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Comment by ClumsyPilot | Hacker News Reader

Most houses last basically forever with "proper care", the question is how difficult/likely is 'proper care'

Regular reminder that stainless steel reinforcement exists, is used bridges and it's use outside is growing, and it will last a thousand years.

Also there is Basalt, carbon fiber and even reinforcement out of used wind turbine blades, which is used in Britain for HS2, and other non-steel reinforcements, which can give you a structure nearly impervious to weathering.

On wood: In Europe we've been using Mass Timber for decides, and it's really good from Carbon perspective and outperforms RCC for small to medium residential and office buildings. Probably not going to replace RCC in infrastructure and industry, but what do I know

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Stainless reinforcement is definitely not guaranteed to last 1000 years. Most grades of stainless are susceptible to stress corrosion cracking in any environment containing chlorides (even at relatively low levels), which is pretty much any bridge, industrial, or habitated structure - everything from road salt, to bleach, to chlorinated tap water can be a problem over a long enough period of time.

This has been a big issue with stainless steel climbing anchors and hangars, as it leads to sudden catastrophic failure with little warning, as you don’t get rust like normal steel. Some areas near the ocean have had failures in as little as 5 years - faster than if they’d used normal steel.

Regarding climbing anchors: Anybody expecting to use steel near the ocean and having it last, is in for a really bad time. Ti glue-ins are really the best way to go near water. Plus, I'm sure you're aware of how many variables there are.

Even 316 rusts and corrodes, and that should be fairly obvious to most users if they actually look at the bolts before trusting them.

Agreed, what got people for awhile is that while there is sometimes visible rust - sometimes there isn’t - and even then nothing like normal steel or iron. Then it fails. Or doesn’t.

Not what you want in rebar (or climbing anchors!)

It's shocking just how much seawater will corrode steel. If you look at pictures of shipwrecks like the Lusitania and Titanic they've degraded a lot since they were first dived to in the '60s and '80s respectively. The former barely even resembles a ship now.

Modern bridges made from concrete are not designed to last more than a century. I believe the expected usefulness of something like a cable stayed bridge is around 100 years. Compare that to a suspension bridge which can be used almost indefinitely.

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