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Comment by tyingq | Hacker News Reader

Steel roofing seems like a fairly upscale thing now, just not with that wavy corrugated shape. The alternating wide flat area, then small rib pattern is the one I see around the most.

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That's called a standing seam metal roof. They're fantastic because the joints are in those raised parts where they stay away from water. The wide flat areas are an unbroken surface that really can't leak. They have an expected life span of 50 years as opposed to 30 for many traditional asphalt shingle roofs and they can be recycled completely. IMHO they're one of the all around best materials. The one reason you don't see more of them is that they cost more up front. But the longer life span means it's really a better long term value.

How do they compare to shale?

Do you mean slate? My perception is they last some 100 years, but now cost $80k to replace.

Slate's expensive, and roofing with it is labour intensive and requires skilled people

Looks lovely but if I was building a house I'd go for a sheet metal roof and it can be done in a couple of days at most even if it won’t be that different cost wise from tiles

> The one reason you don't see more of them is that they cost more up front. But the longer life span means it's really a better long term value.

A really unfortunate truth. Planning for more than 20 years in a house is a rare thing. Home tenure floats around 5-15 years depending on the market. So any investment in a property that doesn't pay off in that time frame is rarely done.

In addition to that, standing seem also allows for solar panels to be clipped onto the seem, removing the need to puncture holes through the roof.

Another advantage is that they reflect heat as well. And for people in fire prone areas, they reduce some of the combustion potential of the roof.

Lots of good reasons in addition to the longevity.

Those will last basically forever. The rib covers the fasteners and prevents water intrusion. The old style corrugated stuff leaks pretty bad unless you torque the screws juuuust right. Pretty sure the grommets under the screw heads degrade after a while, even if you get them perfect.

There's a housing project local to me that installed a bunch of these metal roofs about 20 years ago, and very few are left, they've been replacing them with asphalt shingles. I'm not aware of why, but I presume something went wrong. Certainly the gov't spends as little as it can get away with on those houses, they probably thought it would be cheaper in the long run than asphalt when they did it.

That, or, some politician made a deal with a roofing company to get some perfectly good roofs replaced.

Installing them requires qualified labor. You have to crimp each standing seam just right for the roof to remain watertight. Installing corrugated iron or shingles is much easier in comparison.

It blows my mind that one could screw up corrugated iron roofing. It lasts a long time and is pretty basic to install. Many old villas here in New Zealand have their roofs replaced and they are about 100 years old. Arthur’s Pass down south has houses entirely clad in an every version of the stuff (it’s thick and heavy) and they are over 100 years old now.

> Those will last basically forever.

  Yes, but where? :-) Because those large plates and the attached isolation plates fly damn well when there is a bit of a tempest.

New Zealand. Not the windiest place (Wellington is an exception).

In my local area (US PNW) metal roofs are the opposite of upscale. They were pitched at the low end of the market as being incredibly durable. But they are noisy and ugly, and I only see them installed in lower income neighborhoods. I am also not convinced they've turned out to be as trouble-free as promised, as our local public housing project has started ripping them off and replacing with traditional asphalt shingles.

I agree with you in terms of the reputation of metal roofs - they’re viewed as cheap. But I am not really sure why. The noise isn’t a problem in practice when they’re installed over appropriate decking. Many new roofs also have insulating layers between the highest living spaces and the outside roofing material, which can further reduce the noise. The metal itself can be less attractive, but there are also ones that look more premium and come close to the appearance of other materials. I feel it especially compares well against membranes used on flat roofs (asphalt or various plastic sheets).

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