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FiberTite® roofing with Elvaloy® KEE resists jet fumes, environmental abuses

The airport environment takes a heavy toll on neighboring buildings. There are few shade trees or hills to give protection from sun, wind and heavy rain. Pollution from automobiles, airport trucks and service vehicles further deteriorate structures. Roofs are especially vulnerable to damaging exhaust from low flying aircraft.

The roof of the Navy/Marine Corps Reserve Center next to Orlando's Executive Airport experienced gradual deterioration from strong ultraviolet radiation, hot temperatures, jet engine exhaust and bacteria in the humid Florida air.

A recently installed FiberTite® roofing membrane containing DuPont™ Elvaloy® KEE ketone ethylene ester is expected to provide a long-lasting, watertight covering for the building. Its single-ply, lightweight design permitted a simple reroofing over the existing cover, saving weeks of costly labor and inconvenience to the Center's staff.

Break from Tradition

The Center had numerous leaks in its original built-up roof. According to Kurt Musser, construction manager at the facility, the U. S. government traditionally specified built-up roofs of this type, and regularly patched the BUR when leaks occurred.

Stanley Peters, consulting architect for the Navy, specified single-ply roofing membranes for the Orlando facility. Ease of installation and membrane integrity were key reasons. Contemporary Roofing Inc., Jacksonville, Fla., was the successful bidder with a FiberTite roof.

The FiberTite roof's documented resistance to deterioration from jet fuel and its watertight properties met the specifications for the project.

FiberTite, an ethylene interpolymer alloy produced by the Seaman Corporation, provides excellent resistance to deterioration caused by airborne fumes, bacteria and ultraviolet exposure, Chemical resistance comes from the inclusion of Elvaloy® KEE, a permanent plasticizer that does not migrate, allowing the ethylene interpolymer to maintain its properties indefinitely. The membrane is reinforced with tough DuPont Dacron® brand polyester fiber.

Fuel Resistance Documented

Resistance to deterioration from jet fuel was recently documented at DuPont's Technical Service Laboratory, Wilmington, Del. Strips of the ethylene interpolymer membrane containing Elvaloy® were immersed in jet fuel for two years. The result was a membrane that remained stable and showed no significant change in key properties such as tensile strength, elongation, weight change and Graves tear resistance.

Benjamin Smith, Seaman Corporation's sales engineer, says such tests show the membrane is extremely durable. "No roof will ever be immersed in jet fuel like the sample in this test. However, if treated ethylene interpolymer materials withstand extreme aggravation in the laboratory, they'll withstand decades of environmental punishment on a roof."

A recently installed Fibertite roofing membrane containing DuPont Elvaloy® resin modifier is expected to provide a long-lasting, watertight covering for the Navy/Marine Corps Reserve Center, located next to Orlando, Executive Airport.

Ease of Installation

In addition to Fibertite's outstanding chemical resistance, its lightweight single-ply design permits installation over existing roofs without adding significant weight. This means building owners can avoid expensive labor and material costs associated with the complete replacement of an existing roof.

Ease of installation was especially important at the Navy/Marine Reserve Center because of the complexity of the job. The building consists of three separate sections: a main structure and two additions, each with different roof installations.

"These roofs are a bewildering array of slopes, ridges and buckles," Peters said. "Each has different types of flashing and different methods of handling penetrations and edges."

Since the original insulation was intact, Peters preferred re-roofing the entire building with a lightweight membrane instead of ripping out the old cover and rebuilding it.

Another factor was Orlando's weather. "The area gets a daily thunderstorm during most of the year," Peters said. "Since the Center usually operated 24 hours all year long, there is no way to safely remove the old roof without subjecting people and equipment inside to a possible soaking or the noise and pollution from the airport."

The Reserve Center re-roofing took 15 days to complete compared with many months needed to install a new, built-up roof. There have been no leaks since installation of the ethylene interpolymer on the Center.

Roofing Manufacturer Link

Seaman Corp., FiberTite® » Visit FiberTite Web site