Does San Luis, AZ need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places San Luis in Seismic Design Category D: High seismic hazard - this is the category most of coastal California, the Pacific Northwest, and other active fault regions fall into. Code mandates significant seismic detailing and restricts irregular structural configurations. This is the category the Brace + Bolt scope (cripple-wall bracing, foundation bolting) is built for. Nationally, San Luis ranks above 84% of the 4,875 cities in this dataset for seismic hazard - the 84th percentile.

How San Luis compares

The raw figures: peak ground acceleration 0.279g, short-period spectral response 0.666g, 1-second spectral response 0.279g. Among 57 Arizona cities in this dataset, San Luis ranks 1 for seismic hazard, the 100th percentile within the state. About 40,064 people live in San Luis, Arizona.

Bracing and bolting: the actual cost

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Arizona. A typical retrofit still runs $5,000-$10,000 nationally, about $7,000 for a common single-family job.

What this means for insurance

Outside California, earthquake coverage is typically sold as an endorsement added to a standard homeowners policy, not a separate product - worth asking about directly when getting a home-insurance quote for a San Luis address.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced San Luis's numbers. The guide to what a Seismic Design Category actually means covers why a category is never a substitute for an engineer's assessment of one specific house.