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Jay R. Smith Mfg. Co.® Green Roof and Cool Roof Drains
We have the right green roof drain for any drainage application.
 

Green Roof and Cool Roof Drains

A green roof is a vegetated roof with growth media composition to support growing plants. It provides evaporative cooling, converts carbon dioxide to oxygen and reduces stormwater runoff. Green roofs can also include cool roofs (reflective roofs). Overall, green roofs offer a wide range of social, economic, and environmental benefits compared to typical commercial roof tops.

The drainage off a green roof surface is a particularly important component to maintain optimum growing conditions in the growth medium, to managing heavy rainfall without sustaining damage to growth media due to erosion or ponding of water, and to ensure the sound engineering and structural integrity of the roof.

Our line of engineered roof drains includes professional grade Area, Scupper, Overflow, Planter, Plaza, Siphonic, and Traditional roof drains for all types of conditions and aesthetics. Our cast iron and stainless steel roof drains can be furnished with a stainless steel gravel stop and dome; a bronze flashing clamp, dome, and standpipe; a fabricated stainless steel drain; or cold dipped galvanized cast iron body.

As an industry leading manufacturer of plumbing and drainage products, we have developed a line of green roof and cool roof drains that are engineered to work on extensive, intensive, multifunctional, and cool roofs.

Typical Features and Benefits of Green Roofs and Cool Roofs
Stormwater Management – A green roof design works by retaining water, in some cases as much a 75% to 90%, thereby significantly reducing stormwater runoff. The reduced runoff lessens the pressure on drainage facilities and flooding. This applies to vegetated roofs only.
Adds Protection for the Waterproofing Layer – The build up above the waterproofing membrane is proven to greatly increase life expectancy by reducing the impact of temperature fluctuations, thereby reducing thermal stress. Green roofs help moderate the roof’s temperature swings throughout the year. These temperature extremes in summer and winter can cause the roof to expand and contract, which eventually causes the roof membrane to crack and need repair and replacement. Additionally, ultraviolet light degrades roof membranes not protected by green roofs. This applies to vegetated roofs only.
Reduced Energy Consumption and Maintenance – The roof top plants and/or cool roof materials increase the installation in the building and reduce heat transfer into the building thus lowing utility rates. Green roofs can reduce energy consumption of a building by up to 20%. This applies to green and cool roofs.
Reduces Urban Heat Island Effect – This is where there is an increase in ambient temperature in cities because paved areas and buildings absorb more heat from the sun than natural landscape. Green roofs help insulate and shade buildings, and the plants can help cool the atmosphere around them. This applies to green and cool roofs.
Other Advantages of Green Roofs–
  • Creates a living habitat for wildlife;
  • Creates more accessible space in densely populated areas;
  • Are more aesthetically pleasing than a traditional roof;
  • Reduces noise transmission by upgrading acoustic performance;
  • Improves ambient air quality; and
  • Contributes to sustainability and enhances local biodiversity.
   

Roof Designs

LEED Credits

The installation of a green roof can help a facility earn as many as
13 credits toward LEED certification.

  • Reduced Site Disturbance - Potential Rating: 1 point.
    This applies to a green roof.
  • Storm-Water Management - Potential Rating: 1 to 2 points.
    This applies to a green roof.
  • Heat Island Effect - Potential Rating: 1 point.
    This applies to green and cool roofs.
  • Water-Efficient Landscaping - Potential Rating: 1 to 2 points.
    This applies to a green roof.
  • Optimize Energy Performance - Potential Rating: 1 to 8 points. This applies to green and cool roofs.
 

What are extensive, intensive,
multifunctional, and cool roofs?

An extensive roof planting features plants that require low maintenance such as decorative grasses and herbs. A low build-up in the form of a planting substrate is sufficient for them. A well-designed system contributes to improving the roof’s acoustic and thermal performance.

An intensive roof planting features a lawn and/or plants requiring regular maintenance such as bushes, trees and shrubs along with ground cover plants. These systems have a far greater depth of soil and require good drainage to ensure that the roof does not become water logged.

A multifunctional roof features intensive roof planting combined with roof paving. Various combinations of planting applications are possible: intensive roof plantings combined with footpaths, play facilities, or with vehicular traffic. Loading and drainage are considerably more significant with this roof design.

A cool roof features a roofing system that can deliver high reflect solar reflectance (the ability to reflect the visible, infrared, and ultraviolet wavelengths of the sun, reducing heat transfer to the building) and high thermal emittance (the ability to radiate absorbed or non-reflected solar energy). Most cool roofs are white but they can be other colors. They are also called reflective roofs. Cool roofs enhance roof durability and reduce both building cooling loads and the urban heat island effect.  

A green roof and/or cool roof offer positive thermal benefits in the respect of controlling the temperature variations on the roof surface and underlying structure, in particular, they reduce loads on building air conditioning and heating systems. Protecting the roof membrane from sun and weather exposure with a natural green surface or coating/tiles/shingles can extend the lifespan of the roofing material, thus reducing long term maintenance costs.