The TerraExt is a traditional, pre-grown system that uses a low maintenance sedum planting rolled on top of 100 mm of a proprietary blend of extensive engineered growing medium. Plants are grown on a “blanket” and harvested like sod. Provides excellent instant green with 85% foliar coverage upon installation. Helps reduce water evaporation, soil erosion and weed growth. The growing medium is contained by a filter fabric laid above the rest of the system’s under layers. Most components come in rolls that are easy to transport and install.
Product Code Product Name Thickness (mm) Dry Wt. (kg/m2) Sat. Wt. (kg/m2) Water ret. (l/m2)
NL718 Sedum Blanket 20.00 17.20 29.70 12.50
NL600 Growing Medium 100.00 86.60 141.10 54.50
NL400 Filter Fabric 0.55 0.10 0.40 0.30
NL300 Drainage Mat 17.00 0.34 0.34 0.00
NL120 Root Barrier 0.50 0.46 0.46 0.00
Total 138.05 104.70 172.00 67.30


Increased Biodiversity with BioBerm™ and Custom Plants

Next Level Stormwater Management’s BioBerm™  offers a seamless integration of extensive and intensive green roof features: pre-grown sedum groundcover and a custom planting option. Varying depths of engineered growing medium create topographic variation and increased biodiversity. Flexible sedum mat drapes over the undulating roofscape helping reduce water evaporation, soil erosion and weed growth. Innovative for providing an enhanced aesthetic in a custom manner, over areas that are highly visible or that do not have strict weight restriction.

Unique Design & Logo Creation

Next Level Stormwater Management’s systems easily adapt and conform to various roofs. The sedum blanket and premium base layers are fully customizable and can be easily cut to fit any shape and design.


The roof membrane is located on top of the insulation and therefore subject to destructive elements such as ultraviolet degradation, thermal cycling, hailstone impact, and other environmental hazards. The vegetated system is loose-laid on a CRA which helps to protect and extend the lifespan of the roofing membrane.


Insulation is located above the roofing membrane. A root barrier is installed in between the insulation and roofing membrane to promote open diffusion and ensure the top surface of the insulation has a ventilating air space. The roofing ballast above the insulation becomes part of the system and acts like the drainage layer. Contact us for other roofing assemblies.

PMR XF300 Standard_together


Next Level Stormwater Management provides a Survivability Report with details about the success of our projects to assist with permit processes, such as the City of Toronto permit application.    For more info, or help with other municipalities, please contact us.


to CAN/CSA A123.24

Next Level Stormwater Management was a key participant in developing the Canadian Standard Test Method for Wind Resistance of Modular Vegetated Roof Assembly – the first such test in the world. Contact us for more info.

Technical Document Downloads

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