Does Concord, NC need an earthquake retrofit?

Concord 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 Concord sits at the 54th percentile for seismic hazard among 4,875 US cities.

Concord by the numbers

The raw figures: peak ground acceleration 0.093g, short-period spectral response 0.184g, 1-second spectral response 0.079g. Among 147 North Carolina cities in this dataset, Concord ranks 55 for seismic hazard, the 63th percentile within the state. About 112,395 people live in Concord, North Carolina.

Retrofit economics for Concord

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

More on how this number was built

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