INTENSIVE ROOF GARDENS
Intensive roof gardens can visually be just like gardens on the ground, but building them is a little more complex.
Considering they do not form on natural terrain, the conditions for the normal growth of plants need to be created.
Roses, shrubs, ornamental grasses, trees are able to grow on the roof. It’s also possible to make any the required garden elements – fountains, ponds, paths, small walls, pergolas… Depending on the intended use of the garden or park, playgrounds can be built, rows of trees planted, sun terraces or decks can also be arranged. During the construction project for the facilities, knowing the kind of roof garden desired is necessary, to ensure the proper static loads for the desired thickness of the substrate, and to provide for the construction of such static loads (small edge walls along the roof). Hence, along with the particular construction or financial constraints, only a lack of imagination can prevent one from building a garden on a roof.
BUILDING INTENSIVE ROOF GARDENS
Sometimes it’s necessary to use modules for the superelevation in order to reduce the amount of material required, especially for hard to reach locations, or to reduce the load on the roof.
After setting the modules, which need to be properly connect to each other, filling with gravel takes place.
In areas envisaged for the cultivation of plants, where a greater substrate depth is required, instead of the modules, PVC drainage-accumulating troughs (6 cm in height) are placed which are then filled with a mineral substrate (lava granules, expanded clay), onto which filter geotextile is then placed. Substrate is then transported onto the geotextile where the thickness of the substrate depends on the type of plants to be planted (e.g. 20-30 cm for low shrubs and ground covering plants, 30-60 cm for larger bushes).
After bringing in the material, spreading it and finely levelling out the substrate (a special substrate blend is definitely required for intensive roof gardens!), this is followed by planting as required by the project. After the planting, a final layer of decorative gravel is placed on the gravel surface.
The fabrication of garden elements (water element, paths and terraces) is somewhat more complicated than for ordinary gardens, due to more difficult access and the limited height available for the structure.