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Landscapers See Opportunity in the Sky
1 Jan, 2008 By: Brian Albright LivescapesGREEN ROOFS PRESENT OPPORTUNITY, CHALLENGE TO LANDSCAPE COMPANIES
Landscape designers spend a lot of time looking down—understandable, since their livelihoods are linked to the soil. But Kurt Horvath, owner of Intrinsic Landscaping in Glenview, IL, has his head in the clouds these days. Horvath is one of a growing number of landscapers specializing in the design and construction of green roofs, those eco-friendly islands of greenery that dot formerly drab roofscapes around the world.
 INTRINSIC LANDSCAPING has installed green roofs on schools its corporate headquarters and the city's recycling center. Chicago is a pioneer in green roofs, largely because of the city government's support for green roofs. |
According to Green Roofs for Healthy Cities (GRHC), the North American industry association, green roof installations in 2006 were up more than 25%, representing more than 3 million sq. ft. For intensive green roofs, which incorporate larger plants, the growth rate was 110% during the same period.
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Horvath's company, which includes a nursery and two landscaping divisions, was contracted to install its first green roof in 2000. More than 100 installations later, he has built a new business focused on rooftop projects, as well as a subsidiary that manufactures and distributes green roof components.
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"Those installations have been a mix of anything and everything," Horvath says. "If you can put it on a roof, we're there."
There is expected to be significant opportunity in the green roof market as more and more businesses and homeowners look for ways to reduce their impact on the environment, but do your homework before leaping into a project. Unlike traditional installations, or even simple rooftop gardens, green roofs require a wide variety of expertise, ranging from horticulture to structural engineering.
"There's more to green roofs that meets the eye," says Steven Peck, founder and president of Green Roofs for Healthy Cities. "There are a lot of ways to mess up a green roof. It's a living system. It's very important to follow the lessons we've already learned to make sure it doesn't leak, that the plants survive, and that you get the maximum benefit for your climate."
Green Roof Benefits
Green roofs can range from smaller plantings on residential homes to the massive, 10.4-acre "living roof" at Ford Motor Company's historic River Rouge Plant in Dearborn, MI. Building owners install the roofs for a variety of reasons, ranging from concerns about the environment to simply providing usable green space for their employees or tenants.
 A VIEW of ASLA's green roof from a nearby building . |
There are also hard-dollar benefits. It's estimated that green roofs can last up to twice as long as conventional roofs by protecting the roof membrane. Depending on the size of the building and the climate, these roofs can also help keep buildings cooler in the summer, and even insulate against noise.
 SILENE CAROLINIANA give the "south wave" of ALSA's green roof a burst of color at the beginning of spring. |
One of the most significant benefits, though, is the reduction in stormwater runoff. Depending on the plants and depth of the growing medium, these roofs can retain 70 to 90% of precipitation in the summer. Green roofs can potentially reduce flooding and sewer overflow, as well as act as a natural filtration system.
In 2006, the American Society of Landscape Architects installed a green roof on its downtown Washington, D.C., headquarters, and closely monitored its effects on temperature and stormwater runoff. According to a report issued in September 2007, the roof retained nearly 75% of all precipitation, and lowered the roof air temperature by as much as 32° in the summer, compared to a neighboring tarred roof. Engineering analysis showed that the roof's extra insulation lowered energy usage in the winter by 10%.
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