Facts on the Hot Tin Roofs

• By Julie Sturgeon
• 06/01/08

As chairman of the Metal Initiative, Sid Peterson fields his fair share of phone calls inquiring about metal roofs these days.

“It’s pretty incredible particularly in light that my company doesn’t make metal roofing,” he says. Historically, it’s been a premium product, the kind of topping Thomas Jefferson chose for his Monticello plantation in Virginia more than 200 years ago. Then retail giants like Gander Mountain hit the scene with their distinctive green metal roofs, and folks began to remember this option. The number of qualified installers increased, and the momentum began rolling.

“The design community and building owners are coming to the conclusion that maybe I need to look at this again because it can’t be expensive or I wouldn’t be seeing the growing applications I’m seeing now,” Peterson points out.

Certainly it’s popping up in school districts across the country. When Corvallis School District #1 in Montana added to its gymnasium at the high school in 2000, officials told the contractors to cover not only the addition but the original structure with a metal roof — a move it has repeated several times on various building projects since then. Likewise, when the new Robert C. Cooley Middle School opened in Roseville, CA in 2001, architects had ensured the campus's unique look was included in the roof systems' designs. The campus’ 13 buildings feature cone-shaped turrets, tapered metal panels, and radius roof systems, as well as dormers and other architectural features. Even as late as last week, the request for bid specifications for the Spring Creek Elementary School roof refurbishment in Paisley, FL, called for metal.

Why the Buzz?
Anything green grabs the headlines today, so it’s no surprise manufacturers lead off the benefits list with metal roofs’ earth-saving traits. The actual steel or aluminum itself is typically made from 60 percent recycled materials, according to Bill Hippard, president of Metal Roof Alliance and vice president of sales for Precoat Metals in St. Louis, MO. Once on, it’s durability is measured in centuries, although the typical warranty covers 40 years.

Meanwhile, asphalt shingles generate 20 billion lbs. of waste in landfills annually. “You could line up trailers from San Francisco to New York and double back to Chicago with that,” says Hippard.

Energy also triggers enthusiastic numbers. Take, for instance, the case study Carrie Miller, The Metal Initiative’s vice chair and marketing manager for Whirlwind Building Products, likes to cite: Two elementary school buildings in Paulding County, GA, with identical layouts, thermostats controlled at the district office, electric HVAC, and gas-fired heating. Bagget Elementary installed a standard roof, Poole Elementary chose a metal version. After one year, Bagget’s energy bills totaled $8,054 more. (Poole’s gas consumption was actually $750 higher, but the electricity costs more than made up for that in the long run.) That was in 2004; by 2007, Poole’s savings had risen to $14,496.

College buildings, experts assure, should enjoy the same proportional cost reductions.

Sure, the traditional vertical seam panels are still available, but in 2008 metal’s versatility is so great, many observers can’t tell it apart from cedar shake, tile, or asphalt. Metal panels are also unique because of their ability to curve into whatever esthetically pleasing look the campus wants, and it can be transitioned from the roof directly to the wall to achieve an overall seamless look.  Paint them and you not only add visual interest, but you added pigment with heat reflective capabilities strong enough to cook an attic by 25 to 40 degrees, Hippard notes.

Metal is lightweight (roughly one-third of an asphalt shingle), so it won’t add to pressure that can cave in roofs during earthquakes, and it’s fireproof, which adds to a building’s safety column. In colder climates, they help with snow melt off, and can withstand hail with only cosmetic damage. Some manufacturers have begun offering pre-distressed panels to hide dents and dings as part of the design.

But although these performance standards are inherent in the product, it’s a mistake to assume that in your request for bid proposals, warns Sid Peterson. If you specify it must be able to withstand a hailstorm in accordance with AFTM1102, for instance, this puts any future problems on the manufacturer’s shoulders to address. Leave that out and the school is on the hook for the repair bill.

“Nobody is trying to duck out of anything here, but you need to tell us what you expect this roof to do,” he explains.

It’s Not True
Still, many school board members still buy into the notion that metal roofs are notorious for echoing the ping, ping, ping of raindrops. That myth, assures Miller, comes from old barns that were built with steel roofing installed on open purlins (or post frame) with no insulation. Today’s metal roofing is typically installed over plywood and felt, or even an existing roof, so rain here sounds similar to any other surface. Hippard has done decimeter readings on metal roof buildings, and the measuring tool picks up only slight differences below the human ear’s capability to catch.

As for durability, it’s a famous line in the B52s’ Love Shack: “Tin roof. Rusted.” Sing it with gusto, but don’t believe it, Hippard says. Thanks to technology and paint with corrosion resistance, “I have even talked to our attorneys, and they don’t have any problem saying that a painted metal roof is the only product that will outlast its warranty,” he notes. West Virginia-based Follasbee’s extensive metallurgic research means its metal roof selections don’t even need paint to withstand severe corrosive conditions such as salt-water environments. Over time, it weathers to an attractive gray patina.

Finally, some people mistakenly believe metal roofs attract lightning. Nope, experts say. In fact, physicists can prove they defuse a strike over a larger portion of the hot spots and reduce the danger impact.

But rumors that they cost more upfront aren’t exaggerations. Some insiders say residential costs are higher per square foot when compared to the materials they typically choose from, but commercial accounts that deal more with cedar shakes or clay tile will find the quotes more competitive.

Take into account, too, that the more complex your roof, with dormers, HVAC outlets and so forth, the higher the skill level you need to install the roof. That alone certainly adds to the upfront costs. But advocates like Hippard still have the facts on their side. When he served on the school board in a Pittsburgh suburb a few years, it fell to that group to allocate a $30M renovation budget wisely. “We started with the floors in the classroom, then windows, desks, labs, lighting, and by the time we got to the roof, no one wanted to talk about it,” he says. That is, until he pointed out that the existing roof contained asbestos, and the lightweight metal could be installed right on top and encapsulate the dangerous material. The fact they suddenly had lower energy bills was a welcome perk.

“Installing a metal roof is one of the most cost effective things any school can do,” Miller insists.