StormCap™ Detain 3°
StormCap™ Detain 3°
Retain and Detain

Key features
Retention & Detention
- Maximum SWM potential by combining retention & detention
- Retention – water is stored in Hydro Blanket & growing medium
- Detention – runoff is slowed down through friction at drainage level
- Optional reservoir cell can further detain up to 100 mm (4″) of water
- System is customized to meet project-specific SWM requirements
- Ideal for projects with stringent & challenging SWM requirements
Properties
Product Code | Product Name | Thickness (mm) | Dry Weight (kg/m2) | Saturated Weight (kg/m2) | Water Retention (l/m2) |
---|---|---|---|---|---|
NL718 | Sedum Blanket | 20.00 | 17.20 | 29.70 | 12.50 |
NL600 | Growing Medium | 50.00 | 40.50 | 70.00 | 29.50 |
NL501 | NM Hydro Blanket | 25.80 | 3.90 | 28.80 | 24.90 |
NL351 | Reservoir Cell | 12.70 | 0.78 | 0.78 | 0.00 |
NL350 | Detention Mat | 5.00 | 0.40 | 0.80 | 0.40 |
NL120 | Root Barrier | 0.50 | 0.46 | 0.46 | 0.00 |
Total | 114.00 | 63.24 | 130.54 | 67.30 |
Product Code | Product Name | Thickness (inch) | Dry Weight (lb/f2) | Saturated Weight ((lb/f2)) | Water Retention (inch) |
---|---|---|---|---|---|
NL718 | Sedum Blanket | 0.79 | 3.52 | 6.08 | 0.49 |
NL600 | Growing Medium | 1.97 | 8.30 | 14.34 | 1.16 |
NL501 | NM Hydro Blanket | 1.02 | 0.80 | 5.90 | 0.98 |
NL351 | Reservoir Cell | 0.50 | 0.16 | 0.16 | 0.00 |
NL350 | Detention Mat | 0.20 | 0.08 | 0.16 | 0.02 |
NL120 | Root Barrier | 0.02 | 0.09 | 0.09 | 0.00 |
4.49 | 12.96 | 26.74 | 2.65 |
Stormwater Retention

Stormwater Retention
- Water is stored on the roof & does not reach the storm sewer
- Source control reduces the burden on the city’s storm sewers
- Retained water reduces plant stress & irrigation needs
Stormwater Detention

Stormwater Detention
- Detention reduces & delays peak flow, which helps prevent flash floods
- Unlike blue roofs, friction detention works efficiently on low-sloped roofs
- Detention is reliable & works well with back-to-back storms
Climate Resilience

Climate Resilience
- Futureproof – manages intense/frequent rainfalls due to climate change
- High water storage to reduce plant stress between rainfall events
- Improves water storage & thermal performance of the building
Works on Sloped Roofs
StormCap™ Detain 3° easily adapts and conforms to various roof designs. The sedum blanket and premium base layers are fully customizable and can be easily cut to fit any shape and design.
BioBerm™ & Biodiversity
StormCap+Detention™ and the Bioberm ™ add-on feature seamlessly integrate for topographic variation and enhanced biodiversity. The flexible sedum mat drapes over varying depths of engineered growing medium creating an undulating roof scape with custom plants.
Technical Document Downloads

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In-Person Presentations or Live Webinars
Engineering Green Roofs for CoV’s Rainwater Management Plan
Green roofs play a key role in the City of Vancouver’s (CoV) new simplified rainwater management (RWM) requirements for new Part 3 buildings that took effect on Jan 1. We will learn how to design green roofs to help meet CoV’s retention/detention requirements and when upgrading to a blue-green roof can increase ROI.
Engineering Green Roof Systems to Optimize SWM 2.0
2.0 is a deep dive into the latest stormwater retention and detention technologies. Learn to use modeling to meet water balance and quantity control targets through initial abstraction and irrigation water reuse. Recognize opportunities and limitations. Case study demonstrates performance and cost savings.
Strategies to Meet Policy & Design Goals in Toronto
Check off multiple requirements set by the Toronto Green Standard (TGS) & Wet Weather Flow Management Guidelines (WWFMG). Success requires collaboration between architect, landscape architect & engineers, as well as understanding components, their functions & selection criterion to achieve specific goals.
NutsN’Bolts: A-Z of Essential Tips to Achieve Success
This three part series navigates through the complete green roof process; from recognizing opportunities, to planning, to material selection and system design with emphasis on stormwater management, to specifications and drawings, to clarity in construction documents and, finally green roof aftercare and maintenance for long term success. (3 hours over 3 weeks)
Cost Saving Strategies to Meet Toronto’s Green Roof Policy
Love ’em or hate ’em green roofs are everywhere and can check off multiple requirements set out by the Toronto Green Standard (TGS) and the Wet Weather Flow Management Guidelines (WWFMG). This webinar explores functions and selection criterion, and the collaboration between architect, landscape architect and engineer to achieve specific design goals.
Wind Design for Modular Vegetated Roof Assemblies
Webinar about the CSA A123.24: Standard Test Method for the Wind Resistance of Modular Vegetated Roof Assembly (VRA) reviews the two key test components that measure wind uplift and wind flow resistances. Videos & case studies help demonstrate how VRAs behave at different wind pressures and wind speeds.