The standard is a 55 a z coating underneath the painted metal is a 50 a z coating.
Galvanized vs painted metal roof.
Paint adheres better to galvanized steel than to galvalume so it requires repainting less often.
Aluminum roofing comes with paint finishes as well and have their own warranties.
That coating isn t as dense.
The rust on galvanized will just continue to spread and get worse because it doesn t have that self healing property.
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.
The coating corrodes instead of the core material.
The cost of galvalume and galvalume plus are about the same as that of galvanized steel.
As far as the warranty goes metal roofs hold up great and.
Underneath a painted metal roof there is a galvalume coating.
Final thoughts on galvalume vs.
The metal roofing alliance recommends g 90 galvanized steel for roofing which has 90 ounces of zinc per square foot.
Paint finish warranties are key to understanding the expected longevity of a galvanized or galvalume metal roof.
Technically yes however hot dipped galvanized steel resists corrosion in numerous environments for much longer than uncoated steel.
But galvalume has an excellent performance life in bare exposures as well.
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.
Most galvalume like galvanized steel is coated.
The problem with galvanized metal painted or not is that once it starts to red rust it doesn t eventually stop as galvalume does.
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.
If crawling around on a metal roof in the hot sun does.
Whether it is paint or galvanised steel any coating is designed to protect the base material.
Details about galvanized metal roofing are at galvanized steel roofs.
Both galvanized steel and galvalume weigh 100 to 150 pounds per 100 square feet and contain about 35 recycled materials.
Both types of steel can be painted to improve durability.
With that being said the painted metal roof has a 40 year warranty on the paint and 30 year fade warranty.
That s the normal length of warranty on kynar 500 paint finish.