Barbara Just had a core ten steel roof put over our garage doors. I was told that you can let it rust to the point you like the color (or you are tired of rust dripping from it) then seal it with exterior polyurethane. But this doesn't have to be done. It will rust to a certain depth then stop. It hasn't rained here so today I wet the roof and then sprayed vinegar on it. Instant rust.

lisavivero I have no experience with that. I would contact manufacturer and get details from them since a metal roof is such a large and visible ticket item, one would hate to make a costly mistake. Good luck.