Stormwater control problem?

StormCap™ Detain 3° manages stormwater on the roof by providing retention and detention. StormCap™ Detain 3°  ingeniously detains water through a low-flow drainage layer making it a full-fledged stormwater tool ready to face second day and extra-large storms. Temporary roof storage reduces or eliminates the need for bulky storage tanks or bioretention facilities and frees up valuable ground-level space for income-generating development. Even on low-slope roofs of up to 3, StormCap™ Detain 3° performs efficiently!

Try this innovative solution.

What to do with all that space?

  • Park cars
  • Bicycle storage
  • Build a fitness centre
  • Open a coffee shop
  • Childcare space
  • More!

Download StormCap™ Detain 3° Brochure

Download Brochure
Product Code Product Name Metric 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 25.00 21.65 35.28 13.63
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 66.04 131.09 65.05

Video How it Works


How StormCap™ Detain 3° Compares


• Retention



All green roofs provide retention. Water only leaves as vapor taking about one to two weeks to fully dry out through evapotranspiration.


• Retention

• Enhanced Retention 


Incorporates needled mineral wool for enhanced retention. The rest of the water runs off, particularly in large storms and second-day storms.

StormCap™ Detain 3°

• Retention

• Enhanced Retention 

• Detention

Manages heavy rain events that are typically controlled by tanks or ponds. Incorporates a surface roughness layer that helps fill macropores in growing media, and slowly empties afterward

Is StormCap™ Detain 3° a good fit for your project?

Space constraints?


If you have a stormwater detention requirement and a space constraint, Storm cap™ Detain 3° could be a good fit. Stormwater detention with tanks or ponds consume valuable real estate, often parking garage space. StormCap™ Detain 3° can shrink or potentially eliminate tanks or ponds by detaining water on the roof. By using the roof for stormwater detention, costly underground utility conflicts can be avoided.

Green roof already in design?


If a green roof is already being designed to fulfil a mandate or a retention requirement, StormCap™ Detain 3° could be a good fit. A tank or pond is likely required for stormwater detention anyhow so upgrading the green roof to a StormCap™ Detain 3° green roof system will help reduce (or potentially eliminate) the tank or pond, for a total cost savings. Freeing up valuable real estate is icing on the cake.

Suburban? Rural?

As StormCap™ Detain 3° is ideal for buildings with space constraints, or where green roofs are already planned or required. The abundance of space in suburbs or rural areas allows for spacious ponds or tanks – in this case, the more economical solution.

Other Benefits?

  • Provides better plant performance: StormCap™ retains almost double the water of traditional green roofs, and StormCap™ Detain 3° retains about 10-20% more than that! This increases water availabilty for better plant performance.
  • Achieves sustainability goals: StormCap™ Detain 3° is a great way for companies or buildings to show commitment to the environment.
  • Increases real estate values: Green roofs provide usable or visible amenity space that increases rents and real estate value. StormCap™ Detain 3° further increases real estate value by freeing up land
  • Offers greater cooling benefits: All green roofs help cool the building, but StormCap™ and StormCap™ Detain 3° improve cooling by providing more water for evaporative heat loss.
  • Extends roof lifespan: Green roofs buffer the roofing membrane from thermal flux. StormCap™ and StormCap™ Detain 3° do an even better job of this for the same reason that cooling benefits are greater.


Read Construction Canada Technical Article to Learn How Other Technologies Compare

Download Article

 Get started. Contact or call (416) 637-5772 Ext 1

Back to Top