Does Sandwich, IL need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Sandwich 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 Sandwich sits at the 49th percentile for seismic hazard among 4,875 US cities.

Where Sandwich sits in Illinois

USGS's underlying values for Sandwich: 0.076g peak ground acceleration, 0.145g at short period, 0.069g at 1 second. Within Illinois alone, Sandwich ranks 69 of 330 cities by seismic hazard - the 79th percentile in-state. Sandwich has a population of about 7,299.

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 Illinois 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 Illinois.

Earthquake insurance for a Sandwich home

A Sandwich 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 Sandwich's figures come from

Sandwich'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 Sandwich.