LIGHTWEIGHT ROOF
The slim green roof structure for roofs with low static reserves (0-5°)
With the LIGHTWEIGHT ROOF , roofs can be greened if their statics only allow a low load. Even when saturated with water, LIGHTWEIGHT ROOF weighs only around 55 kg/m² and is therefore significantly lighter than an average gravel roof with a 50 mm structure. The slim green roof structure is ideal for renovating older roofs without structural reserves and for large industrial roofs, for example.
The LIGHTWEIGHT ROOF system can generally be used on flat roofs with fixed waterproofing. Inverted roofs are unsuitable for the lightweight roof.
The lightweight substrate L exceeds the requirements of the FLL Green Roof Guidelines for extensive single-layer substrates.
The LIGHTWEIGHT ROOF system is suitable for 0-5° roofs and is drained via a solid drainage system (FKD).
| Ecological value |  |
| Maintenance costs |  |
| Costs* | from 44€/m² |
* Standard cost value for 1,000 m², net incl. installation, material varies from region to region.
System structure lightweight roof
Note: Click on the marked points to get more information!
Vegetation mat
- Pre-cultivated sedum mat for the rapid establishment of vegetation in order to prevent wind erosion, with decomposable carrier.
- learn more: Vegetation mat
Low Density Substrate L (30 l/m²)
- Specially formulated substrate for single layer extensive roofs featuring low weight but high water storage capacity.
- learn more: Low Density Substrate L
Drainage and Storage Board FKD 25 (25 mm)
- Rapid discharge of surplus water
- Prevents accumulation of water for non-pitched roofs and large drainage lengths
- Light-weight build-up with high drainage capacity
- learn more: Dainage and Storage Board FKD 25
Protection and Storage Fleece RMS 300
- Protects the roof membrane against damage and stores water
- For inverted roofs, use the Optigrün Trickle Protection Fleece RSV 120 instead of the RMS Fleece
- learn more: Protection and Storage Fleece RMS 300
Complementary products
- Not included in the rendering
- Enables easy control of the roof drains
- Installation on the drainage and water storage element FKD 25
- learn more: Inspection Chamber FSA 40L
Technical specifications
| Weight* | from 55 kg/m² or 0.55 kN/m² |
| Build-up depth | from 60 mm |
| Roof pitch | 0-5° |
| Vegetation form | moss-sedum |
| Water retention | 40-50 %/year |
| Discharge coefficient** | Cs = 0.5-0.6 |
| Water storage | approx. 18 l/m² |
* Weight specifications refer to saturated conditions; dry weight is approximately 60 - 70 % of the saturated weight.
** In accordance with the current FLL Green Roof Guidelines.
Downloads
- CAD-Drawing (pdf) 2 MB
- CAD-Drawing (dwg) 3 MB