Installer on a Hot Tin Roof

Metal roofs are gaining popularity, but there's more involved in installation than meets the eye.

Source: REMODELING Magazine
Publication date: May 1, 2007

By David Zuckerman

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

Working with metal roofs requires patience and precise geometry, which, ultimately, slow the installation; a complex installation can last as long as three weeks.

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.”

GOOD ENOUGH IS NOT ENOUGH

Standing-seam roofs can add a sleek profile that stands out in neighborhoods where shingles are common; metal shingles offer the benefits of metal while retaining a traditional feel.

Gene Walton, head of quality control at American Metal Roofs in Livonia, Mich., says that an installer, whether single-line or full-service, must think quality all the way, down to the underlayment.

“[We use] a synthetic 3-ply system woven for strength — it lasts an extremely long time,” Walton says. “With metal, there will be condensation, so you need a premium underlayment.”

Alex Biyevetskiy, co-owner of L/A Roofing, a metal specialist in New England, says measuring precisely is essential to keep the roof's lines as true as possible. Panels, flashing, and seams interlock; any one inconsistency can compromise the entire roof's integrity. “With metal, you have to make sure you're very precise with your geometry,” he says. Flashing details, dormers, valleys, and other such elements can be tricky with metal.

Flashing often has to be cut on-site to fit a particular detail, as do metal shingles that meet roof elements. Walton says that when his crews install valleys, the shingles abutting the valley are turned with a metal break, to lock into the valley pan. “Each individual shingle that hits that valley has to be hand-formed, hand-shaped to fit,” Walton says. “With asphalt, you're used to using tar and simple flashings; [with metal] you're talking about a roof on there that's permanent. The flashings are handcrafted —they're made to be there for a hundred years.”

All that detail work and on-site crafting takes time; metal roof installations can take up to three to four times as long as a typical asphalt shingle job. The greater the complexity of the roof, the longer the job. Houston remodeler Strong was surprised to find on a recent project that the installation of a Berridge standing-seam aluminum roof (the first metal roof he'd ever done) took three weeks to complete. Strong, who subcontracted the job, says he thought “they'd have it done in two days.”

Deal estimates five man-hours per square on a typical aluminum roof installation compared with a conservative two hours on a typical asphalt job. “With metal, you have to take the time to get your measurements right. When you're budgeting your time, you don't think at all the same way you do with asphalt.”

Plan on a lengthy installation, Deal says. “You can end up working really cheap on a job if you're not careful.”

SORTING IT ALL OUT

With so much involved, some remodelers won't touch a metal installation with their own crews. In New Hampshire, where heavy snow loads have made metal popular for years, Tom Avallone's Cobb Hill Construction has remodeled and built a number of commercial and residential metal-roofed projects. But he never does the install himself. “Sub it,” Avallone says. “Don't do it yourself. If you don't know how to do it, don't get involved.”

For full-service companies that do want to learn and control the process, Deal recommends focusing on a limited range of products and choosing a manufacturer that has an established track record and can provide factory or on-site training. Each manufacturer's installation process is proprietary and unique, so experience with one isn't necessarily transferable to another. And brands with a long history of producing a certain product often discover best practices that aren't necessarily intuitive.

“Don't assume you know one product because you've worked with another. You have to respect every brand's material and how it functions,” says Deal, who uses aluminum shingle and standing seam products by Classic Metal Roofing Systems.

Deal says he prefers aluminum because it's lightweight and won't rust under any conditions. And because steel requires galvanization, carrying it means an additional layer of variables to consider in selecting a product.

“You have to know how that steel is made, how it's coated, how thick the galvanizing is, and whatever else is on it,” Deal says. “Steel is totally dependent on the coatings. So you must know a lot [about the product].”

Steel is also more sensitive to scratching than aluminum, which makes it susceptible to rust because protective coatings can be scratched off. However, Biyevetskiy says, “steel is the most widely used roofing material in the industry because it is more affordable and still provides really good quality and longevity given a proper installation.” —David Zuckerman writes frequently on construction topics from his home in Brooklyn, N.Y.

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