Dissimilar Metal Corrosion in Roofing Installations
This Technical Bulletin provides guidance when working with different metals used in roofing installations. Most metals used for construction projects are chosen for their strength, corrosion resistance and longevity. However, some metals do not perform well when placed in contact with specific other metals or exposed to certain chemical compounds. Users should be aware of compatibility issues and situations that may affect the performance of the installed roof.
Being aware that dissimilar metal corrosion potential exists and understanding how galvanic reactions take place will help in the selection of metals used on roofing installations. Potential problems can be eliminated before they occur; saving money and time while extending the life of a roof.
Before different metals are specified for a metal roofing project, it is advisable to consult with the metal panel manufacturers to determine if galvanic corrosion is a threat. Fastener selection is equally important as this could also lead to dissimilar metal corrosion.