Nearly all steel has a protective coating to prevent corrosion. Normally the term used is “galvanized steel”, but that’s not an accurate description of this coating.
Galvalume is a tough, durable coating that consists of zinc, aluminum and silicon. It is created using a 55% to 45% ratio of aluminum to zinc alloy with a small amount of silicon to ensure durable and even adhesion.
Galvalume is used to protect iron-based alloys that are prone to rust and corrosion. Galvalume coated steel protects the underlying steel from oxidation. Galvalume is applied to both sides of cold-rolled steel sheets using a hot-dip process that protects edges as well.
The aluminum is what differentiates Galvalume from galvanized steel. Galvanized steel only includes the zinc alloy. As the coating on galvanized steel wears down or deeply scratched, corrosion begins. This corrosion will eventually cover the entire surface and the steel beneath will shed the galvanized layer.
Why aluminum and zinc? The aluminum (which naturally resists corrosion) coats the steel and acts as a barrier protection, whereas zinc provides self-healing properties against scratches. The zinc also acts as a sacrificial layer prolonging the life of the steel underneath. Zinc creates a barrier to moisture. Aluminum also keeps any corrosion in a damaged area from spreading to the rest of the panel.
Galvalume is primarily used because of its corrosion resistance, but there are other factors that will persuade you to consider it.
Corrosion resistance. As we discussed above, steel coated with Galvalume contains aluminum which is naturally corrosion resistant. Galvalume protection far outweighs that of galvanized steel.
Weight. Galvalume does not add a significant amount of weight to the steel. The coating is flexible and will not crack or flake as the sheet metal is bend or formed.
Energy Efficiency. Steel coated with Galvalume provides superior reflectance in the sunlight. High reflectance reduces heat absorption through the roof panels. With appropriate insulation under the roof, you can reduce cooling and heating costs.
Cost. Galvalume coated steel costs less than stainless steel and roughly the same as galvanized steel. Maintenance and repair needs are minimal, saving you even more money.
Use. Galvalume steel panels can be installed over existing surfaces (like shingles or wood underlayment) or can be installed in an open framing situation. Steel with Galvalume is easily formed, fabricated, bent or stamped without losing the protective coating.
Galvalume also enhances fire resistance! It is also said that Galvalume can last up to 40 years without appreciable change in appearance.
When Should Galvalume® Not Be Used?
Galvalume should not be used in alkaline environments. This is due to the aluminum in Galvalume; it does not hold up well in that type of environment. Galvalume does not do well when damaged. If the panel that is installed will be subject to scratches, cracks, or other immediate damages, then galvanized steel may be a better solution for this application.
Where Can I Purchase Galvalume® Panels?
Mid Florida Metal Roofing Supply has multiple panel options offered in Galvalume coating. From commercial to residential, panels to screws, we have everything you will need for metal roofing job!
Contact us today for a quote! 352-742-7070
About Mid-Florida Metal Roofing
Mid-Florida Metal Roofing Supply has been in the business for 13 years. MFMRS manufactures a wide variety of metal roofing products including Multi-Rib (AG), PBR/R, 5V and Standing Seam in a Galvalume mill finish, as well as, a wide variety of colors to meet all your preferences.
We also manufacture an extensive list of flashing profiles to meet any standard or custom application as needed. We specialize in custom profiles serving a wide variety of needs in the construction industry. Our profiles can also be ordered in custom lengths up to 21ft.
We are committed to producing quality products in a timely manner and pride ourselves with friendly personal customer service.
*Source: Whirlwind Steel https://www.whirlwindsteel.com/blog/bid/264407/what-are-the-benefits-of-galvalume-coatings