The Advantages of 26 Gauge to 29 Gauge Metal Roof

Roof Support

• Roofing made of 26-gauge metal roofing is roughly 25 percent thicker than that of 29-gauge metal. Corrugated waves, ridges and valleys give added support to metal panels, but 26-gauge metal with the same design will always be stronger and more robust than 29-gauge metal. You can safely install rugged 26-gauge metal over horizontal supports called purlins, but you should install thinner 29-gauge metal only on plywood or other solid wood decking. If you do install 29-gauge metal over purlins, the purlins should be closer together than required for heavier 26-gauge metal.

Effect of Wind

• Roofing made of 26-gauge metal can withstand uplift caused by high winds better than 29-gauge metal can. If you live in hurricane country, you should use 26-gauge metal. To withstand the same wind force, you need to put the clips closer together on 29-gauge metal than you do on 26-gauge metal.

Hail and Snow

• The appearance of 26-gauge metal roofing will suffer less from battering by hail stones or other falling objects than 29-gauge metal. Twenty-six-gauge metal also can bear heavier loads than 29-gauge metal. If you live in an area with occasional large hail or heavy snowfall, 26-gauge metal is the better choice.

Thickness and Weight

• Weight may be an issue depending on the robustness of your roof support. The weight and thickness of metal roofing varies by the type of metal. Twenty-six-gauge sheet steel is .0179 inch thick and weighs .750 lb. per square foot (psf); galvanized steel is .022 inch thick and weighs .906 psf; stainless steel is .0187 inch thick and weighs .756 psf; and aluminum is .0159 inch thick and weighs .224 psf. Twenty-nine-gauge sheet steel is .0135 inch thick and weighs .563 psf; galvanized 29-gauge steel is .017 inch thick and weighs .719 psf; stainless steel is .0141 inch thick; and aluminum is .0113 in. thick and weighs .160 psf.