6 ms·

I don't know what the underlying geography of SF is like, but in case you have ever wondered why Manhattan is only vertically developed in two areas of the isla

I don't know what the underlying geography of SF is like, but in case you have ever wondered why Manhattan is only vertically developed in two areas of the island where there are tall skylines (with a lot of low-lying areas in between, i.e. the Village, Chelsea, Chinatown, Little Italy, etc), it is because those are the only two areas on the island where the bedrock can support that type of development. I don't know if this factors into SF development options, but just an FYI.

pstrateman 11y ago
There are a bunch of very tall buildings in SF built on landfill. The issue is entirely politics not engineering.
dantheman 11y ago
That's historical and enforced by zoning. Large buildings can now be built anywhere.
coderzach 11y ago
http://observer.com/2012/01/uncanny-valley-the-real-reason-there-are-no-skyscrapers-in-the-middle-of-manhattan/ http://observer.com/2012/01/uncanny-valley-the-real-reason-t...
- hellofunk 11y ago
  This is rather interesting. I took a course many years ago at NYU on the history of the city, and my parent comment was taught to us in the class by none other than the Dean of the actual school. Fascinating.
  - potatolicious 11y ago
    It's an incredibly common urban legend even in the city itself - fortunately with no basis in reality. As an example the Metropolitan Life North Building right next to Madison Square Park was originally designed in the 20s to beat the Empire State for height (but sadly, the Depression happened), and that plot of land is firmly on the "soft" ground "unsuitable" for tall skyscrapers. Not only do we not need the bedrock now, it appears we never needed it - and the engineers of the early 20th century knew this as well as we do.
    - HillaryBriss 11y ago
      Yes. And any tall building in SF's Embarcadero stands in defiance of the need for bedrock. A lot of the land there is just old, accidental landfill. Also, I think, but, I'm not sure, that they built this extremely large, heavy structure right over the bay itself a few years back, something about helping cars get from Oakland to SF and back. I don't know how much bedrock they found underneath the supports for that thing, whatever it's called. Can't seem to remember its name ...
rhino369 11y ago
Bedrock is not needed to build a sky scraper. It was just natural trends, not enforced with zoning laws.
- avn2109 11y ago
  >> "Bedrock is not needed to build a sky scraper..." True, but that's because of comparatively recent developments in geotechnical engineering. They needed it during the first wave of skyscraper development.
  - rhino369 11y ago
    The first NYC ones certainly used bedrock. But floating raft system was invented in Chicago in 1882. So I wouldn't say recent.
raldi 11y ago
They're building the new Transbay Tower in SF on soft ground. It just means they had to put in a bunch of very deep piles and a foundation that constituted one of the largest concrete pours of all time. But the real estate market is such that they were happy to do it, in exchange for permission to build the tallest building in the city.
deleted 11y ago
[deleted]

pstrateman 11y ago

There are a bunch of very tall buildings in SF built on landfill. The issue is entirely politics not engineering.

dantheman 11y ago

That's historical and enforced by zoning. Large buildings can now be built anywhere.

coderzach 11y ago

http://observer.com/2012/01/uncanny-valley-the-real-reason-there-are-no-skyscrapers-in-the-middle-of-manhattan/ http://observer.com/2012/01/uncanny-valley-the-real-reason-t...

hellofunk 11y ago
This is rather interesting. I took a course many years ago at NYU on the history of the city, and my parent comment was taught to us in the class by none other than the Dean of the actual school. Fascinating.
- potatolicious 11y ago
  It's an incredibly common urban legend even in the city itself - fortunately with no basis in reality. As an example the Metropolitan Life North Building right next to Madison Square Park was originally designed in the 20s to beat the Empire State for height (but sadly, the Depression happened), and that plot of land is firmly on the "soft" ground "unsuitable" for tall skyscrapers. Not only do we not need the bedrock now, it appears we never needed it - and the engineers of the early 20th century knew this as well as we do.
  - HillaryBriss 11y ago
    Yes. And any tall building in SF's Embarcadero stands in defiance of the need for bedrock. A lot of the land there is just old, accidental landfill. Also, I think, but, I'm not sure, that they built this extremely large, heavy structure right over the bay itself a few years back, something about helping cars get from Oakland to SF and back. I don't know how much bedrock they found underneath the supports for that thing, whatever it's called. Can't seem to remember its name ...

rhino369 11y ago

Bedrock is not needed to build a sky scraper. It was just natural trends, not enforced with zoning laws.

avn2109 11y ago
>> "Bedrock is not needed to build a sky scraper..." True, but that's because of comparatively recent developments in geotechnical engineering. They needed it during the first wave of skyscraper development.
- rhino369 11y ago
  The first NYC ones certainly used bedrock. But floating raft system was invented in Chicago in 1882. So I wouldn't say recent.

raldi 11y ago

They're building the new Transbay Tower in SF on soft ground. It just means they had to put in a bunch of very deep piles and a foundation that constituted one of the largest concrete pours of all time. But the real estate market is such that they were happy to do it, in exchange for permission to build the tallest building in the city.

deleted 11y ago

[deleted]