Does Derby, CT need an earthquake retrofit?

Derby carries Seismic Design Category B under USGS's ASCE 7-16 model. 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 Derby sits at the 59th percentile for seismic hazard among 4,875 US cities.

Where Derby sits in Connecticut

The raw figures: peak ground acceleration 0.113g, short-period spectral response 0.202g, 1-second spectral response 0.054g. Among 21 Connecticut cities in this dataset, Derby ranks 10 for seismic hazard, the 55th percentile within the state. About 12,915 people live in Derby, Connecticut.

Retrofit economics for Derby

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

More on how this number was built

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