Does Woodridge, IL need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Woodridge 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 Woodridge sits at the 44th percentile for seismic hazard among 4,875 US cities.

How Woodridge compares

The raw figures: peak ground acceleration 0.068g, short-period spectral response 0.133g, 1-second spectral response 0.066g. Among 330 Illinois cities in this dataset, Woodridge ranks 106 for seismic hazard, the 68th percentile within the state. About 34,103 people live in Woodridge, Illinois.

What a retrofit costs in Woodridge

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

More on how this number was built

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