Blue Green Roof Solutions for Stormwater Management
RoofBlue is LiveRoof’s patented, effective, and sustainable solution for stormwater management. Each of our RoofBlue products is designed to enhance storm water capture in its own, distinctive way. Read more about how our blue and blue/green roof products work below.
RoofBlue® RETAIN™
Now Patented!
RoofBlue RETAIN™ is a true “Cradle-to-Cradle” solution for enhanced storm water capture. It captures and retains storm water. Then, after the storm event, it transfers storm water upward to the plant roots, for plant growth and transpiration (to the atmosphere).
ELEGANTLY SIMPLE & EFFECTIVE
RoofBlue RETAIN™ follows years of development and testing, is supported by university research, and outperformed a typical mineral wool storm water retention product.
SUSTAINABLE
Compared to mineral wool (which has a large carbon footprint and can pose disposal challenges), RoofBlue RETAIN™ is made from recycled material and is recyclable itself. It could be repurposed 100 years from now.
For more information, please contact any of our dedicated LiveRoof Growers in your area. We are here to help.
See how RoofBlue helps protect water resources:
WHITE PAPER
Read our official white paper on RoofBlue RETAIN™‘s effectiveness in enhancing plant growth and reducing irrigation requirements on a green roof.
STORMWATER CAPTURE RESEARCH
Brad Rowe, green roof researcher and MSU Department of Horticulture professor, had a study published in 2022 in which he compares RoofBlue RETAIN™ to various other methods of storm water capture.
PLANT GROWTH & IRRIGATION RESEARCH
We tested the irrigation needs and plant growth comparing RoofBlue® RETAIN™ to a standard hybrid module and found significant water savings and plant growth in the RETAIN™ modules.
ROOFBLUE RETAIN™ IN THE LAM
RoofBlue RETAIN™ was featured in the Living Architecture Monitor’s latest research article. Check it out!
RoofBlue® DETAIN
The LiveRoof Integrated RoofBlue® DETAIN is engineered to provide temporary water detention underneath all LiveRoof systems. When used with control flow drains, RoofBlue expands the usefulness of a green roof system as a stormwater management tool. RoofBlue can do the following:
ROOFBLUE FAQ
Yes! World-renowned green roof researcher, Brad Rowe, published a study in 2022 that compares the stormwater retention effectiveness of several green roof, blue roof, and blue-green roof systems & methods.
Additional research by Dr. Anna Droz tests RoofBlue RETAIN™ ‘s effects on plant growth and irrigation needs. Results show significant water savings and increased plant growth in the RETAIN™ modules.
A blue roof is designed to slow or store stormwater runoff, easing the burden on the stormwater systems. When combined with the LiveRoof® brand green roof system—which in itself is an effective stormwater tool—the RoofBlue system maximizes rooftop stormwater management capability. This may greatly reduce the need for other onsite stormwater management tools, such as cisterns, detention ponds, or underground storage tanks.
LiveRoof systems are compatible with nearly all waterproofing types: EPDM, TPO, PVC, bituminous, polyurethan, rubberized asphalt, inverted or conventional. Some green roof system providers form alliances to leverage sales. We don’t believe in playing such games as our goal is to provide the best quality green roofs on the market and make them available to all. In keeping with these ideals, we make LiveRoof available for pairing with all appropriate waterproofing products (from all manufacturers). We can suggest typical waterproofing build-ups, and in every case the manufacture’s “approved LiveRoof-compatible build up” should be specified and followed.
Retention means that a specific volume of water is retained on the roof for an indefinite period of time. Detention means to temporarily detain stormwater before discharging it as runoff.
RoofBlue DETAIN is intended for use as part of a water detention system, whose main function is to delay and control the flow of stormwater runoff. This delay allows more time for municipalities to treat runoff, which helps to prevent stormwater and combined sewage systems from overflowing (untreated) into local waterways.
RoofBlue RETAIN is LiveRoof’s patented solution for stormwater retention. It captures and retains stormwater, following a storm event, transferring water upward towards the plant roots as the soil dries out, to keep soil appropriately moist and plants healthy. This can result in enhanced plant growth, lower irrigation needs, and increased stormwater management on your green roof.
- RoofBlue DETAIN raises the modules an additional 3.5” from the roof surface. The void space inside the RoofBlue DETAIN module is approximately 90.5%.
- At 3.5”maximum water depth, RoofBlue DETAIN provides up to 455 cubic inches (approximately 2 gallons or 7.4 litres) of water detention per square foot.
- The control flow roof drain insert should be even to the lowest point of the green roof installation, the water will not exceed 3.5” in height. This ensures that the plant roots are kept out of standing water.
Control flow drains are designed to slow the rate of runoff from roofs during storm events. These drains typically have an insert with a weir that regulates the flow of water through the drain. They are available in a variety of heights. Generally, flat roofs have lower weir heights than sloped roofs. Some models have adjustable weirs which can be set for each drain / location, and some may utilize copper flanges to inhibit root growth. All control flow drain systems should be carefully designed by a licensed professional engineer. These manufacturers sell controlled flow drains:
RoofBlue DETAIN applications should be designed to hold no more than 3.5” of water beneath the green roof system.
Each inch of water weighs approximately 5.2 pounds per square foot, so at maximum water detention, the blue roof solution would add up to 18.2 pounds per square foot of load to the weight of the green roof modules (find saturated weights here).
The maximum saturated weight of the RoofBlue RETAIN system depends on the LiveRoof modules used:
- <= 29.5 lbs/ft2 for Lite modules
- <= 41.5 lbs/ft2 for Standard modules
- <= 62.5 lbs/ft2 for Deep modules, and
- <= 77.5 lbs/ft2 for Maxx modules
In our experience, most roofing assemblies recommend that water does not stand for longer than 24 hours.
However, we recommend that architects and engineers confirm the maximum amount of time allowable for detention with the membrane manufacturer before specifying the type, size and placement of drains and pipes.
RoofBlue is compatible with all LiveRoof module sizes. RoofBlue DETAIN will raise the green roof system by an additional 3.5”, which means that taller aluminum edge restraints are required to surround the entire blue green roof assembly.
Edging Recommendations
Most membrane manufacturers will have special requirements for blue roof applications. In the early stages of blue roof design, is absolutely critical for engineers and specifiers to work with membrane manufacturers to select appropriate materials, thicknesses and to provide assembly instructions according to local code.
Also, confirm that the waterproofing specification complies with code. Some municipalities have specific requirements for blue roof applications. (Example: New York City stormwater construction guidelines address blue roofs).