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I see things like this ("These buildings aren't unsafe because there's no choice, they're unsafe because the builders wanted to save money and the building code

by abduhl 9y ago

I see things like this ("These buildings aren't unsafe because there's no choice, they're unsafe because the builders wanted to save money and the building code was too loose to stop them.") posted by people on HN quite often. As someone who has worked in the Bay Area on buildings, I read things like this and laugh. They come from a place of ignorance - anyone who thinks the building code is "too loose" has never successfully engineered something which complied with it.

bogomipz 9y ago
I don't doubt you but could you elaborate? Thanks.
phkahler 9y ago
>> anyone who thinks the building code is "too loose" has never successfully engineered something which complied with it. Perhaps, but have you compared it to the building code in Japan? I personally have qualifications in this area so I'm just asking.
- phkahler 9y ago
  Too late to edit. Why oh why did I omit the word "don't" in front of "have qualifications"? It was meant to be an honest question to fill a gap, not a weird confrontational thing.
babygoat 9y ago
Your comment would have more gravity if you pointed to specifics instead of touting some vague credentials and telling other people they're wrong.
- JackFr 9y ago
  > more gravity Now that would be a serious problem.
kadenshep 9y ago
Shallow dismissals make you look like you have nothing to say. The article posits one thing, then the OP gave a concrete example clarifying why one region is having problems the other doesn't. You then come in and just claim that the building codes aren't actually that loose while jerking yourself off about your experience in the matter, despite the article's position on unsafe buildings and the OP correctly pointing out that a region with similar problems doesn't have an issue with its high rise buildings that they allowed to be built. Do you have anything else to say besides vague claims on your credentials and experience?
fancyfacebook 9y ago
The fact of the matter is in a best case scenario, 10% of these buildings are going to collapse in a major earthquake. 10% of the newest, shiniest, up to code buildings. Best case, that's the engineering code, that's the spec. They are designed to collapse 10% of the time. In reality many more will collapse, because some buildings are older and not up to code, as well as earthquakes generally just being weird and unpredictable. Do you think 10% of buildings collapsing is a "loose" or "tight" code? 10% losses is acceptable in say, human habitation?
- Retric 9y ago
  That's not how tolerances work. You don't get exactly 10% failure rate, you have to demonstrate better than 10% failure rate which means going past that point. Further, failure is not 'collapse' failure is anyone in the building being unable to exit safely. And again, they are aiming for a 9.0 that's a ridiculously large earthquake. An 7.8 similar to the last SF earthquake would still be a major earthquake, but vastly less dangerous by comparison.
wpietri 9y ago
A code can be both too strict and too loose but for different aspects. The article makes clear that the building code trusts skyscraper developers much more than makers of smaller structures. E.g., "A five-story building has the same strength requirements as a 50-story building." The obvious counterproof to your argument is Millennium Tower, a 60-story skyscraper, which has sank at least 16 inches so far. Most of those one 1 side, so the building now tilts at least 15 inches at the top: https://www.bloomberg.com/news/articles/2017-02-01/who-will-pay-for-san-francisco-s-tilting-sinking-millennium-tower https://www.bloomberg.com/news/articles/2017-02-01/who-will-... They are still trying to figure out how to fix it. Doing so could cost well more than it took to built it in the first place. One proposed plan is to anchor it to bedrock on the low side, then let the tower sink further until it's about even before anchoring the other side: https://sf.curbed.com/2018/4/16/17242450/millennium-tower-sinking-repair-tilting-building-san-francisco https://sf.curbed.com/2018/4/16/17242450/millennium-tower-si... I honestly think it's reasonable that the building code gives skyscrapers a lot of leeway. Traditional building codes are very prescriptive, and that works better with (common and similar) houses than (rare and varied) skyscrapers. But the ongoing clusterfuck that is Millennium Tower makes it clear we can't just trust developers to get it right. As mabbo says, they have a strong financial incentive to cut corners.
- abduhl 9y ago
  Why would the strength requirement for a 5 story building be different from a 50 story building? Do the building materials behave differently when you increase a number? The Millennium Tower is not a "counter proof" to my argument, although it has become a bellwether for exactly the kind of posters I call out in my original post. My argument is that people on here who do armchair structural engineer and make comments like "the building code is too lax" are ignorant and full of shit. All the Millenium Tower proves is that, even with a building code, it is still possible to get unintended consequences. To the rest of your post about skyscrapers getting a lot of leeway - they don't get any more leeway than any other structure, they just have the money it takes to invoke portions of the code that allow alternative analysis methods. It just doesn't make sense financially to do some of the complex modeling for a 3 story building to shave 5% of material costs. If anything, the building code is more stringent on skyscrapers because it does require more advanced analysis. This analysis is NOT precluded for smaller buildings, it is just not worth the money.

