Madisonville's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Madisonville 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. That puts Madisonville in the 84th percentile nationally for seismic hazard - higher than 84% of the 4,875 US cities USGS was checked against here.

Madisonville by the numbers

The raw figures: peak ground acceleration 0.253g, short-period spectral response 0.468g, 1-second spectral response 0.185g. Among 79 Kentucky cities in this dataset, Madisonville ranks 6 for seismic hazard, the 94th percentile within the state. About 19,502 people live in Madisonville, Kentucky.

Bracing and bolting: the actual cost

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Kentucky. 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 Madisonville address.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced Madisonville'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.