Galvalume Versus Galvanized
Junnan’s nationwide team of architectural sales reps spend a considerable amount of time each year counseling architects on which standing seam metal roofing systems, products and profiles might work best for their design projects. One of the questions most frequently asked by architects is: What are the differences between Galvalume and Galvanized Steel Plate when used in roofing. It comes up so often, we thought we’d take a few minutes and use this blog to explain those differences.
First, a little bit of background. Galvalume® was invented by Bethlehem Steel in 1972. It is a trademarked name, but many people use it as a generic term to describe a metal roofing product consisting of steel coil coated with a metal alloy. That alloy is 45% zinc and 55% aluminum and looks similar to galvanized steel, but the visible crystals are smaller and close together, giving it a smoother appearance. Galvalume has a cousin, Galvalume Plus. The only difference is Plus has a thin, clear acrylic coating. Because Galvalume Plus can be roll-formed dry without vanishing oil, it is very easy to form and install safely.
The combination of zinc and aluminum in Galvalume enhances both the positive and negative effects of aluminum. Galvalume has barrier corrosion resistance and heat resistance similar to aluminized material and good bare edge galvanic protection and forming qualities like galvanized material. Consequently, Galvalume and Galvalume Plus will resist rust, the elements and fire while providing a sturdy and protective covering.