Galvannealed is carbon steel coated with zinc/iron alloy on both sides
Galvanized steel is cold-rolled carbon steel with a zinc coating on either side. The zinc provides great corrosion resistance, but it does not provide a great paint surface. It can be painted but only after the metal has been exposed to the elements for a period of time. It can be painted sooner with a pretreatment. There is another coated product that is more suitable for immediate painting — Galvannealed.
Galvannealed is carbon steel coated with zinc/iron alloy on both sides. The zinc/iron alloy allows for better paint adherence. The iron in the alloy coating provides something for the paint to “grab onto.” It is a product that is intended to be painted, and should not be left unpainted, especially when exposed to the environment. Galvannealed is sometimes mistakenly referred to as “paintgrip”, which is a trademarked term for another paintable, more expensive product which has a zinc-phosphate coating. Galvannealed is not technically “paintgrip”, but it will “grip paint”. The zinc\iron coating weight is denoted with an A40 or A60, which means .40 or .60 oz./sq.ft.
