Standing Seam Vs. Corrugated Metal
The two most common choices for a metal roof are corrugated metal and standing seam. Standing seam roofs are generally made from thicker grades of steel than corrugated steel roofs. While many corrugated steel roofs are made using a very thin 29 gauge steel, a minimum of 26 gauge galvalume steel is used for manufacturing of standing seam panels. A 24, and 22 gauge steel can also be used for residential and commercial styles. A metal coil from which standing seam panels are manufactured is usually factory painted with a high-end Kynar 500 paint finish. Corrugated metal roofs are often painted with cheaper acrylic paints. Both styles are available in a rainbow of popular colors, much more than asphalt shingles. The clean lines and unexposed fasteners of a standing seam roof are considered more attractive and earn the bulk of the residential trade. Metal roofs are almost, but not quite, maintenance free with corrugated roofs requiring a bit more attention to tend to exposed fasteners.
Maintenance
While metal roofs can last for centuries, the coating on metal cannot. This could lead to the need for painting or re-coating in areas subject to harsh weather and acid rain. In the meantime, a metal roof can be kept looking fresh with just a regular hose down. Also, the fasteners on corrugated metal roofs should be re-tightened and re-caulked about every ten years. Standing seam has an improved design featuring concealed fasteners. Raised seams, with no roof penetrations, help minimize the chance of a roof leak down the road.
Warranty
Galvanized steel roofs typically carry warranties of up to 50 years. While metal roofs cost more than asphalt shingles up front, they will last three to five times longer. While you may not be staying in your house 50 years the presence of a metal roof will enhance your asking price at sale time as the next owner will not have to worry about installing a new roof anytime soon.
