Cranston's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Cranston in Seismic Design Category B: Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Rank it against the rest of the country and Cranston sits at the 58th percentile for seismic hazard among 4,875 US cities.

How Cranston compares

The raw figures: peak ground acceleration 0.108g, short-period spectral response 0.196g, 1-second spectral response 0.055g. Among 8 Rhode Island cities in this dataset, Cranston ranks 6 for seismic hazard, the 29th percentile within the state. About 84,448 people live in Cranston, Rhode Island.

What a retrofit costs in Cranston

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

Insuring against this, not just retrofitting

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 Cranston address.

More on how this number was built

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