Platon DE 40 sheets are intended to be used as a drainage layer on low-slope green roofs with an inclination of 1:10 or milder. The sheets are recommended for sites with high drainage requirements, such as roof gardens with thick substrate layers. The sheets store irrigation water in integrated chambers linked together via overflow channels. The extensive drainage layer formed below the sheets provides high drainage for excess water. Platon DE 40 sheets discharge the stored water over a long period of time, ensuring optimal distribution of water to the vegetation layer.

  • Stores and drains water in high-demand applications
  • Decreases the need for watering during dry periods
  • Removes excess water efficiently
  • Efficient protection for the waterproofing


The structure below the sheet must always include waterproofing and root barrier provided by, for example, Kerabit modified bitumen membranes with a layer of Kerabit Root Prevention Membrane on top. In inverted structures, Platon DE 40 is installed on top of thermal insulation, such as XPS.

Manufacturer / Manufactured for Isola AS, Norway
Country of origin Norway
Conformity marking CE
Production material HDPE
Structural height 40 mm
Nominal thickness 2 mm
Dimensions 1,29 x 2,23 m
Nominal weight 1900 g/m²
Colours black
Water reservoir 10 l/m²
Drainage capacity 3.85 l/sm between studs at 2% slope, gaps (permeability) 0.7 l/sm²
Other considerations for roofs with inclination of 1:10 or milder

The sheets are installed with one overlapping row of chambers so that the drainage outlets remain in line with the direction of water flow (at an angle to the direction of the slope) with the bottoms of the studs down. A filter fabric, e.g. N2/KL2, is installed on top of the sheet as a separation and filtering layer. If necessary, a protective layer or filter fabric is also installed below the sheet to protect the waterproofing or thermal insulation in case of inverted structures.

Installation should be carried out in calm weather to allow safe lifting of the materials without lighter materials being blown down the roof by the wind. The sheets should be covered with filter fabric and substrate as soon as possible.