Read technical article on rooftop detention and how other technologies compare.


Stormwater control problem?

StormCap™+Detention manages stormwater on the roof by providing retention and detention, making it a full-fledged stormwater tool ready to face second day and extra-large storms. Detention provides a clear return on investment. StormCap™+Detention reduces or eliminates cisterns and bioretention facilities and frees up valuable space for income-generating development. It even works on a sloped roof!

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!

Video How it Works

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How does StormCap™+Detention work?


• 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.


• 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™+Detention a good fit for your project?

Space constraints?


If you have a stormwater detention requirement and a space constraint, StormCap™+Detention could be a good fit. Stormwater detention with tanks or ponds consume valuable real estate, often parking garage space. StormCap™+Detention 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™+Detention could be a good fit. A tank or pond is likely required for stormwater detention anyhow so upgrading the green roof to a StormCap™+Detention 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™+Detention 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™+Detention retains about 10-20% more than that! This increases water availabilty for better plant performance.
  • Achieves sustainability goals: StormCap™+Detention 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™+Detention further increases real estate value by freeing up land
  • Offers greater cooling benefits: All green roofs help cool the building, but StormCap™ and StormCap™+Detention 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™+Detention do an even better job of this for the same reason that cooling benefits are greater.

Learn more about StormCap™+Detention

Stormwater management is unique to each project. Our team will start the process and run project-specific calculations.

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Ready to find out what StormCap™+Detention can do for your project?

Stormwater management is unique for each project. The results will vary based on size, slope, design storm, max outflow rate and number of roof drains. See sample below.

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Download StormCap™+Detention Brochure

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