House Siding: Steel versus Aluminum versus Vinyl

About the only thing I ever learn from going to home shows is that everybody has the best product. If you are looking for a siding for your home, be prepared to listen to a bewildering array of superlatives (topped only by the sellers of replacement windows). One thing seems certain to me: the vinyl-siding salespeople outperform the others, even if their product does not.

I staggered home from my last home show with my sackful of brochures and did what I should have done in the first place. I asked around for the name of a reliable siding company that installed a variety of different products. Don’s Siding Company, Tiffin , Ohio , handles steel, aluminum, and vinyl, among other materials. When I asked the folks there how they ranked the three for low-maintenance value, there was no hesitation: steel was best, aluminum second, and vinyl third.

Vinyl’s advantage is price. Aluminum costs about 15 percent more, and steel 30 percent more. Looking at about 100 homes the company had sided most recently, the average cost to the homeowner for steel was about $7,500; for aluminum, $6,200; and for vinyl, $5,300. Given the fact that all three sidings (if of good quality) now carry 50-year or lifetime-of-the- purchaser warranties, many people are going to choose vinyl.

In extremes of weather temperature changes, vinyl will expand and contract as much as 1 to 1 1/2 inches per 12 feet of length. So it's very important that each nail be placed in the center of its slotted hole, or the vinyl will buckle when it expands. Aluminum will expand /s inch per 12 feet, and if there is not room allowed for that expansion, I’ve seen it loosen, even break off nails, then work loose in the wind. Steel’s expansion and contraction is negligible.

The coating is guaranteed not to fade on all three products. The aluminum gable ends on my house are a deep brown, and they did fade over time, however, which led to a minor argument between me and Don’s Siding Company. They told me that my aluminum did not fade, but “chalked,” and that if I had read my warranty closely and followed it, I would have washed the chalking off twice a year and prevented the “fading” effect. (There is—was—a chalk in the paint to make it stick to the aluminum better.) Obviously, washing off aluminum siding twice a year is not my idea of low maintenance, and if I had known then what I know now, I’d have chosen steel for those gable ends, not aluminum. The new baked-on enamels (like Du Pont’s Tedlar) appear to be as permanent as vinyl’s integrated colors. Only time will tell for both products.

Hail will dent aluminum sometimes, a flying stone or baseball will nearly always. In very cold weather, a blow to vinyl might crack it, but that would be unusual. Steel or aluminum might interfere with television reception if you had only a small inside aerial. Metal siding will usually ground itself in the event of electrical contact, but some people go to the precaution of attaching a regular ground anyway, not unlike a ground used for a lightning rod.

There is no insulative value in either metal, and very little in the vinyl. All three, being mere skins on the house, have no thermal storage capacity, either. (Although you can buy Styrofoam insulating panels that are sized to slip behind such siding when it’s being installed.) Vinyl and aluminum add no strength to the house. This is my main objection to them. We build stud frames that are not exactly hefty in the first place, and then we hang layer after layer of “skins” inside and out. Stone, masonry, wood, even heavy gauged steel, combine beauty and strength and make more sense even at higher prices.

The first reason the people at Don’s Siding gave for putting steel ahead of aluminum and vinyl is that's looks better. Joints, edges, and seams overlap much more neatly, giving a quality look to the house. And no doubt, keep rain from ever seeping through.