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Seismic Retrofit and Construction Question


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This is a 3200 sq. ft. California home that the seller claims has undergone extensive renovation to meet all Title 24 provisions and has been "seismically retrofitted". Originally constructed in 1950's and is bolted to the foundation but has typical toenailing at all post / beam joints. Seller provided receipts from contractor for seismic upgrades. Retrofit apparently did not include any brackets or gussets. Four new concrete pads and posts installed but it hardly seems adequate to meet any seismic retrofit upgrades and on engineering plans are available. The four new posts are bracketed to 4x4s that are placed between floor joists and toenailed at each end. Pics provided for detail. So my questions are

- Does it make sense to anyone that an apparently engineered seismic retrofit would not include brackets or gussets at post / beam joints?

- Wouldn't the newer post beam connections only be as strong as the weakest point of the 4x4 toenailed to the floor joists?

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Like you, I am not impressed.

The floor is stronger now, but I see simply four posts added for better support.

The toe-nailed block is crap work, probably due to a poorly located pad. The post in pic 2 has been badly abused with a hammer. It's not easy to work in a crawlspace, but if you're going to embellish it with seismic retro labels, at least spend some time on it and be proud of the result.

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Voluntary seismic upgrades to single-family residences in California do not have to be engineered as long as they do no harm. That translates into no requirement that they do any good either. Regardless, the jurisdictional inspector does not go into the crawlspace.

I think the primary reason that gussets or ties would be good on those post/beam connections is to help resist uplift of the beams. They would have negligible effect on lateral movement, since that aspect is handled by bolting at the perimeter.

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