Repair rusty corregated metal roof

[Oliver1655]

There are products such as DuroExtend & LoctiteExtend which can be sprayed or brushed over rust, after the scale/loose rust has been removed, which chemically reacts with rust to form a tough, black polymer barrier that locks out future rust. It will then work like a primer & allow you to paint right over it. I'm not sure how pricey it would be in bulk but it does work well. I know several folks who for a quick & easy repair of fender rust used it before applying body filler & several years later the work still looks good.

 

[Creamer]

There are products such as DuroExtend & LoctiteExtend which can be sprayed or brushed over rust, after the scale/loose rust has been removed, which chemically reacts with rust to form a tough, black polymer barrier that locks out future rust. It will then work like a primer & allow you to paint right over it. I'm not sure how pricey it would be in bulk but it does work well. I know several folks who for a quick & easy repair of fender rust used it before applying body filler & several years later the work still looks good.

I agree. Much easier than replacing steel if it is structurally OK it will last as long as new steel.