Under Construction: Fort Wayne’s First Green Roof

Dan Skinner is standing underneath crisscrossed steel beams describing a waterfall – not one on some far-off tropical island or mountainside retreat but one about 30 feet from where he’s standing.

In other words, right next to a whirring circular saw that whines incessantly until a looming thundershower makes using power tools on a third-story office rooftop a bad idea.

But even in the midst of piles of concrete paving block, orange extension cords and stray pieces of pink foam insulation, the 46-year-old Skinner can see a horticultural oasis that by next spring will become perhaps the most unusual garden in Fort Wayne.

The garden will be on the roof of the new headquarters of Petroleum Traders Corp., a space described by its designers, including Skinner, owner of Emerald Landscape in Fort Wayne, as the first “green roof” on an office building in the city.

Proponents of green roofs say well-designed ones have a number of benefits – from providing pleasing aesthetics to controlling rainwater runoff and reducing a building’s energy consumption. Plants on green roofs consume carbon dioxide and provide oxygen to smog-choked urban areas, and the roofs also may combat global warming by alleviating the urban heat-island effect – the higher temperatures that occur in cities when large numbers of large buildings packed in a small area absorb the heat of the sun.

In Europe and other U.S. cities, green roofs are becoming a design and construction trend as a way of improving urban environments, says Vanessa Bender of Habitat Commercial and Residential Design and coordinator of the project. In Chicago, for example, Mayor Richard Daley has spearheaded an initiative to landscape rooftops city wide, and incentives already have reaped more than a million square feet of rooftop under cultivation.

“There’s a lot of interest in this,” she says of the concept. “It is a big deal.”

A need for green space amidst a sea of asphalt and concrete isn’t the reason for building this green roof, inasmuch as it’s in the middle of a suburban-style office campus with plenty of grass and trees surrounding it. But the roof’s mastermind, Michael Himes, chief executive officer of Petroleum Traders, says creating a natural environment for employees to enjoy is.

The rooftop garden will open off an employees’ break room as well as his own glass-walled office and will include chairs and tables for lunching and meetings.

“With all the built landscapes that are surrounding our lives, there’s less greenscapes in our lives, and it’s an attempt to balance that,” he says.

“I think I like the concept of a green roof in terms of its health quotient and as a positive factor of the building in terms of its function.”

Skinner says in designing the space he strived to provide serenity in the otherwise fast-paced, occasionally stressful and certainly technology-intensive environment of a company that buys and sells petroleum.

“Landscaping influences the attitudes of the people in that environment,” says Skinner, who imagines the garden as a place where the all the senses will be engaged, but soothed – by the sound of running water, with the colors of the changing seasons and with the graceful movement of ornamental grasses and tall and dwarf bamboo plants.

“I think he’s making a tremendous investment in the state of mind of everybody who works here,” Skinner says of Himes, a plant collector who has a $10,000 bonsai tree in his office and considered putting a green roof on his home and expects more to follow on commercial buildings in the region.

“They won’t have to be a pioneer,” Himes says of the next green roof builders. “They can see it makes sense and works.”

This is the first green roof Skinner has designed, he says, although the 46-year-old graduate of Michigan State University’s well-known horticultural program worked on some early green roof projects in Chicago for another employer. For him, the project has been an exercise in “extremes gardening” – and not just because of the 10,000 pounds of rock that his water feature requires, or because he’s got to rent a crane to lift the trees he’s planning into place.

“The conditions are really extreme up here,” he says of the L-shaped space that covers 1,947 square feet about two-thirds of which is covered with garden. “It’s always hotter and always colder and windier up here than down there.” The difference can be as much as 10 to 20 degrees.

It’s also drier for the plants because of the limited soil depth and constant exposure to largely unfiltered sunlight which hastens evaporation. The garden required laying an extensive irrigation system, as well as an elaborate mat drainage system on the roof to funnel excess water away. The water will go into the buildings drainage system to the storm sewer.

Even so, Skinner is looking to hardy and drought-resistant plants, including four kinds of sedums to surround his waterfall and grasses, and an engineered soil mix to make his plan work. In other words, the plants won’t be growing in any old dirt but dirt that is closer to potting soil.

The design also had to take into consideration weight – soil will get heavier as it absorbs water, snow will fall and lay, trees will grow and retaining walls and pavers and furniture and people will all provide poundage that the roof must handle.

All these weighty aspects had to be cleared through the building’s architect, Design Collaborative of Fort Wayne, and structural engineers, before installation, Skinner says.

The project’s roofing contractor, C.L. Schust Co., Inc., of Fort Wayne, and general contractor, W.A. Sheets & Sons, had to be on board, he says. “It takes a lot of people, and a lot of cooperation, to do something of this size,” he notes.

Indeed, one part of the garden was redesigned to take more advantage of structural supports of the building and another was redone to include more insulation so soil weights wouldn’t be as heavy, Skinner says.

Besides the waterfall utilizing the rocks and a reflecting pool with koi fish, water lilies and iris, the garden will include shrubs, evergreens and leaf-bearing trees. There will be raised beds containing ornamental grasses and stretches of lawn, originally laid as sod by also seeded for the long-term. Perennial and annual flower accents will include ground-cover roses, orange poppies, salvia and several large container gardens provided by Ken Hensch of Aesthetic Plant Specialists, Fort Wayne. The containers will likely change seasonally, he says.

Hensch says he also may eventually be recruited to provide plants to cover the steel beams for a pergola-like effect.

Trees include a Boyd’s weeping willow for the waterfall area, Japanese maple, dogwood to provide fall color and a food source for birds and a weeping crabapple, Skinner says. Butterfly bushes should attract those creatures, he notes. And no season has been neglected. “There should be something in bloom as late as Halloween,” Skinner says.

A corner with a raised platform may be used for performances by musical groups or as a stage during meetings. “I expect him (Himes) to entertain out here a great deal,” says Bender, who has planned lighting for the area and come up with burnished aluminum and teak furniture that seats 16 for the space.

By the end of the first year, Skinner says, the beds will probably no longer need mulch as natural processes take over.

But he stresses the plants will have to be constantly monitored. With a rooftop garden, he says, “you have to plan on the side of failure. You have to envision and plan on the worst-case scenario,” says Skinner, who nonetheless says he’s found the project enjoyable, despite several delays because of weather and change orders.

“Mostly because this is a very far-sighted and educated client,” he says of Himes.

“Visionary,” adds Bender.