufacturer.
Green flat roofs are most often a fragment of a terrace roof available to building users. Therefore, the top vegetation layer with vegetation, it is in contact with other types of finishing and elements of street furniture. The widest possibilities of design solutions are offered by flat roofs with an inverted arrangement of layers.
• Along the attic walls and walls of the building extending above the level of the flat roof, there is a gravel band approx. 50 cm (drainage layer raised by the thickness of the vegetation layer)
• Reinforced concrete boxes allow the use of higher ones, rooted shrubs without the need to increase the thickness of the topsoil layer and perform difficult protection against root penetration.
• Concrete slabs jointed with sand on a bedding of fine gravel or coarse sand with the thickness of the vegetation layer are separated from the parts with vegetation by a concrete curb.