by abduhl 9y ago

bogomipz 9y ago

I don't doubt you but could you elaborate? Thanks.

phkahler 9y ago

>> anyone who thinks the building code is "too loose" has never successfully engineered something which complied with it. Perhaps, but have you compared it to the building code in Japan? I personally have qualifications in this area so I'm just asking.

phkahler 9y ago
Too late to edit. Why oh why did I omit the word "don't" in front of "have qualifications"? It was meant to be an honest question to fill a gap, not a weird confrontational thing.

babygoat 9y ago

Your comment would have more gravity if you pointed to specifics instead of touting some vague credentials and telling other people they're wrong.

JackFr 9y ago
> more gravity Now that would be a serious problem.

kadenshep 9y ago

Shallow dismissals make you look like you have nothing to say. The article posits one thing, then the OP gave a concrete example clarifying why one region is having problems the other doesn't. You then come in and just claim that the building codes aren't actually that loose while jerking yourself off about your experience in the matter, despite the article's position on unsafe buildings and the OP correctly pointing out that a region with similar problems doesn't have an issue with its high rise buildings that they allowed to be built. Do you have anything else to say besides vague claims on your credentials and experience?

fancyfacebook 9y ago

The fact of the matter is in a best case scenario, 10% of these buildings are going to collapse in a major earthquake. 10% of the newest, shiniest, up to code buildings. Best case, that's the engineering code, that's the spec. They are designed to collapse 10% of the time. In reality many more will collapse, because some buildings are older and not up to code, as well as earthquakes generally just being weird and unpredictable. Do you think 10% of buildings collapsing is a "loose" or "tight" code? 10% losses is acceptable in say, human habitation?

Retric 9y ago
That's not how tolerances work. You don't get exactly 10% failure rate, you have to demonstrate better than 10% failure rate which means going past that point. Further, failure is not 'collapse' failure is anyone in the building being unable to exit safely. And again, they are aiming for a 9.0 that's a ridiculously large earthquake. An 7.8 similar to the last SF earthquake would still be a major earthquake, but vastly less dangerous by comparison.

wpietri 9y ago

A code can be both too strict and too loose but for different aspects. The article makes clear that the building code trusts skyscraper developers much more than makers of smaller structures. E.g., "A five-story building has the same strength requirements as a 50-story building." The obvious counterproof to your argument is Millennium Tower, a 60-story skyscraper, which has sank at least 16 inches so far. Most of those one 1 side, so the building now tilts at least 15 inches at the top: https://www.bloomberg.com/news/articles/2017-02-01/who-will-pay-for-san-francisco-s-tilting-sinking-millennium-tower https://www.bloomberg.com/news/articles/2017-02-01/who-will-... They are still trying to figure out how to fix it. Doing so could cost well more than it took to built it in the first place. One proposed plan is to anchor it to bedrock on the low side, then let the tower sink further until it's about even before anchoring the other side: https://sf.curbed.com/2018/4/16/17242450/millennium-tower-sinking-repair-tilting-building-san-francisco https://sf.curbed.com/2018/4/16/17242450/millennium-tower-si... I honestly think it's reasonable that the building code gives skyscrapers a lot of leeway. Traditional building codes are very prescriptive, and that works better with (common and similar) houses than (rare and varied) skyscrapers. But the ongoing clusterfuck that is Millennium Tower makes it clear we can't just trust developers to get it right. As mabbo says, they have a strong financial incentive to cut corners.

abduhl 9y ago
Why would the strength requirement for a 5 story building be different from a 50 story building? Do the building materials behave differently when you increase a number? The Millennium Tower is not a "counter proof" to my argument, although it has become a bellwether for exactly the kind of posters I call out in my original post. My argument is that people on here who do armchair structural engineer and make comments like "the building code is too lax" are ignorant and full of shit. All the Millenium Tower proves is that, even with a building code, it is still possible to get unintended consequences. To the rest of your post about skyscrapers getting a lot of leeway - they don't get any more leeway than any other structure, they just have the money it takes to invoke portions of the code that allow alternative analysis methods. It just doesn't make sense financially to do some of the complex modeling for a 3 story building to shave 5% of material costs. If anything, the building code is more stringent on skyscrapers because it does require more advanced analysis. This analysis is NOT precluded for smaller buildings, it is just not worth the money.