Partly or fully greened with plants covering the ground, the flat roof areas can bring about a noticeable improvement when it comes to the microclimate in residential areas. This results in compensation areas for soil sealing in urban areas, high-performance retention zones for heavy rain events and green oases which are able to bind large amounts of fine dust. At the company DÖRKEN, you will find adequate options for the design of your green roof. There are basically two types of green roof: the extensive and the intensive greening:
The extensive roof greening is made of natural forms of vegetation with low growth forms. The vegetation layer consists mainly of plants which rarely need to be watered and are largely insensitive to temperature. As a consequence, the extensive roof greening can be found on unused flat roofs as they only need to be accessed to once or twice a year for inspection.
If there are higher requirements in terms of quality, variety, and size of the vegetation, intensive roof greening will be used. In this context, numerous different plants, perennials, and shrubs, in individual cases even lawns and trees may find space on the flat roof. Combined with terrace areas, seating options and sidewalks, the intensive roof greening can offer a wide range of design options and recreational zones, including urban gardening. However, they have a significantly higher maintenance level and have to be regularly supplied with water and nutrients. In return, the intensive greening results in an increase of the residential value of a building, by bringing a piece of nature into densely built-up settlements and by making a lasting contribution to the improvement of the urban microclimate zones.
DELTA®-TERRAXX takes on the function of an efficient protective, filter and seepage layer for intensive greening with extensive substrate thicknesses. This feature ensures that no backwater which may be harmful to plants can form.
With DELTA®-FLORAXX TOP, the extensive flat roof greening, which is feasible without major maintenance, can be optimally implemented. The membrane can store up to seven litres water per square metre in its 20-millimetre-high knobs. This quantity of water is then available to the plants as a reserve during dry periods. The excess rainwater seeps through the perforations under the membrane to then run off between the knobs.