This system is designed for extensive green roofs with a substrate level of between 70mm and 200mm.

The vegetation can be grass, sedum blankets, sedum/wildflower mixes, herbs or bio-diverse (brown roof) plants; depending on the wishes of the client.

Each layer or component is supplied separately in bag or roll form and installed separately as a “dry” build-up. This allows easy access to roof areas.

This system is ideal for large scale areas, unlevel or more complicated decks as it is flexible and “built into” the existing structure.

The Build-up

From the upper surface, working down:

• Vegetation – standard products either
  • grass grown from Pro-grass pre-seeded biotextile,
  • sedum blanket or
  • sedum/wildflower mix
• Growing medium/substrate at an absolute minimum of 70mm deep up
  to 200mm, containing
  • crushed lecca or crushed brick
  • green waste (up to 30%)
  • peat (10%)
  • locally sourced marine aggregate and grit
  • 12-14 month release fertilizer (if required)
• Geotextile filtration layer
• 20mm perforated Protectodrain 20P
• Geotextile filtration layer
• Wallbarn 3mm Protectoboard (where appropriate)

Grass finish

• Using Pro-grass biotextile fabric and laid into a substrate 200mm
• Can tolerate higher level of traffic
• Grass takes approximately 4 weeks to grow and is fully established after 4 months
• Less rainwater runoff (up to 60% retained)
• Regular maintenance and irrigation required
• Saturated weight up to 150kg per m2

Sedum blanket

• 70mm substrate
• Sedum supplied in established (9 month old) blanket
• Instant green roof
• Very low maintenance, weed clearance once per year
• Drought resistant, little irrigation required
• Saturated weight approximately 50kg per m2

SEE OUR CASE STUDY HERE

Sedum/wildflower blanket

• 70mm substrate
• Plug planted mixture and established into thin layer of substrate.
• Native, local plants can be used including herbs, bulbs and heather
• Can take up to 24 months to be fully established
• Fairly low maintenance depending on vegetation
• Saturated weight approximately 50kg per m2

Brown roofs

• 70mm substrate
• A basic sedum / wildflower blanket supplied interspersed with native, local plants
• Natural, sustainable habitat can be created
• Very low maintenance and no irrigation required
• Opportunities to recycle site waste in substrate

Plug planted extensive roofs

• Up to 200mm substrate
• Plug planted vegetation installed on site
• Large variety of foliage available
• Very low lead times
• Can be installed at any time of year
• Can take up to 24 months to be fully established
• Less rainwater runoff (up to 60% retained)
• Higher maintenance
• Saturated weight up to 200kg per m2 depending on vegetation

To see the guidelines for material selection, uses, installation and planting times please download the green roof system brochure (pdf).