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Retention Roof Flow Control Extensive and Semi-Intensive

Better microclimate, rainwater retention and reduced runoff from green roofs

A green roof provides a better microclimate. Our green roof system RETENTION ROOF FLOW CONTROL also keeps the water in the cities and helps to store it there. This turns the city into a sponge. Water is stored when it is in abundance so that it is available when it is urgently needed.

And this is exactly what is meant by the sponge city concept. Here, green roofs and rainwater management work together effectively and sustainably. They are an important instrument on the way to the sponge city of the future. In short: they are indispensable in the fight against the consequences of climate change.

The RETENTION ROOF FLOW CONTROL is particularly recommended for extensive green roofs with special structural requirements. The water retention box (WRB) is used as a retention and drainage element. The WRB element can be used flexibly. Depending on requirements, it can be used as a permanent water reservoir and/or as a temporary retention area to delay runoff.

The RETENTION ROOF FLOW CONTROL for extensive and simply intensive green roofs is economical and sustainable. It ensures efficient rainwater retention and delays runoff. The WRB 80F has an integrated permanent water storage tank of 6 l/m², which is independent of the throttle. The WRB 80F can be stacked inside each other and is therefore particularly easy to transport.
The RETENTION ROOF FLOW CONTROL is a mitigation measure within the framework of the impact compensation regulation and meets the requirements of the FLL Green Roof Guidelines.

Ecological value
Maintenance costs
Costs*from 47 €/m2

* Standard cost value for 1,000 m², net incl. installation, material varies from region to region.

System structure retention roof flow control extensive and semi-intensive

Note: Click on the marked points to get more information!

Perennial plants and/or Sedum sprouts with seed mix EKR

  • 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
  • learn more: Seed mix EKR
  • learn more: Sedum sprouts

Extensive Substrate E (from 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 and Capillary Fleece FIL 200K

Water Retention Box WRB 80F

  • High cavity volume for water retention
  • Water retention adjustable to the green roof build-up above
  • Low weight
  • High water storage capacity
  • Stackable for easy transport
  • With capillary columns
  • learn more: Water Retention Box WRB 80F

Protection and Storage Fleece RMS 300

Complementary products

  • included in the rendering
  • inserted into the water retention box
  • ensures the transportation of the accumulated rainwater to the substrate level

Technical specifications

Weightfrom 100 kg/m² or 1.0 kN/m²
Build-up depthfrom 140 mm
Roof pitch0°
Vegetation formsedum-herbs-grasses
Discharge coefficientProject specific settings possible
Retention volume72 l/m² (WRB 80F)
Water storageapprox. 110 l/m²

Optigrün Retention roofs win the PLUS X AWARD

Optigrün international AG is the proud winner of the PLUS X AWARD, the world's largest innovation award for technology, sports, and lifestyle. It honors brands for the quality and innovative edge of their products. The award is presented by an independent, international jury of experts.

Optigrün retention roofs impressed in 5 out of 7 categories and were awarded seals of approval for Innovation, High Quality, Ease of Use, Functionality and Ecology. These serve as a guide for customers and retailers when making purchases, stand for outstanding product features, and help to quickly and clearly recognize the added value of an award-winning product over the competition.