October 12, 2000

Green shingles may be no match for gray weather

New roofing products come and go, but San Antonio-based US Century's recycled rubber tire shingles come with a unique endorsement, according to CFO Terry Colip: presidential candidate George W. Bush may use it on his ranch house.

The product itself could be a candidate for one of the most environmentally friendly roofing shingles on the market.

FlexShake, as it's called, which has been on the market for about a year, is 90 percent recycled waste tires, manufactured in partnership with Goodyear Tire and Rubber Company. The shingle is produced from the tread of the tire, and the steel belt is left in to lend it strength. Powdered slate is then chemically bonded to the shingles, which are then attached in strips of seven to a thin panel coated with high-density polyethylene liner.

Almost all of the sections of the tire that aren't used in the manufacturing process are recycled as "grubble," a gravel substitute that's used as backfill for fiber optic cable and other applications.

According to Colip, Charles Reich, author of "The Greening of America," stated at a Tulane University conference that FlexShake has the highest use of a waste tire in the country.

The average roof, said Colip, uses 2,500 recycled passenger tires--roughly 4,500 square feet of roofing material. The FlexShake Web site features a house in Dallas that was covered with over 5,000 recycled passenger tires, or 9,000 square feet of roofing material.

As one would expect, the rubber roofs can stand up to a lot of pounding. It's particularly resistant to hail and wind-driven rain. State Farm insurance even offers a 28 percent discount on hail damage coverage for those who use it.

Durability is another selling point. Colip said that FlexShake has a 50-year life expectancy, compared to just 15 years for a wood shingle roof.

He added that despite being made from tire rubber, FlexShake shingles aren't vulnerable to fires. "The shingles are very hard to burn because they use the tread piece and not the (more vulnerable) side walls," he said.

Tread pieces are built with heat inhibitors; otherwise, said Colip, the tires on hard-braking cars would catch on fire.

The company has plans to test for a Class A fire resistance rating, but in the meantime, it carries a Class C rating. That's good enough for use in 99 percent of residential areas, said Colip. Untreated cedar shakes, by comparison, don't even qualify for a fire rating.

While FlexShake is installed like asphalt shingles, said Colip, it looks like much more higher-priced slate.

The shakes are an average of three-eighths inches thick, and weigh 350 pounds per square (100 square feet). That compares to 700 pounds per square for real slate.

But it's the installation of FlexShake that worries Mike Krause, the general manager at American Building and Roofing Inc. "I've seen samples of the product and I have some reservations about what I see....the roof product sample is face-nailed," which would leave the nails exposed to the elements.

Expansion and contraction around the nails, he explained, could draw in water and lead to fastener failure, leaving water to leak "all the way to the substrate."

FlexShake seems to be "depending on a very thin sheet to keep out the water," said Krause, referring to the polyethylene-coated panel.

According to Colip, the panel is underneath the shingles, leaving the roof with a watertight seal.

Krause, in turn, noted that new roofing products have a high failure rate when subjected to the Northwest's weather. "I'm not at all concerned about the rubber failing," he said, but FlexShake requires a round rubber tire to lay flat, and face-nailing would prove "an inherent weakness in the product."

Krause added, though, that he has only seen the samples that the company has sent him, and wasn't provided with application instructions.

"With proper underlayment and proper application," FlexShakes could be a very good product, he said. It was developed in Texas, however, "and the Northwest is completely different."

Krause has fielded inquiries about the product but has yet to sell it.

The FlexShake Web site lists Van Davis from the Vancouver area as the only distributor of the product in the Pacific Northwest.

"I'm always interested in new roofing products," said Krause, who appreciates its environmentally responsible attributes, but his concerns about the product would need to be addressed before he used FlexShake on his house or recommended it to someone else.

Previous columns:

• Builders, counties partner for green homes, 10-05-2000
• Modular construction goes to new heights, 09-28-2000
• Affordable housing to be studied at conference, 09-21-2000
• County trying to curb construction waste, 09-14-2000
• Nuprecon expanding its services and markets, 09-07-2000
• KJM rides transit boom, 08-24-2000
• Seattle Iron & Metal streamlines its operations, 08-17-2000
• More than meets the eye at 505 Union Station, 08-10-2000