My house has a tin roof over a porch. The house is about one hundred years old, and the tin porch roof is original, as far as I know.
My question is whether the tin roof (which is currently in good shape — no rusting or leaks) will last indefinitely provided that I periodically apply layers of roofing tar to maintain it, or if tin roofs only last so long.
Another way of asking this is: "Is roofing tar a temporary fix for tin roofs that need to be replaced, or will it keep the roof in serviceable shape indefinitely when applied properly?"
When I say "roofing tar," I mean a coating like this, not the "wet patch" temporary fix stuff:
I ask because a contractor is trying to convince me to hire him to replace the tin roof, but it's currently fine and has apparently been there for a long time, so it's not clear why I'd need to rip it out and install a new one.
Best Answer
I guess you mean a galvanized or otherwise coated steel. Life depends on weather, specifically rain. In a desert it will last forever. If the current coating is repaired at any damage spots, it will last almost forever. "Repair" could be anything from dabbing on roofing tar to sandblasting and coating with a zinc-rich epoxy (typically used to protect industrial steel surfaces). Even conventional paints could be used - paint on cars and houses lasts pretty well. It depends on how you want it to look and how often you are willing to "touch it up". For industrial steel tank coatings (aka oil tank farms), touch-up is part of the maintenance program. The contractor is just trying to make money. Addition : There are also "aluminum" coatings commonly sold for mobile home roofs. These may sort of match your galvanized in appearance.