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There is a practical aspect to building height. Berkeley is on an earthquake fault line, and buildings in the 6-15 storey range have a natural resonance that t

There is a practical aspect to building height. Berkeley is on an earthquake fault line, and buildings in the 6-15 storey range have a natural resonance that tends to match the frequency of earthquake waves. I'm having difficulty finding references to this, so maybe it's not as big a deal as I thought? http://www.bgs.ac.uk/discoveringGeology/hazards/earthquakes/howAffectBuildings.html http://www.bgs.ac.uk/discoveringGeology/hazards/earthquakes/...

NickNameNick 8y ago
That was certainly our experience here. "Wellington's mid-rise buildings worst affected by earthquake" https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11750524 https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&object... NB, the defence headquarters building, and the statistics building mentioned in the article have since been demolished.
mc32 8y ago
That's not a real excuse. Tokyo is crisscrossed with fault-lines and they manage to build to quake code --the proof being all the healthy buildings despite frequent quakes. Berkeley is just putting up excuses.
rohit2412 8y ago
I thought buildings can be reinforced. How does Tokyo manage it's buildings?
ThrustVectoring 8y ago
The breakpoints have more to do with other parts of building codes. Wood framing is only strong enough to support three floors (unless you use cross laminated timber, which is a relatively new construction technology). Furthermore there are increasing requirements for fire suppression and accessibility as you add height. The breakpoints are basically either 2-floor duplex through quadplex that don't need elevators, or putting three floors of wood-framed apartments over a concrete or steel podium that contains commercial space and parking. Podium construction basically explains why so many 4 and 5 floor buildings get put up - it's significantly cheaper than the more expensive material required to make stuff strong enough for taller buildings.
- erik_seaberg 8y ago
  Isn't the land a lot of the cost? Why isn't it worthwhile to spend 3x on construction and collect from 2x as many occupants?
  - ThrustVectoring 8y ago
    Depends on the location. In the Bay Area a large portion of the cost is having your capital tied up for like 5+ years while trying to get your project approved.

NickNameNick 8y ago

That was certainly our experience here. "Wellington's mid-rise buildings worst affected by earthquake" https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11750524 https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&object... NB, the defence headquarters building, and the statistics building mentioned in the article have since been demolished.

mc32 8y ago

That's not a real excuse. Tokyo is crisscrossed with fault-lines and they manage to build to quake code --the proof being all the healthy buildings despite frequent quakes. Berkeley is just putting up excuses.

rohit2412 8y ago

I thought buildings can be reinforced. How does Tokyo manage it's buildings?

ThrustVectoring 8y ago

The breakpoints have more to do with other parts of building codes. Wood framing is only strong enough to support three floors (unless you use cross laminated timber, which is a relatively new construction technology). Furthermore there are increasing requirements for fire suppression and accessibility as you add height. The breakpoints are basically either 2-floor duplex through quadplex that don't need elevators, or putting three floors of wood-framed apartments over a concrete or steel podium that contains commercial space and parking. Podium construction basically explains why so many 4 and 5 floor buildings get put up - it's significantly cheaper than the more expensive material required to make stuff strong enough for taller buildings.

erik_seaberg 8y ago
Isn't the land a lot of the cost? Why isn't it worthwhile to spend 3x on construction and collect from 2x as many occupants?
- ThrustVectoring 8y ago
  Depends on the location. In the Bay Area a large portion of the cost is having your capital tied up for like 5+ years while trying to get your project approved.