RETENTION ROOF MEANDER FKM 30
The inexpensive and efficient green roof to delay runoff
For extensive green roofs where a very low peak runoff coefficient is required, the RETENTION ROOF MEANDER FKM 30 is particularly suitable. With the Meander FKM 30 drainage element, the rainwater has to cover a longer flow path and is also throttled at the outlet. This ensures a significant reduction in the peak discharge coefficient.
The RETENTION ROOF MEANDER FKM 30 is an economical and efficient system for delaying runoff. The inexpensive and flat system structure is particularly interesting for large industrial roofs, for example, where it is often necessary to comply with certain discharge restrictions. The sedum vegetation we recommend is robust and requires little maintenance. This also contributes to the cost-effectiveness of this green roof system.
The RETENTION ROOF MEANDER FKM 30 is an impact mitigation measure within the framework of the impact compensation regulation. It meets the requirements of the FLL Green Roof Guidelines.
Ecological value | |
Maintenance costs | |
Costs* | from 25 €/m2 |
* Standard cost value for 1,000 m², net incl. installation, material varies from region to region.
Meander - modeled on nature
Meanders are natural river formations that result from the turbulence of water. Instead of moving exclusively along the actual current, the river forms small whirlpools that grind the bank in a round shape against the actual direction of flow. Over time, S-loops are formed in which the water moves. This increases the flow length and reduces the flow velocity.
Good green roof design is close to nature: in retention roof construction, the meander shape of the water and retention elements allows the water to be drained away more slowly. Thanks to the S-loops, the water never flows in a straight line, but on winding detours, which effectively reduces runoff peaks.
System structure retention roof Meander FKM 30
Note: Click on the marked points to get more information!
Perennial plants and/or seed mix EKR and sedum sprouts
- Proven and specially-balanced seed mix consisting of a wide range of herbs and grasses (as desired) as well as numerous types of sedum sprouts
- Perennials in roof substrate pre-cultivated
- learn more: Sedum sprouts
- learn more: Seed mix EKR
Extensive Substrate E (60 mm)
- A substrate with high water storage capacity and good air porosity, tailored to extensive multi layer systems
- learn more: Extensive Substrate E
Filter Fleece FIL 105
- Prevents fine particles from forming sludge in the drainage layer; high water permeability.
- learn more: Filter Fleece FIL 105
Meander Water Retention Board FKM 30 (30 mm)
- Delays discharge of surplus water
- Prevents accumulation of water
- Lighter build-up with better drainage performance
- Temporary water storage only
- learn more: Meander Water Retention Board FKM 30
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
- Simple control of the roof drains
- Can be raised in 100 mm steps
- Drainage openings at the side and top
- learn more: Inspection Chamber FSK 37
Technical specifications
Weight* | from 90 kg/m² or 0.90 kN/m² |
Build-up depth | from 90 mm |
Roof pitch | 0-5° |
Vegetation form | Sedum |
Water retention | 50-70 %/year |
Discharge coefficient** | Cs = 0.01 |
Discharge yield*** | approx. 19 l/m² temporary |
Water storage | 40 l/m² |
* Depending on the load capacity of the substructure, Optigrün "High Density (HD)" or "Low Density (LD)" substrates can be used. Weight specifications refer to saturated conditions; dry weight is approximately 60 - 70 % of the saturated weight. In accordance with the requirements of the FLL Green Roof Guideline, the specified weight does not take temporary water accumulation into account.
** A discharge coefficient of Cs≤0.1 should be used for the dimensioning of the drainage system. As cuts are required when laying the slabs, the test value should not be used to design the drainage system.
*** Determined according to FLL discharge coefficient measurements using a 15-minute reference rainfall r(15) = 300 l/s x ha.
Downloads
- Plant list (pdf) 407 KB
- CAD-Drawing (pdf) 1 MB
- CAD-Drawing (dwg) 2 MB