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Rigid Drainage Board 25mm

Sky Garden 25mm drainage board is a dimpled and perforated HDPE sheet for use with all green roof

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£9.85 Per SQM

(Excl. VAT £1.97)

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Total: £9.85
SKU: DRDD25 Categories: , , ,
  • A dimpled and perforated HDPE sheet (Deep-drawn recycled HDPE). A lightweight rigid drainage board with a water reservoir function, with a channelling system for the excess water produced during precipitation events. For use on extensive green roofs with a single or multi-layer construction and under path surfaces with a minimum 60 mm substrate. Also suitable for inverted roofs.

    • Suitable for use on Extensive and Intensive Green roof, Podium and Inverted Roof Systems
    • Functional in Sedum, Wildflower and Biodiverse Systems
    • Scientifically proven to provide drainage and water storage.
    • Resistant to root penetration
    • Highly resistant to acids and alkalis

    Don’t forget to order filter fleece separately for this product!

    Features and benefits

    All Green Roofs

    Suitable for use on all green roof systems and Podium systems.


    Provides drainage, water storage and filtration.

    Geo Textile

    Butted together with geo-textile filter fleece overlapping abutments.


    Resistant to root penetration and to chemicals.

  • Physical Properties Composition HDPE
    Physical Properties Thickness at 2kPa (EN ISO 9863-1) 25mm
    Physical Properties Colour Black
    Physical Properties Unit Supplied Sheets
    Physical Properties Unit Width 1m
    Physical Properties Unit Length 1m
    Physical Properties Sheet Weight 1.35kg
    Technical Properties Compressive Strength (kPa) 200 EN ISO 25619-2
    Technical Properties Filling Volume (Small naps facing up (Surface Side)) 14.5L
    Technical Properties Filling Volume (Large naps facing up (Greening Side)) 7.5L
    Technical Properties Water Permeability (l/m².s) 100 EN ISO 11058
    Technical Properties Apparent opening size (µm) 80 EN ISO 12956
  • All your materials arrive in one delivery from our UK farm and are simple to unload and install straight away.

  • Popular FAQs

    • Can I still have solar panels?
      Yes. Green roofs can be designed to fit around solar panels or the panels can fit on top of the roof. This can not only increase the efficiency of the solar panels, but the shade created by the solar panels can increase biodiversity of the underlying green roof. Special care must be taken when selecting plants to be installed in the shaded areas to ensure they grow well in low light conditions.
    • Do I need planning permission?
      Most green roofs can be installed with no planning permission, however some do require it. This depends on the location, type of building, height etc and should be consulted before installation. Green roofs are increasingly mandatory for new developments. Planning consent can stipulate that the area must blend into the surrounding landscape or mimic the water runoff of nearby Greenfield sites. Green roofs can allow constructors to overcome these terms.
    • Can I choose what plants to have?
      Sky Garden’s seed and blanket mixes have been specifically designed to work well on green roofs. The thin, low nutrient substrate and exposure can make it hard for some plants to grow well. However we do offer bespoke plants and systems, especially on intensive green roofs. For a full quote and design brief for a bespoke system please contact our sales team.
    • Do I need to water my green roof?
      Sedum is used because it is drought resistant and very hardy. Under normal circumstances the roof should not need regular watering. However, live material must be irrigated immediately following installation. This irrigation must continue in the first few months following installation and again in especially hot and dry periods. Sky Garden recommends full saturation of the system once a week in these periods.
    • How much does a green roof cost?
      Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.
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    Company Brochure

    A comprehensive guide to Sky Garden's green roof systems. Download for detailed information regarding each system available, as well as valuable guidance for maintaining your perfect green roof.

    Download Company Brochure

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