Ten years after Ford planted vegetation atop a truck-assembly plant, the largest living roof in the U.S. is flourishing and others have followed the automaker’s lead.
Ford was a pioneer a decade ago when it created a living roof on top of the Dearborn (Mich.) Truck Plant. It was a unique way to save on roofing materials and cooling costs while addressing water runoff and other ecological concerns.
“Ford was incredibly courageous and forward thinking when they evaluated and moved forward with a green roof,” said Clayton Rush, manager of Xero Flor America in Durham, N.C., whose parent company in Germany worked with Ford on the project. “They became a well-recognized pioneer.”
The success of the Dearborn truck-plant roof prompted Ford to do more. A year ago, when a 2,500-square-foot portion of Ford headquarters needed to be redone, the automaker turned a second time to water-absorbing plants.
When Ford took the plunge, there were fewer than 50 living roofs across the United States. Today, there are about 10,000 and the number is rising, Rush said, with numerous companies supplying them. They adorn everything from doghouses and homes to commercial, government and academic buildings.
Grasses now grow on the Empire State Building; Nintendo headquarters in Redmond, Wash.; a FedEx facility at Chicago O’Hare International Airport; and a 7-acre spread atop the Javits Convention Center in New York.
Don Russell worked in Ford’s environmental-quality office in 2000 when he was given a unique assignment: Refine Bill Ford’s vision to reinvigorate the historic Rouge industrial complex by covering the roof with grasses instead of tar or shingles.
“I’m a chemical engineer, so it was far from my comfort zone,” Russell remembers. “I was told to evaluate what was out there commercially to do this roof.”
The assignment was more than ecological whimsy. Ford wanted to expand the facility, situated in marshland. There was a cost of about $50 million to meet new water-quality regulations by reducing toxic stormwater runoff from the plant site into the Rouge River.
Famed eco-architect William McDonough was tapped by Bill Ford to develop the master plan for plant expansion and installing a 10.4-acre roof of thirsty grasses and meadows over porous paving materials as a natural stormwater management system at a cost of only $15 million. Ford spokesman Todd Nissen said studies show the roof has reduced runoff by 42 percent and what does leave the roof contains 85 percent fewer suspended solids.
Russell’s research found that while roof gardens weren’t being done in the United States, Europeans had been doing them for 40 years. The truck plant roof could support 25 pounds per square foot, and Xero Flor of Germany had a lightweight vegetation that weighed only 11 pounds per square foot when saturated with water.
About 15 acres was turned into a farm to grow a collection of 11 plants known as sedum, and in fall 2002 the sedum was installed on the roof, much like laying sod.
Rush said the Ford roof cost $8 to $15 a square foot to install and maintenance is 5 cents to 50 cents a square foot annually.
After Ford’s large-scale project, the idea gained popularity, Russell said. “The rest of my career was giving presentations and responding to mail about it,” he said. Although he retired in 2006, the 64-year-old was asked earlier this year by the company that maintains Ford grounds to help look after the roof again. Russell checks it once a month.
Business, Pages 69 on 10/27/2013