If a leak in a waterproof membrane—untraceable to the naked eye—meets a season of wet weather, it can mean a perfect storm for costly water damage.
“You especially don’t want a breach in your green roof,” says Chris Eichhorn, the president of International Leak Detection (ILD), which has built a reputation for testing green roofs, including the parking garage topping Maggie Daley Park in Chicago. “We believe in the environmental value of green roofs, and so we’ve worked hard to make the testing accurate, even through inches of overburden. With EFVM (Electric Field Vector Mapping), we can read through the soil, pavers, and ballast without the need for a project to be dismantled, so we can test existing green roofs and plazas, too.”
A former roofer himself, Eichhorn has devoted the past 14 years to perfecting the EFVM method to test roofing and waterproofing membranes. Since 2001, ILD has tested more than 250 million square feet of membrane all over the world—including on some of the world’s most iconic buildings, such as the Empire State Building, the 9/11 Memorial Plaza, and the Library of Congress—and boasts a startling 100-percent accuracy rate. “We don’t leave the roof until it’s 100-percent breach-free,” Eichhorn says.
“We believe in the environmental value of green roofs,” says Chris Eichhorn, the president of ILD, “and so we’ve worked hard to make the testing accurate, even through inches of overburden. … We can read through the soil, pavers, and ballast without the need for a project to be dismantled, so we can test existing green roofs and plazas, too.”
EFVM—which has largely replaced flood testing, in terms of speed, ease, and accuracy—works by applying water to the membrane surface and delivering a low-voltage pulsating charge between the nonconductive membrane and the conductive structural deck. Any breach will cause an electrical connection to occur. Breaches are circled, numbered, and documented in a report by ILD inspectors, and repairs are made by the contactor.
In addition to Maggie Daley Park, ILD recently tested the 309,300-square-foot green roof of the Javits Center in New York City and Levi’s Stadium, the new home of the San Francisco 49ers and the first LEED Gold football stadium in the country.
Maggie Daley Park, designed by Michael Van Valkenburgh Associates, is actually built on top of a downtown parking garage. ILD, which can detect breaches with 100% accuracy, was hired to ensure the parking structure’s roof was watertight.
Bill Schaefer, the north-central district manager at American Hydrotech, which manufactures the waterproofing products used at Maggie Daley Park, relies on EFVM regularly and says ILD is “one of the best testing agencies out there.”
Eichhorn estimates that ILD has saved its clients almost $20 million since it adapted EFVM to North American standards, in part because the company can test up to 20,000 square feet in a single day. “Not only are we sticklers for quality,” he says, “but we work fast to promote an on-time schedule.”
