Modular Green Roofs

SIG Design & Technology’s modular green roofs provides a fast effective method of creating a sedum based green roof without the need for specialist installation knowledge or tools. Providing an instant green roof each module arrives with a minimum coverage of 80% to achieve the best possible vegetation layer.

SIG’s modular green roof allows for the natural sharing of water, nutrients and beneficial organisms across the entire rooftop strata.  It also minimises hot, wet and dry zones, and avoids compartmentalising the growing medium. The module comprises four layers – drainage, filter, substrate and sedum.

Drainage layer: The excess water that cannot be absorbed by the cassette can be easily discharged through the drainage system. The water storage layer contains four drainage holes on the top and bottom of each cavity. Rainwater is buffered through a capillary layer of crushed clay grain. Excess water that cannot be buffered will drain slowly. To create an additional buffer for droughts, the cassette is equipped to store about 1 cm of noncapillary water at the very bottom.

Filter layer: A non-woven polyester filter membrane of 150gsm ensures that the fine particles of the substrate cannot be washed away and cannot block the drainage holes.

Substrate layer: The thickness of the substrate layer has been adapted to the needs of the sedum species and to the climate. This layer, on one hand, provides nutrients and water supply for the vegetation, and on the other hand it provides oxygen and anchorage for the roots. The substrate is light weight, providing nutrition, aeration and a high capacity to store water.

Sedum layer: The modules are supplied with a minimum coverage of 80%. To achieve the best possible vegetation layer, 8 to 10 different species are used. The sedum is sprouted and well rooted.

Waterproofing: Once the roof is fully waterproofed follow the manufacturer’s compliance directions for protection of the waterproofing. A 300gsm fleece can be applied directly on top of the waterproofing layer.


  • A pre-grown interlocking plant module that offers ease of installation with exceptional sedum growth coverage
  • Delivered in palletised form with a maximum number of 66 modules per pallet (15 m2)
  • Lightweight with a high water storage capacity
  • 8 to10 different sedum species are well rooted and grown to maturity Module dimensions: 450mm (L) x 495 (W) x 80mm (H)
  • Coverage : 4.4 modules per m2
  • Dry weight of module: 8.0kg
  • Dry weight per m2: 35.2kg
  • Saturated weight of module: 12.00kg
  • Saturated weight per m2: 52.80kg

More Information

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