Oak Island, NC: what USGS's seismic model says

Under the seismic model IBC and ASCE 7 use for new construction, Oak Island is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts Oak Island in the 54th percentile nationally for seismic hazard - higher than 54% of the 4,875 US cities USGS was checked against here.

Where Oak Island sits in North Carolina

USGS's underlying values for Oak Island: 0.093g peak ground acceleration, 0.183g at short period, 0.077g at 1 second. Within North Carolina alone, Oak Island ranks 57 of 147 cities by seismic hazard - the 62th percentile in-state. Oak Island has a population of about 9,322.

What a retrofit costs in Oak Island

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 Oak Island 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 Oak Island's figures come from

Oak Island'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 Oak Island.