Does Seaford, DE need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Seaford is Category A. Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. Rank it against the rest of the country and Seaford sits at the 15th percentile for seismic hazard among 4,875 US cities.

How Seaford compares

The raw figures: peak ground acceleration 0.053g, short-period spectral response 0.107g, 1-second spectral response 0.039g. Among 11 Delaware cities in this dataset, Seaford ranks 9 for seismic hazard, the 20th percentile within the state. About 8,952 people live in Seaford, Delaware.

Bracing and bolting: the actual cost

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

Earthquake insurance for a Seaford home

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 Seaford address.

More on how this number was built

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