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Comment by anigbrowl | Hacker News Reader

West Coast houses are made not to hurt when they fall on you

True, they're junk. In most places it would be smarter ot make them out of brick, and the chances that they'll fall on the occupant are very low indeed. Some of the oldest (pre 1906) houses in SF are made of brick, ditto in Oakland.

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As it turns out, brick buildings are much more prone to complete collapse than wood houses during earthquakes, owing to the greater flexibility of wood.

Or are you making the argument that that conventional professional wisdom is incorrect?

Unreinforced brick will indeed fall down in even modest earthquakes. In new construction it is possible to sink rebar into the wall, at which point it is at least the equal of concrete (and certainly more attractive); however a lot of people don't want to bother with perceived time and expense and so we go back to concrete and stick framing.

Much construction in California is penny wise and pound foolish. It is routine to omit insulation from the walls in new construction, never mind that it will pay for itself in savings on heating and cooling bills. Wooden houses can be destroyed in an earthquake if the quake shakes them off their foundations; fixing this is simple and easy during construction but, again, wasn't done for a long time. I believe the only reason it is done now is code requirements—it would not overly surprise me to learn that the builders can't be bothered even in new construction.

It's not really the flexibility. Masonry is strong in compression, but heavy, and relatively weak in tensions. It tends to crumble under its own weight.

But yes - brick is good in a hurricane, but a death trap in a quake..

In Europe pretty much any old house is made out of brick. They've been through many earthquakes, built hundreds of years ago and still standing; and this is without reinforcement.

Most earthquakes in Europe aren't all that strong. But when they are:

http://en.wikipedia.org/wiki/1977_Vrancea_earthquake

And the Lisbon earthquake: http://en.wikipedia.org/wiki/1755_Lisbon_earthquake

Probably associated with a new subduction zone that appears to be forming at this side of the Atlantic:

http://www.newscientist.com/article/dn23711-will-new-tectoni...

True, but most of the casualties came from large (poorly built) buildings collapsing, not regular houses.

"In Europe pretty much any old house is made out of brick."

Depends on what is the most easily available building material - here in Scotland pretty much all old buildings are made of stone (everything from small houses up).

NB Speaking of making things from stone - the 5000 year old village of Skara Brae even has remaining furniture made of stone:

http://en.wikipedia.org/wiki/Skara_Brae

Probably wouldn't want to live in one during a strong 6+ earthquake, but they are pretty handy during a hurricane. If you can manage to make the roof stay put.

The reason the pre-1906 buildings are made of brick isn't that brick is superior for surviving earthquakes, but that much construction of the time was brick, and that which wasn't was wood. And most of the destruction of the 1906 quake came from the fire which followed it.

So the only structures which could survive were brick and masonry.

Most of those brick structures have been very significantly reinforced over the years. And if you've ever been next to a brick wall as it's bulging in and out as S waves pass by, you'll likely reconsider your argument.

Steel cage buildings are far preferable to either, from a survivability standpoint.

Even pacific northwest houses? Houses around there in my experience do keep out the bad weather and are far better made than most californian houses.

Oh sorry, I just meant California.

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