Durham's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Durham 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 Durham sits at the 35th percentile for seismic hazard among 4,875 US cities.

How Durham compares

USGS's underlying values for Durham: 0.057g peak ground acceleration, 0.12g at short period, 0.06g at 1 second. Within North Carolina alone, Durham ranks 113 of 147 cities by seismic hazard - the 23th percentile in-state. Durham has a population of about 301,870.

Retrofit economics for Durham

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by North Carolina specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in North Carolina.

Insuring against this, not just retrofitting

A Durham homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where Durham's figures come from

Durham's Category B and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category B does and doesn't tell you about Durham.