Incentives Boost Ecoroof Popularity in Oregon

On the circa 1965 split-level home of Anne and Fran Hanchek, an 18-by-18-square-foot roof grows thyme, sedum and crocuses — something you might expect to see in hip Portland, Ore., neighborhoods or on newer buildings downtown — but not in an area of Washington County outside the city limits. If ecoroofs are sprouting up in the suburbs, does that mean they've gone mainstream?

Not quite. But it could mean that vegetated or green roofs, as they're also known, are near a tipping point.

"The idea is gaining recognition," says Tom Liptan, a landscape architect for the city of Portland's Bureau of Environmental Services and a nationally known ecoroof expert. He is credited with incubating the movement in Portland, planting the city's first ecoroof on his garage in 1996.

The number has grown steadily since, here and abroad.

In some Asian and European countries, where the practice began centuries ago as sod roofs, officials are rewriting city codes to demand that new construction come equipped with green roofs. In Portland, 80 green roofs two years ago grew to the current 120.

City leaders recently upped the ante by penning a goal: to grow 43 acres of new green roofs in the next five years. There are currently 12,500 acres of conventional roofs citywide.

Why the big push?

The environmental benefits are undeniable, and the nudge could launch an industry and might even create jobs.

Ecoroofs reduce "urban island" heat, improve air quality by reducing temperatures and smog, and increase a building's insulation, which reduces energy consumption. Green roofs also create wildlife habitat and reduce stormwater runoff that can pollute streams.

To make ecoroofs attractive, Portland officials for seven years have offered developers a density "bonus," allowing more floors in a new high-rise, for example, in exchange for a green roof.

City leaders raised the flag higher when they passed a 2005 resolution to convert any roof in need of replacing on city property into a green roof unless structural or other problems make it a bad idea economically.

For homeowners, the city reduces the stormwater runoff fee. Last July, the city launched then-Commissioner Sam Adams' "Grey to Green Initiative" program, which dispenses grants to subsidize, among other things, up to $5 per square foot on new ecoroofs.

The cost of a green roof, though declining, still turns off some people.

The Hancheks converted the roof of their family room — an addition to the original house — for $2,300 spent on plants and supplies — or roughly $8 a square foot, not including labor. They saved on labor by participating in a volunteer program in which Washington County master gardeners help with installation.

An ecoroof should ideally cost between $6 and $8 a square foot, Liptan says, but he's seen plenty that averaged $15 to $20. The problem is that ecoroofs, as an industry on the West Coast, are still in their infancy, and no local businesses have streamlined the production of materials and designs. One of the goals of the push to grow 43 acres is to fuel an industry.

Greg Haines, owner of Ecoroofs Everywhere, saw enough demand that he turned his 6-year-old nonprofit into a business last year. Now, he's trying to earn an income installing green roofs in Portland and Vancouver. Haines, who has taught an "Introduction to Residential Greenroofing" class at Portland Community College, says interest is growing.

"When I started, I thought it would be kids pressuring their parents, like recycling, but it didn't work like that at all," Haines says. "I think people can see it. And once their fears of water leakage and insects — things people used to ask about but don't anymore — are addressed, they get it."

Not everyone is there yet, though.

Some people still think it's weird to grow things on a roof. Others fear the added weight. Planners advise anyone considering an ecoroof to have the structure checked by an engineer to determine what weight it can bear. Ecoroofs add roughly 10 to 25 extra pounds per square foot when saturated, depending on the vegetation and planting medium.

Other people don't think their roofs have enough pitch, though ecoroofs can be located on flat or pitched roofs at a slope of up to 40 percent. Still others worry about watering and weeding.

The Hancheks, who installed their ecoroof in October, expect to climb up a couple of times a year to pull up seedlings started by seeds dropped by birds and squirrels or carried by the wind. They hope, however, they set out strong plants that will carpet the roof and choke out weeds.

Some of the city's earliest ecoroofs withered into weed lots and created ongoing discussion about what plants work best, what an ecoroof should look like in Portland's dry summers, whether native plants fare better than imports, and whether watering a roof in summer negates the other environmental benefits.

Liptan believes education is a key to further expanding the movement. To deal with perceptions, the city is hiring an outreach coordinator. Liptan's office is considering a vendors fair in late spring or early summer. The city also continues to stockpile information, from a growing local resources list to a plant guide to a cost analysis of the benefits. The info is online at www.portlandonline.com/bes/ecoroof.

The trove of knowledge is important because most of the research available comes from Europe and the East Coast, and not all of it is applicable to Portland's climate.

Sean Hogan, a horticulturist who owns Cistus Nursery on Sauvie Island and has worked on some of the most public ecoroofs in Portland, welcomes more studies, particularly about the use of Willamette Valley native plants.

The Hancheks didn't choose natives but picked plants that succeeded on other area ecoroofs, particularly plants that tolerate poor soil and drought. "I imagine we'll fine-tune the plants," says Anne Hanchek. "You have to choose things you know are going to work well. It's basically a great big dish garden you are growing outdoors."

Since the movement took off in Portland in the late 1990s, enthusiasts have learned lessons about soil type, depth and plants. Scientists at Oregon State University are studying the systems more, and city environmentalists have their eyes on a few green roofs owned by businesses and homeowners willing to experiment. They're testing everything from conifers to the viability of plants sown from native seeds.

Back in unincorporated Washington County, the Hancheks view their new roof as an experiment. Because it can't easily be seen from the street, they haven't heard much from neighbors regarding the aesthetic. But they live in a community, Anne Hanchek explains, where homeowners enjoy individualizing their space, so they don't anticipate anything other than support and curiosity, of course.