While trends in design are as fleeting as drywall screws, roof designs are something people have to live with, especially when it's metal. This growing need for the distressed look appears in all parts of the country as the urban chic try to emulate the local environment: fishing shacks, old ranches, renovated factories.

There's a reason those old, funky buildings are still standing. It's the tin roof that looks like hell, but is still performing, in a sense, advertising its longevity for all to see. And those buildings have survived long enough to be revered for their rustic appeal that people now want to copy rather than destroy.

"Ten years ago, people would have thought you were crazy. It looks like a warehouse," laughs Bart Pride, of Threadgill Sheet Metal Works in Cypress, Texas. The company has been installing industrial-type roofing and siding in the Houston area since the 1980s, but has seen the trend explode recently. "It's a good looking product."

New Again

If it did, then the standard response was to replace or cover with a myriad of coatings geared specifically for industrial metal roofs. Of course a rusting panel with fasteners backing out is not doing its job, but signs of rust or age were often portrayed as failures. Coupled with the architectural metal roofing industry's concerted effort to distance itself from the industrial setting, corrugated or structural panels were replaced with more modern and watertight profiles.

Threadgill Sheet Metal Works is a second-generation metal roofing company that found itself riding a recent wave of customers who want a post-modern industrial look for their homes and businesses. From corrugated to R-panels to U-panels, a trend emerged with the redevelopment of industrial areas in western Houston. The West End Tin Houses movement has given so much cache to industrial siding that Threadgill recently finished enveloping a $400,000 single-family home in the Houston suburbs.

"It's all corrugated galvalume roofing and siding," says Pride. "Down in that area, everyone is going with metal roofs and metal siding. It's kind of an urban chic thing. That area is just booming with it."

Another irony in the movement is that a maintenance concern is being engineered into one of the roofing industry's most durable materials. The exposed fasteners use a neoprene rubber washer that is unlikely to last as long as the panels. Pride does go over that reality with building owners and designers, but admits that the 15-20 year grace period doesn't register that strongly. As a measure of insurance, all Threadgill roofs get a self-adhered membrane underlayment.

Pride credits the recent surge to consumer demand as well as an improvement in the finishes that pleases the designers. Some create their own patinas or can outlast most conventional roofs. Recently, there's been an interest by some restaurants to have rust appear on newly installed roofs.

"I've talked to some people that are looking for that," says Pride. "It makes you wonder, but once it's in place you can understand why."

Rust or Bust

"They want it to look like old ranches and mining homes that have been there forever," says Johnson, who liked it so much he has corrugated Cor-Ten on his house. He believes that the style seeped in several years ago from Colorado, where high-end resorts started to incorporate the surrounding architecture, which was definitely function over form. By updating elements and inserting better engineering and design, the idea was to give new developments a sense of continuity and place.

"They're just trying to get their homes to blend in with the surroundings," says Johnson. "It goes with the rocks and soil, even the trees."

His own house sports juniper siding that is acquiring its own aged appearance. Johnson also offers an exterior wainscot from Cor-Ten. His display areas in Belgrade and Billings showcase examples of his products, inspiring old timers to tease him about selling rusty metal. In fact, Johnson is almost apologetic when describing something that is designed to look, well, run-down.

"It looks better than it sounds," he says, adding that one good rain gets the metal started. "It gets pretty dark in a year. A good way to accelerate it is with a salt water and vinegar solution."

Johnson offers no warranty on the product. In fact, the copyright holder of Cor-Ten, US Steel, recommends on its Web site that it NOT be used for roofing and siding. However, many commercial skyscrapers - including US Tower in Pittsburgh, circa 1970 - are clad with Cor-Ten, which is also a favorite material for artists who appreciate the product's natural oxidation properties. Its originators would prefer more traditional uses like interior framing, bridge support and cargo containers. This apparently doesn't deter consumers who may not only be getting something that looks old, but acts its age too.

Rust Never Sleeps

Although Gwen Howell, a partner in Recla Metals, says that her product can last as long as 50 years in the dry climate of the West, the company offers no warranties because it doesn't do installations and has seen some real design concerns over the years. Still, the customers want the look. "They know the risk they take. We do our best to assure them," says Howell.

Her company has seen plenty of design problems associated with a "rusty roof," the term the company actually uses to promote its products. From gutters that hold water to products that produce toxic run-offs, Howell prefers to remain in the fabrication end and let the market dictate demand. The product, containing a range of recycled materials, comes from several vendors and the oxidation process of the 22- or 24-gauge panels is engineered purposely into the product. Howell says that the relatively heavy panels have sufficient thickness to last the elements, provided the design sheds the precipitation quickly. She is also aware of the irony in embracing a look that many used to abhor.

"For years the roofing industry has been trying to prevent rust. It's just a change in trends," says Howell. "It's originally based on a galvanized barn tin that's 100 years old. We just designed a product that rusted quicker than putting acid on a galvanized roof. I'm certain that there are people that are going to enter the market."