NBS Source


Mixed pre-grown wildflower and sedum plugs or pre-grown wildflower and sedum blanket. Install GM40 Biodiverse Substrate medium on either Radmat D25 or D40 drainage/reservoir board covered with G11 filter fleece in accordance with the Radmat specification.


Radmat GM40 Biodiverse Substrate provides a suitable growing medium to create a habitat in synchronisation with the surrounding local area, offering ideal conditions for invertebrates, animal species, colonisation by airborne plants and/ or the majority of species used in biodiverse green roofing applications including ‘brown’ roofs.

Consisting of recycled 14-5 mm crushed brick, 4-10 mm lightweight clay aggregate fine grade pine bark and composted recycled material (certified to PAS 100) all the materials used within its manufacture are responsibly sourced recycled materials of origin within the United Kingdom.

100% recycled material free from phytotoxic contaminants, all components are sourced with a strict identifiable provenance within a fifty mile radius of the manufacturing site, ensuring no contamination from invasive plant species such as Japanese Knotweed or Himalayan Balsam.

General information




Uniclass 2015

Pr_45_31_89_35 Green roof substratesPrimary

Specification data - Green roof substrates Enhanced data

General requirements

Topsoil, growing medium, subsoil and preparation materials generally

pH (range)


Air content at maximum water holding capacity


Product Reference

MedO GM40 Biodiverse Substrate



Environmental information

Country of material origin

United Kingdom

Country of product manufacture

United Kingdom

Recycled content


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