Icopal Drainage Board 20 FF meets the need for free drainage within any green roof

BMI Canopia FKD 20 Drainage and Storage Board

The need for free drainage within any green roof is vital to prevent the system from becoming waterlogged and to reduce excess loadings on a roof deck. 
BMI Canopia FKD 20 Drainage and Storage Board creates a 20 mm free-draining void to allow excess water to move swiftly and unhindered to the relevant roof drainage outlet.


BMI Canopia FKD 20 Drainage and Storage Board is a black, high density polyethylene (HDPE) cuspated drainage board. The board is manufactured from 100 % recycled HDPE. The drainage board has ribbed cups provide additional resistant to compression. The top surface of the drainage board is perforated to allow excess water to pass through and drain away. 

Product Code Description Size
3101081 BMI Canopia FKD 20 Drainage and Storage Board 2m x 1m x 20mm


Pack Size: LxWxH: 2m x 1m x 20mm


Recycled HDPE
Nominal thickness: Approx. 20 mm
Grammage: Approx. 900 g/m2
Colour: Black / grey

Compressive strength:

Approx. 120 kN/m2
Filling volume: Fill flush to the upper edge approx. 6.0 L/m2
Water reservoir unfilled: Approx. 5.3 L/m2
Water reservoir filled: Approx. 1.6 L/m2
Delivery weight:

Approx. 1.8 kg per panel

Approx. 925 kg per disposable pallet

Quantity / delivered unit:

2 m2 per panel ( 2 m x 1 m)

1,000 m2 per pallet

Delivery form: 500 pieces per pallet (2.05 m X 1.05 m)

Water discharge capacity: 

           Gradient Water Flow Rate
  i = 0.01 (= 1 % roof pitch): 0. 68 L/(m*s)

i = 0.0.2 (= 2 % roof pitch):

0.97 L/(m*s)
  i = 0.05 (= 5% roof pitch): 1.59 L/(m*s)
  i = 0.10 (= 10 % roof pitch): 2.29 L/(m*s)
  i = 1 (vertical): 7.62 L/(m*s)



BMI Canopia FKD 20 Drainage and Storage Board has been tested in accordance with DIN 4095: Drainage.

Intended Use

BMI Canopia FKD 20 Drainage and Storage Board is intended for use as a drainage and storage board under extensive green roofs in triple-layer structure with filter mat and extensive multi layer substrate E or directly filled with extensive single layer substrate M on flat roofs up to RP 5°(= 8.8%).

Specific Properties

  •  100% recycled HDPE.
  • Drainage according to DIN 4095.
  • Safe and targeted guiding of excess water.
  • Depositing if water in the recesses.
  • Suitable for non-pitched roofs.
  • Lightweight super structure with high drainage capacity.
  • Recyclable.

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