In the installation of a metal roof, the types of metals used in the process must be taken into account. Dissimilar metals can have a negative effect on the longevity and integrity of a metal roofing system. With respect to the panels and fasteners, proper metal combinations will ensure a durable, secure metal roofing system for many years to come.

Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially when it is in contact with another metal in the presence of an electrolyte. Water is considered a weak electrolyte. Therefore, in the installation of a metal roof, water would be the catalyst. For example, steel panels used in metal roofing are coated with a zinc/aluminum coating (galvalume). This coating effectively protects the steel from corroding. The galvalume coating, commonly used in the metal roofing industry, has replaced the galvanizing process. Thus, ensuring a more effective method of deterring unsightly corrosion.

The use of specific types of metal panels is well documented and reputable metal panel manufacturers will assist in metal type choices for metal roofing installation. Primarily in areas of high saltwater exposure, i.e. beach fronts, high salinity brackish water environments, aluminum would be the preferred metal panel type. In areas of less exposure to saltwater, steel panels would be used – galvalume.

Attention to detail is crucial in the installation of a metal roof. To avoid the possibility of a galvanic reaction and thus decrease the life of a metal roof, proper attention to the metals involved is critical.

Attention to detail is one of the hallmarks of a Roof Duck metal roof. Our complete metal roof installations are comprised of premium metal roof panels coupled with accessories of equal caliber. We look forward to working with you on your next metal roofing project!

Give The Roof Duck a call @ 904.345. 0663!


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