Extensive
Extensive green roofs have a shallow substrate and are generally cheapest to install. They have the lightest weight and as such are generally the most favoured option for retrofitting a living roof onto an existing building.
Extensive green roofs are commonly planted with sedums, mosses and grasses that are able to thrive in a shallow substrate and require minimal maintenance and irrigation.
The key features of an
extensive green roof are...
| Substrate | 20mm-150mm |
| Vegetation | grasses, succulents, mosses |
| Cost | low |
| Structural loading | light, generally suitable for retrofit |
| Maintenance | low |
School of Engineering, University of Auckland, NZ
