Raising the Roof

ST. LOUIS -- Kelly Luckett has always seen green in roofs — green as in money. His north St. Louis County company, St. Louis Metalworks Co., has captured a strong niche business, fabricating sheet metal used in roofing.

These days, however, Luckett is seeing more green. He has joined a leading edge of companies nationwide turning rooftops into botanist landscapes. Green Roof Blocks, a subsidiary of St. Louis Metalworks, installs greenery for nonresidential roofs.

If his dream comes true, commercial roofs throughout the region will become lush with plants rooted in Luckett's specially designed square pans that fit together like a jigsaw puzzle. But first, he has a lot of convincing to do.

Customers need to know what's in it for them to spend about $10 per square foot to grow plants on their roofs.

Luckett can start with a history lesson.

"Covering roofs with moss is an ancient method," said Philip Lum, principal at Manske Corporation Architects in Riverview. He has worked with Luckett on a Green Roof Blocks project.

Today, roofs throughout Europe are dotted with plants.

Besides being eye-catching, green roofs have several practical elements. The plants hold water during storms, minimizing runoff. They limit heat build-up in the summer and keep roofs insulated in the winter, lowering utility bills.

And plants typically make the underlying roof last longer by cutting down on moisture and offering protection from wind, hail and ice.

Though green roofs have not caught on in the St. Louis area, Luckett says it's only a matter of time. Green roofs have become an integral part of a growing environmental movement in design called LEED, or Leadership in Energy and Environmental Design.

"I started thinking about it after I read an article about green roofs in a trade magazine about a year and a half ago," Luckett said.

Luckett thought he could improve on the traditional green-roof design, which generally consists of creating a single growing environment atop a roof. The design, he figured, did not allow for easy maintenance.

If a roof leaks, it's difficult to find the source — much less make repairs — with plants growing as a single mass. In addition, all roofs eventually fail and must be replaced. Under the traditional design, the plants and the roof membrane are tossed out together.

"Even though it makes the roof last longer, at some time, this is going to have to come back off," Luckett said. "I thought, have a container that you can move away."

With the blocks, leaks can be discovered and repaired simply by lifting individual blocks out of the way. Sections can be moved temporarily to replace or repair parts of a roof.

Green-roof blocks sit just above the roof on rubber pads. They have holes near the bottom of the blocks to allow water to pour through.

"It's a lot more practical product," Lum said.

The block system is installed by roofers, rather than the landscapers who put in traditional green roofs. That's a trait desired by Luckett, a roofer by trade.

"A landscape contractor putting materials on top of a roofer's brand-new roof — roofers absolutely hate that," he said. "We don't want anybody on our roof but us."

Weight generally isn't an issue. Most commercial roofs need about 10 pounds per square feet of ballast — often stones — to hold them down. The green blocks, which weigh 15 pounds per square foot, replace the need for ballast.

The plants are not placed in soil, but instead sit in a largely inorganic engineered soil that looks like pebbles. One group of plants, called sedum, particularly likes the growth medium.

Vic Jost of Jost Greenhouses in Des Peres is consulting with Luckett and providing sedum.

"They are succulents, and they are hardy," he said. "They can survive on little water."

Indeed, sedum roots generally need to be dry, or they can rot and die.

Sedum comes in seemingly endless varieties, with different colors and characteristics that allow it to thrive in most environments.

Green Roof Blocks is just starting, so it's a relatively minor customer for Jost Greenhouses. But the owner sees a strong potential upside.

"I think it's got a lot of environmental impact," Jost said. "I think in the future it could be a good portion of our business."

Tom Tyler, president of Answers Inc., an architectural firm in west St. Louis County, is another believer in the block system.

Unlike traditional green roofs, the block system easily can be placed atop virtually any existing roof.

"You go to someplace like Chicago, they will go through a huge amount of construction to put a green roof on a new building," Tyler said. "This block project, you can achieve that over an existing roof membrane."

Though his building exceeds aggressive energy-savings standards, Tyler has a few of the blocks on his roof.

"So, what's the benefit?" he said. "The benefit is you get to set an example."

Luckett knows that ultimately, sales will depend on proving that the extra cost of a green roof will be repaid in multiples through energy savings and a longer-lasting roof.

With few building owners willing to pay $10 a square foot to be a test subject, Luckett is taking his time, rolling out demonstrations of the block system. A roof at the Missouri Botanical Garden pavilion, which Lum helped to design, has the blocks. Luckett also has donated blocks for a project at the University of Georgia, which has been a leader in researching green roofs.

"We want some credible source to conduct research to show that our simple system has all the benefits of a more complicated system," Luckett said.