Galvalume Vs Painted Metal Roof

Stainless steel is generally a rust resistant material but it s corrosion resistance to salt depends on the stainless steel alloy or grade.

Galvalume vs painted metal roof. Bare galvanized and painted galvanized perform better in this type of environment. Galvalume s formula was designed to combine the toughness and strength of zinc with the rust resistance of aluminum. They have medium relfectivity and poor emissivity 15. Stainless steel roofing system properties.

The standard is a 55 a z coating underneath the painted metal is a 50 a z coating. That coating isn t as dense. All things being equal standing seam metal roof will cost more than metal shingles although performance wise they offer pretty much the same benefits and longevity. Well first lets address a common misconception.

Additionally primer and paint adhere better to galvalume coated panels and they carry a 20 year limited warranty while galvanized panels do not making them a smarter long term investment for your customers homes agricultural buildings or commercial properties. Underneath a painted metal roof there is a galvalume coating. At galvalume metal roofing. Bare galvalume and painted galvalume sheets suffer rapid corrosion when in contact with mortar and concrete.

Neither galvalume or galvanized substrate is warranted to be used in or around animal confinement or agriculture. That s the normal length of warranty on kynar 500 paint finish. Paint adheres better to galvanized steel than to galvalume so it requires repainting less often. I can say from practical experience that nothing beats a white metal roof reflectivity 80 90 and high emissivity 80 90.

With kynar 500 or hylar 5000 paint finish or its equivalent you will not have to paint over your steel roof for at least 30 years. Galvanized and galvalume metal roofs are hot roofs. The big difference is that aluminum will oxidize chalk if exposed to the elements but the aluminum will not look unsightly and continue on with a rapid oxidation process deterioration rust as steel will. If you must go with steel make sure its galvalume or at the very least galvanized steel in case of steel shingles.

Details about galvalume are. Also see a complete list of types properties of metal used in roof systems for more about galvalume. Aluminum roofing comes with paint finishes as well and have their own warranties. Quick facts about galvalume.

With that being said the painted metal roof has a 40 year warranty on the paint and 30 year fade warranty.