[paulddraper]

I highly doubt that math makes sense. Especially for an older home.

[shaftway]

I don't. Growing up our house was built in 1910. In '88 we do a retrofit, just in time for the '89 earthquake. Zero damage to the house or anything in it. Friends nearby who didn't retrofit had cracks. They were in the process of figuring out how to handle it when the firestorm of '91 made it moot.

But I'm in new construction. Built in 2015, so I think I'm good on seismics.

[s1artibartfast]

I think it is sound advice.

Insurance quotes rebuilding my older home at 1.1 million due to cost of construction in california. A seismic bolt and brace costs 10k. There is a 70% chance of a M6+ in the next 15 years in my area

[paulddraper]

I was thinking shear walls, steel moment frames, foundation cap and stitch, etc.

You're right that bolt and brace is great.

CA average new construction is $680k. [1]

[1] https://www.costtobuildhouse.com/cost-to-build-a-house-in-ca...

[s1artibartfast]

Yes, and you can double or tripple that $/sqft in sismically active areas like the bay area.