Oh, another disadvantage with metal roofs - they block satellite reception inside the house remarkably well. Neither my phone’s GPS or my handheld GPS unit will acquire satellites in the house. I got a femtocell, and had to put the GPS antenna outside to make it work. I suspect satellite radio wouldn’t work in the house.
tin could also be used for thin steel sheeting that might be tin plated, painted or galvanized. i think that usage is widespread so that the scrap/recycling industry refers to any thin steel sheeting, likely coated, as tin to classify it.
As mentioned above, one of the most common roofing materials here in Australia is galvanised steel sheet. Modern sheeting has a near indefinite life. Steel sheet is coated with a “galvanic” layer, originally zinc, now a mixture of zinc and aluminium. This layer prevents corrosion of any steel reasonably close to the coating, so cut edges and drilled holes won’t rust. Cutting must be done with a cutter that won’t burn the coating, so abrasive cutters can’t be used. This goes by the name “Zincalum” (Pronounced zinc aloom") A common addition is a factory applied coloured layer, with the proprietory name “Colourbond”
In coastal areas where salt is a problem, they do suggest that stainless steel is used. SS is a pain in many ways. It is more expensive, and it is really horrid to work with.
My house has a flat zincalum coated steel roof. It does have many advantages. It is very weatherproof, has good thermal properties (I have naked coatings, and the silver metal colour has a very low emissivity.) I can walk on the roof, although the newer sheets are thinner than those of old and will dent slightly.
I had Colorbond (note the spelling) on a pitched roof. Zincalum seems to be pretty rare in these parts, at least for pitched roofs. And yeah, it’s good stuff. Developers seem to charge a premium for it even though I think it’s cheaper to build than a tiled roof, presumably because it’s in demand.
I’m surprised to see the American steel roofs are designed to imitate shingles. For comparison here’s what the Aussie stuff looks like.
There is a wide variety of steel roofing available now. I think the most common is plain old ribbed roofing, ribs at both edges of a 24’’ wide piece and one or more others. I have seen steel roofing that looks like tile, shingles, and maybe other stuff. Unless you see it being installed, there is no telling how much of that stuff is around.
We had a hail storm here late last year. Of all the new roofs, I think I have only seen one that wasn’t plain old shingles. Unfortunately, our 15 year old shingles weren’t damaged and we aren’t getting a new roof at out insurance company’s expense.
My Grandfather had an aluminum roof on his farmhouse. It was pretty old when I was visiting more than thirty years ago, and as far as I know it is still in fine shape today. I’ll ask my cousin, who has been down there fairly recently and visited the new owners.
Never leaked, and the aluminum reflected the sun away keeping the house cooler. Good system.