Galvalume Vs Painted Metal Roof

Painting a bare metal roof with white house paint dramatically improves preformance.

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. Aluminum roofing comes with paint finishes as well and have their own warranties. Also see a complete list of types properties of metal used in roof systems for more about galvalume. That coating isn t as dense.

With that being said the painted metal roof has a 40 year warranty on the paint and 30 year fade warranty. Stainless steel roofing system properties. 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. Paint finish warranties are key to understanding the expected longevity of a galvanized or galvalume metal roof. Underneath a painted metal roof there is a galvalume coating. Quick facts about galvalume.

Well first lets address a common misconception. Paint adheres better to galvanized steel than to galvalume so it requires repainting less often. Bare galvanized and painted galvanized perform better in this type of environment. That s the normal length of warranty on kynar 500 paint finish.

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. They have medium relfectivity and poor emissivity 15. I can say from practical experience that nothing beats a white metal roof reflectivity 80 90 and high emissivity 80 90. Bare galvalume and painted galvalume sheets suffer rapid corrosion when in contact with mortar and concrete.

At galvalume metal roofing. Neither galvalume or galvanized substrate is warranted to be used in or around animal confinement or agriculture. The standard is a 55 a z coating underneath the painted metal is a 50 a z coating. There is not a substrate or paint warranty on galvalume products within 1 500 feet of saltwater corrosion resistance when compared to galvanized metal galvalume s corrosion resistance is about two to four times better.

Details about galvalume are.