Metal Roofing 101: Galvanic Corrosion and How to Prevent It

When you’re considering metal roofs for your roof replacement project, chances are your roofing contractor has told you that it’s one of the most durable roofing materials out there. If so, you should know that it’s not exactly true. In fact, it’s entirely possible for a metal roof to face one recurring problem, and that’s galvanic corrosion.

Lead

As your roofers will tell you, galvanic corrosion in your metal roof will occur if the metal of the roof comes into contact with another metal in the presence of electrolytes like water. One of the most common metals that can trigger galvanic corrosion is lead, especially if it’s used in a pipe penetration that protrudes from your metal roof. To prevent this, you can either have your contractor make sure that lead doesn’t come into contact with your roo,f or you have the metal roof coated in Galvalume® coating.

Copper

Another kind of metal that can kickstart galvanic corrosion is copper. Your roofing contractor will tell you that this is a type of metal that doesn’t exactly react well with galvanized metal panels to the point that even trace amounts should be avoided to prevent your roof from corrosion.

Graphite

Graphite is the material used in pencils and, surprisingly enough, is extremely corrosive to the aluminum and aluminum alloys that are used to create metal roofs. Since some contractors tend to write on a metal panel of a roof with graphite pencils, the element can eventually eat through the Galvalume coating and rust the metal roof itself. With that in mind, always tell your roofer to use a sharpie or grease pencil if they need to write on your roof.

Make your search for quality roofing companies easier by turning to New View Roofing. We are your leading provider of residential and commercial roofing services. Give us a call at (469) 232-7220, or fill out our contact form for a free inspection.