Tiffin, IA: what USGS's seismic model says

Tiffin 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 Tiffin sits at the 18th percentile for seismic hazard among 4,875 US cities.

How Tiffin compares

USGS's underlying values for Tiffin: 0.035g peak ground acceleration, 0.073g at short period, 0.058g at 1 second. Within Iowa alone, Tiffin ranks 20 of 85 cities by seismic hazard - the 77th percentile in-state. Tiffin has a population of about 6,695.

Bracing and bolting: the actual cost

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 Iowa 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 Iowa.

Insuring against this, not just retrofitting

A Tiffin 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 Tiffin's figures come from

Tiffin'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 Tiffin.