I live near the Cascadia Subduction Zone, which you may know is one of the only places in the U.S. expected to have an earthquake and tsunami similar to the one in Japan. And I'm currently shopping for houses...(out of the flood zone, at least).
I found a 1900 craftsman-style bungalow I like that seems to have a few things in its favor, quake-wise, as compared to most houses in this style. It has no unreinforced masonry (no stone columns on the porch, and no chimney - just a woodstove). It is all wood construction, which is supposed to be safer in quakes than brick or concrete. But it is on wooden posts and piers for the foundation, and like most older houses here they are too far apart for comfort.
I found something inexpensive called "Anchorpanel" retrofitting, a somewhat local company (northern California), and I'm wondering if anyone has experience with or opinions about their process. Here's a short description from their website: "Cast-in-place panels provide superior seismic strength (for a lot less money). Existing structures don't have to be raised or lowered. Simply attach the panels and pump concrete in the trench. UBC and IBC/IRC conformance."
My concern is with the concrete part - wouldn't this put added stress on the house in the event of an earthquake? Is it better to have some sort of metal bracing instead, while allowing the house to "roll with the quake?" I've read in various places that posts & piers can survive better in an earthquake because they don't make the house absorb the full shock.
Does anyone else have experience with affordable retro-fitting of old post/pier houses? (Gotta save some money for the inevitable repairs *after* a quake, since there's really no way to "earthquake-proof.")
I found a 1900 craftsman-style bungalow I like that seems to have a few things in its favor, quake-wise, as compared to most houses in this style. It has no unreinforced masonry (no stone columns on the porch, and no chimney - just a woodstove). It is all wood construction, which is supposed to be safer in quakes than brick or concrete. But it is on wooden posts and piers for the foundation, and like most older houses here they are too far apart for comfort.
I found something inexpensive called "Anchorpanel" retrofitting, a somewhat local company (northern California), and I'm wondering if anyone has experience with or opinions about their process. Here's a short description from their website: "Cast-in-place panels provide superior seismic strength (for a lot less money). Existing structures don't have to be raised or lowered. Simply attach the panels and pump concrete in the trench. UBC and IBC/IRC conformance."
My concern is with the concrete part - wouldn't this put added stress on the house in the event of an earthquake? Is it better to have some sort of metal bracing instead, while allowing the house to "roll with the quake?" I've read in various places that posts & piers can survive better in an earthquake because they don't make the house absorb the full shock.
Does anyone else have experience with affordable retro-fitting of old post/pier houses? (Gotta save some money for the inevitable repairs *after* a quake, since there's really no way to "earthquake-proof.")