59 comments

[ 3.4 ms ] story [ 166 ms ] thread
Thanks, you reminded me to donate to the indispensable free things we take for granted.

https://archive.org/donate/

Should be publicly funded tbh
I agree, but it should also be immutable, and only the former with the latter. Especially with the political scrubbing of past news articles.
(comment deleted)
Although I do agree with the mission of archiving content, I find it quite interesting to be willing to pay for an organisation to archive content as a way to get content for free rather than pay for the content itself.

It's a bit of a conundrum because we need both, so ideally everyone would pay for both. It costs money to archive content, it also costs money to produce it.

Now this is under the assumption you're praising archiving services as a workaround paywalls, but I may have misinterpreted your comment: in which case feel free to correct me!

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.
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).
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.

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).
(comment deleted)
When I built a turkey coop this past spring, plywood price was at its peak, so I decided I'd side and roof it with 18-gauge steel. It was quick, easy, looks great, and has proven itself weather-tight. I love working with wood, but I have to say the ease, cost, and looks of the steel have converted me for this purpose.

Also,

> More intuitively, consider a common pizza-eating strategy: gently bending your slice before bringing it to your mouth obviates the risk of buckling and consequent mess.

is a perfect, natural analogy. Why can I never come up with such beautiful explanations?

IMO good analogies come from a place of empathy. An understanding that the people you are talking to are not dumb, just uninitiated.

Not sure how applicable that observation is. Just sharing a thought.

> is a perfect, natural analogy. Why can I never come up with such beautiful explanations?

Good writers borrow: great writers steal.

It would be nice to come up with the right analogy from whole cloth, but especially in non-fiction writing it's almost as good to recognize a great analogy or turn of phrase, store it away in your mind, and reproduce it (rewritten in the house style, perhaps) when you need the mot juste for your own readers. I've heard the analogy before, and I suspect the writer or editor of the Economist had too.

I can't access the article, so out of curiosity, why isn't rust a problem?
Despite the name, it's usually steel, not iron. And a newer galvanization process that's a mixture of aluminum and zinc.
Steel does rust, but good metallurgy and coatings help. I live in the upper Midwest where road salt is used quite heavily, yet the prevalence of super rusty cars has really diminished.

Steel items that are not exposed to salt either rust much more slowly, or develop a patina that slows further rusting. That's not quite so easy in coastal areas.

Modern stuff is treated. Old stuff like a roof I had was just thicker than modern. The roof was standing seams at probably 30-40 years old. While there was rust, it was superficial. Takes a long time rust clear through even in Florida.
In my area, corrugated steel is sold with 'zinc-alum' and powder-coating pre-applied.

I think they also apply paint to cut edges and drilled holes during installation.

Its extremely popular, probably seen on around 50% of roofs, and is also used for exterior cladding on a lot of new houses.

(although as cladding, it's usually used for only half the house, alternating with some other cladding)

It's galvanised. These days you can also get pre-finished corrugated iron (Colorbond), which also has a layer of polyester paint baked on.
most under utilized building material
The article claims that some aircraft have been made with corrugated iron or steel:

>aircraft hangars, aircraft themselves

But I doubt that. (Corrugated aluminum, sure.)

The Junkers J1 was made from steel, some corrugated, some not, so it is just possible to make one fly. It was a real pig in the air, by all accounts.
Thanks. The Wikipedia page says that only one J1 was built.
I often wonder why these aren’t the material of choice for interior uses as well. Why does everything use drywall, which requires the messiness of mudding and taping and so on? I feel like a metal panel system that is removable would be much more durable and would allow access to the in-between spaces more easily.
Metal makes for unpleasant acoustics.

Probably you could spray some kind of sound-absorbent layer over it, but then you'd be back to messiness again.

For starters, metal interior panels seems like a great way to get electrocuted.
Screwed on ply sheets look better, perform better and meet your requirements I think?
I've seen aluminium panelling used in interiors (in commercial buildings) which works. Steel I think would mostly be too heavy for interior cladding.
I live in rural Australia. Corrugated iron is everywhere, and I love it. It is durable, lasts a really long time, is easy to repurpose. I know an older gentleman here who built a really nice barn out of some repurposed corrugated iron roofing. I'm about to build a shed for a home office, and will use corrugated iron. It is cheap, easy to work with, comes in decent colors (e.g. the ColorBond brand in Australia), is strong without being overengineered. It's great stuff.
I grew up in rural Australia (now a long way from there) and one of my memory triggers is the sound of old corrugated iron ‘ticking’ and ‘pinging’ after a day in the hot sun.
Yeah, that and the lovely tap-tap-tap of the rain on a tin roof
There's even a song about it. :)

(OK maybe more than just one...)

I’m a New Zealander and laughed at this - of course the Australian remembers what it does with heat. Over here it’s massive rainfall, not heat, which generates the noise.
Agreed. Colourbond on our house and shed, and most in the street. Next door's 40yo corrugated shed roof is a work of rust orange beauty. The sounds on a hot day too ... unmistakable and so of the place :)
As a NZer, I say about time you all caught up.
Perhaps the most unorthodox use of corrugated iron was the Bob Semple tank [1] of WWII. It was basically a corrugated iron shell on a Caterpillar D8 chassis, with 6 machine guns for armament. The eponymous designer and New Zealand's Minister for Works at the time, Bob Semple, based his design off a photo of an American tank he had on a postcard.

Needless to say, it wasn't exactly successful. Only 3 prototypes were built, none were used in combat, and they were eventually converted back into tractors.

[1] https://en.wikipedia.org/wiki/Bob_Semple_tank