CSSBI SSF 33-11: Wet Storage Staining of Galvanized and Galvannealed Steel Sheet

Introduction Most cold formed steel building products, whether painted or unpainted, are manufactured from a sheet steel material that has some form of metallic coating applied. This metallic coating can be zinc (galvanized), zinc-iron alloy (galvanneal) or a 55% aluminum-zinc alloy (GalvalumeTM). The metallic coating is available in a range of thicknesses to provide the degree of corrosion protection and service life required. One of the concerns expressed by installers relates to the presence of wet storage staining on the products, how this staining impacts the long term performance, and what can be done to remove it. The purpose of this fact sheet is to address some of these issues, allay some fears, and give guidance on proper storage techniques.