Blackdown Extensive Green Roof

Alumasc Extensive


Blackdown extensive green roofs are lightweight with a relatively shallow substrate, providing a versatile range of planting generally comprising of drought tolerant succulents such as sedum, rockery and alpine plants.


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Key Features & Applications

extensive roof garden

  • Blackdown extensive green roofs are suitable for lightweight roof decks, inaccessible roofs, flat or sloping roofs and are equally suited to re-roofing or new build projects
  • They are versatile, economic and can provide ecological and economic benefits. Their incorporation on the roof can result in reduced water run-off
  • Blackdown green roofs comply with the UK’s GRO Green Roof Code of Best Practice 2011 and the German Landscaping and Landscape Development Research Facility (FLL) Guidelines

Design, Planting & Waterproofing

  • Extensive green roofs have a typical build-up height of 100mm (including drainage layers) and do not normally require irrigation once they are established
  • Planting options include Naturemat, plug plants or sedum cuttings and typically consists of sedums inlcuding alpine and rockery plants. Sedum-type plants are self-sustaining and wind, frost and drought resistant
  • Variation within the system can be achieved by using different substrate formulations and depths to support rockery and alpine plants
  • Waterproofing options include Derbigum membranes, Euroroof Mastergold membranes, Hydrotech structural waterproofing and standing seam roofing 

Installation & Maintenance

  • Blackdown green roofs can be installed by the Blackdown in-house contracts division or by Alumasc's nationwide network of Registered Contractors
  • Blackdown extensive green roofs are easy to install, do not require a permanent irrigation system and need minimal maintenance
  • Warranties are available for the Alumasc waterproofing system used in the green roof build up 

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White House Works, Bold Road, Sutton, St Helens, Merseyside, WA9 4JG