Over the last several years, metal roofs have grown increasingly popular with consumers. The Metal Roofing Alliance (MRA), a nonprofit association of metal manufacturers and contractors, estimates metal's share of the roofing market at around 8%, with a projected 1% annual growth.

In the past, sales of metal roofs for single-family homes were concentrated in regions where specific conditions demand a utilitarian approach to building. Metal roofs are fire resistant, hold up well in storms and against hail, and shed snow easily; the southeastern hurricane coast, western wildfire zones, and snow-heavy areas in the west and northeast have historically seen the majority of metal sales. Now, however, thanks in part to a public relations blitz by the MRA and the growth of mainstream demand for green products, metal roof sales are expanding nationwide.

Contractors have taken up the banner, too.

SPREAD THE WORD Les Deal, a veteran remodeler from Cedar Rapids, Iowa, has offered aluminum roofs to his clients for years, but recently intensified his focus after growing tired of the waste associated with asphalt shingles. “I was finding that too many homes are being neglected in that area. People are too often replacing roofs,” Deal says. “It's an area of need.”

Proponents such as Deal are quick to point out the potential durability of metal roofs. Installed properly, a metal roof can last for decades, perhaps even a century in the case of aluminum or copper. That durability is driving sales, says MRA president Bill Hippard. Aging baby boomers are turning to metal, he says, hoping that their next roof will be their last.

Metal roofs are also popular with green-building advocates. Improved kynar paints have boosted reflective performance, helping cut utility bills. Also, most metal roofs include recycled materials, and can be recycled themselves; and because metals are lighter than other materials (aluminum can weigh as little as 40 pounds a square) many systems can be installed directly on top of existing roofs. All of those factors greatly reduce the waste associated with shorter-life asphalt shingles that tend to wind up in landfills after they're removed.

A keeping-up-with-the-Joneses factor is helping sales, too, says Michael Strong, president of Brothers Strong in Houston. Metal is expensive, different, and in the case of standing seam, sleek and modern. Strong just completed his company's first metal-roofed project, but he says metal is definitely hot in Houston. Based on what he's seen locally, Strong says, “the tipping point is the sex appeal. A lot of people will say they're doing [metal] because it's green, but more people want it because it's expensive and looks cool.”

IT KEEPS ON GOING With the market strong and, in much of the country, not terribly crowded, metal roofing might seem like a great way to expand, stake out a niche, or differentiate by offering a product the competition doesn't have. But Deal and others with similar experience warn that metal is an entirely different roofing system requiring a unique approach to installation.

Because the material itself is so durable, metal roof systems are designed with an eye toward the long view. Most are manufactured and sold as complete systems, with components such as seams, fasteners, and flashings, designed to shed water without relying on sealants. Installed properly, a well-designed metal roof system should be highly durable and effective, lasting for decades with little or no maintenance; at the same time, the system is less tolerant of installer error, leaving little room for fudging or improvising a quick-fix.

Asphalt roofs are more forgiving, Deal says; by the time a mistake shows up and causes problems, it's time to replace the roof anyway. An aluminum roof, however, should “last a century,” Deal says. “Screw up and you're going to have to start over or do something serious. Your attitude has to be different.”