Extensive green roofs are vegetated with plants that develop themselves, such as mosses, sedum, herbs and grasses. The plants remain low and cover the ground. Extensive green roofs are not suitable for intensive use. They can only be walked on for inspection or maintenance work.
Attributes of extensive green roofs are:
- Minimal maintenance (on average twice a year)
- Extensive green roofs are easy to install and can be fitted at a low built height (from 70 mm)
- The loading on the roof is low: from 30 kg/m² including planting
- The planting is highly resistant to weather conditions, such as sun, wind and drought
- The vegetation places few demands on the substrate
- The plants need virtually no water or nutrition
- The costs are low, both for installation and for maintenance.
The Nophadrain Extensive Green system provides for an extra water reservoir and, thanks to the plastic drainage system, is light in weight (on average 15 kg/m2 per cm built height).
The Nophadrain Extensive Green system is built up as follows:
- Extensive vegetation
- ND DGS-E Growing Medium Extensive
- ND 4+1 high/5+1 drainage composite
- ND WSB-50 root-resistant membrane
- Waterproofing membrane
- Roof construction