Aluminum VS. Steel

Seamless aluminum gutters have a great image. They’re modern, quickly and easily made at the jobsite, even cut to order from a coil of metal that’s fed through a portable machine.

By comparison, what are steel gutters? Aren’t those the kind of gutters that seamless aluminum was meant to replace? More often than not, the image of steel gutters may be the rusted and peeling relics that were pulled off the house to make room for aluminum.

But wait. Those old gutters may have been only galvanized steel, perhaps painted onsite by the installer or homeowner. In contrast, steel gutters are being made today “that provide some great improvements on coatings and paints, so they resist corrosion and hold their color,” reports Nick Rich, president of Skyline Enterprises, a manufacturer of gutter products and coil based in Wheat Ridge, Colo.

Rich believes gutter installers should take a second look at steel. “It has twice the tensile strength of aluminum, and half the amount of thermal expansion and contraction. So you get a really durable gutter, which is important on any home and especially in areas where wind and hail and high snow loads are a problem.”

Installers who “see those old red-rusted steel gutters,” Rich continues, “need to realize that simple galvanized steel is different than today’s Galvalume.” He recalls how his father founded a Denver gutter business in the 1960s when seamless aluminum came onto the market, but then switched to steel in the 1980s when aluminum prices became volatile and subject to spot shortages.

Having seen how steel gutters had proven themselves a viable option, Rich founded Skyline Enterprises in 2004 as an opportunity to distribute a new generation of products with Galvalume/Zincalume substrates and today’s inorganic paint coatings that resist fading and chalking.

“The substrate for our steel gutter coil is a corrosion-resistant, hot-dip aluminum-zinc alloy coating that consists of 55 percent aluminum, 43.4 percent zinc, and 1.6 percent silicon,” explains Rich. “So you get the barrier protection and long life of aluminum, plus the galvanic protection of zinc at cut or sheared edges. Our coil is also pre-painted with a modified resin paint system that uses ceramic and other inorganic pigments.”

Rich admits that steel is heavier than aluminum, such that .027 aluminum is half the weight of 26-gauge steel. “The additional weight can be an issue for gutter installers when they first start using steel,” he says. “But depending on your market, steel can give you a gutter that differentiates you from the competition. We’ve seen steel gutters installed in the Arizona desert because of their overall durability and the UV-resistance of the paint. Yet in areas with snow and ice, steel can give you a stronger and better product than aluminum.”

Steel coil can be run, and has been successfully run for many years, through standard portable seamless gutter machines. “Machines based on older designs may require you to adjust the machine for steel versus aluminum,” Rich advises, “but on some of the newer machines, adjustment might not be needed.” While aluminum gutter coil comes in thicknesses of .027 and .032 inches, he says 26- and 24-gauge steel are the equivalent to thicknesses of .019 and .024 inches, respectively. “Zinc galvanization can also rub off on the rollers and need to be cleaned,” he adds, “though our paint coating eliminates that problem.”

Rich acknowledges that steel prices have risen in recent years. But he points out steel prices stabilized in 2006, while aluminum prices have a long-term history of rising faster than steel. “Market prices for both metals are fairly calm right now,” he reports, “so that steel is not rising in price relative to aluminum. Though aluminum gutter coil can have a nominal price advantage, steel can be price-competitive and sometimes even cost a little less than heavier-gauge aluminum.”

Skyline Enterprises sells both aluminum and steel coil, though it has specialized in the latter as a way of differentiating its products in the market. “I really do believe the steel gutter market will grow,” he says. “It’s a quality product, and it’s a ‘green’ product because steel is made of recycled content.”

To gutter installers who are thinking of giving steel a try, Rich counsels, “Different is always difficult at first. But steel gutters are easy to install. Though steel weighs more than aluminum, there really is no appreciable difference in how much time and labor it takes to install.”

One Installer’s Experience
One installer who agrees with that assessment is Tom Tufts, owner of TNT Rain Gutters in Sacramento, Calif. “With steel you may have to push the drill a little harder, or push a bit harder to crimp the ends,” he allows, “but otherwise it’s about the same time to install a steel gutter as an aluminum gutter.”

Through his four years in business, Tufts reports that his company has only been called upon three or four times to install aluminum gutters. “There’s just not much call for them, because aluminum can bend even when the wind hits it,” he explains. “Steel is a lot stronger — and if both the outside and the inside of the trough are coated and painted, steel gutters can last a very long time.”

As proof, Tufts says his own 1945 house still has its original steel gutters. “I don’t get many calls for replacement gutters from homes that were built in the 1930s, ’40s, and ’50s,” he continues. “Most of my jobs are on houses that are 10 or 15 years old” and were fitted with aluminum gutters, he says.

Because TNT Rain Gutters is a small operation, Tufts has found that steel gutters have suited his business in another way. “With aluminum I’d need to buy a machine,” he explains. “But I chose not to go that route because of the cost of the machine and because I had no place to park it. Also, if you use a seamless machine then you’re stuck with only being able to install the style of gutters that your machine is designed to make.”

Instead, Tufts buys sectional gutters from Award Metals of Baldwin Park, Calif. In that way, he can order steel gutters in 25- or 30-foot sections according to the style needed for each job: plain fascia, curved fascia, ribbed tile fascia, half-round, and K-style. “That gives me more flexibility to do customized jobs and sell rain gutters to different clients, from small houses to large commercial buildings,” he relates.

His customers include home developers, which Tufts describes as “the bulk of the market for steel gutters.” Builders choose the material because of its high strength and durability, which reduces complaints and call-backs, but at a price that is competitive with aluminum. “You can even make steel gutters a selling point,” Tufts adds, “because they’re an upgrade from aluminum, but at a much more affordable cost than copper.”

The Commercial Angle
If steel gutters are winning some converts in the residential market, the metal already enjoys a solid following for commercial buildings. Harry Schouten, estimator for Advanced Architectural Sheet Metal in Chicago Heights, Ill., says his company offers commercial and industrial gutters in both 24-gauge steel and .032 aluminum. At those thicknesses, he reports, “the steel can actually cost less than the aluminum.”

The two metals sold by Advanced account for 90 percent of gutters installed on commercial buildings. “That’s because commercials roofs are expected to last 20 years,” Schouten relates. “After that, it’s cheaper and requires less labor to just take off the roof and the gutter at the same time and replace them both at once. So the gutters have to last as long as the roof does.”

Schouten says steel gutters, because of their greater tensile strength, are used more frequently than aluminum on commercial jobs. The one exception, he allows, may be in coastal regions where salty air can corrode the raw-cut edges of steel gutters. On the other hand, he observes the increase in standing seam metal roofs for commercial buildings is driving more architects and builders to specify steel gutters for those projects.

Like others, Schouten confirms that today’s steel gutters are a different breed than the galvanized steel gutters of old. “The Galvalume steel gutters on the market now don’t rust like the old gutters,” he states. In addition, the commercial gutter market differs from the residential market in one important respect.

Since gutters for homes must be consumer-priced, coil manufacturers must use paint systems that represent a compromise between performance and price. But commercial gutters must last as long as the roof, so that top-of-the-line Kynar 500 paint system is the standard paint coating. “That also makes a big difference in resisting corrosion,” Schouten says, “and makes steel the preferred choice for most commercial gutter systems.”