Green Roofs Open Markets

The "green roof" is making a comeback. While it's a trend many Americans just now are being introduced to, it's been around for centuries in many parts of the world. Simply put, a green roof is one where some sort of vegetation is grown on top of the building.

"It's something so old, it's new again," says Ralph P. Velasquez, president of Nashville, Tenn.-based Integrated Building Technologies LLC. "We had the Babylonian Hanging Gardens thousands of years ago, and the sod roof on homes in Europe."

Widely used today in Germany and Scandinavia, green roofs usually fall into one of two categories: intensive and extensive. Intensive green roofs may have soil depths of up to 4 feet. Extensive green roofs usually have soil depths of no more than 6 inches. The soil is a pre-engineered media with very little actual dirt in the mixture; it then is planted with hearty, drought-resistant plants and can include areas for picnics or relaxing.

Is the Green Roof Market for You?
As a landscaper, you might look at the green roof phenomenon as one you'd like to be involved in. But there are several things to consider before you take the plunge.

Ed Snodgrass, owner of Street, Md.-based Emory Knoll Farms Inc., and a green roof horticultural consultant, says many considerations aren't obvious at first glance.

"First, you need to look at this administratively," Snodgrass says. "You need to ask, Does my workmen's compensation insurance cover me to be on a roof? Do we need a safety officer or harnesses on site? You don't want all of your profits swallowed up by an OSHA fine."

Understanding your place in the building's mechanical system is also a must, Snodgrass says. "You're part of a building system now. You need to understand flashing, materials and handling," he says. "Where do you fit into the building scheme? You don't want to put down your media and plants and then have the air conditioning people come in and tromp all over it."

Working in green roofs means developing relationships with architects, general contractors, roofers and other professionals. "You want to be on the roof after all the other subcontractors are gone. The burden and the effort to get people and materials on a roof are different than when you're on the ground," Snodgrass says.

This becomes evident when the roof suddenly springs a leak, says Chuck Scislo, senior technical director for the Rosemont, Ill.-based National Roofing Contractors Association.

"We treat green roofs as a waterproofing specification," he says. "If a leak occurs with a green roof, it could be very expensive to repair, because you're digging through several inches of media to find it and get to it."

Costs for installing a green roof are all over the board, Snodgrass says. "I've seen them installed for as little as $12 per square foot," he says. "On the other hand, we had one client who put a $60,000 kitchen with fiber-optic grouting out there."

Snodgrass suggests that landscapers look at their overall business model before deciding to move in the direction of green roofs. "Everyone says at first, ‘Yahoo! More money, more work, more prestige!'" he says. "But it takes some serious investigation before deciding to go this route."