North Liberty, IA: what USGS's seismic model says

Under the seismic model IBC and ASCE 7 use for new construction, North Liberty is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts North Liberty in the 18th percentile nationally for seismic hazard - higher than 18% of the 4,875 US cities USGS was checked against here.

North Liberty by the numbers

The raw figures: peak ground acceleration 0.035g, short-period spectral response 0.073g, 1-second spectral response 0.058g. Among 85 Iowa cities in this dataset, North Liberty ranks 19 for seismic hazard, the 79th percentile within the state. About 21,904 people live in North Liberty, Iowa.

Bracing and bolting: the actual cost

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

Earthquake insurance for a North Liberty 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 North Liberty address.

More on how this number was built

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