Does Romeoville, IL need an earthquake retrofit?

Romeoville 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. Nationally, Romeoville ranks above 45% of the 4,875 cities in this dataset for seismic hazard - the 45th percentile.

Where Romeoville sits in Illinois

The raw figures: peak ground acceleration 0.07g, short-period spectral response 0.137g, 1-second spectral response 0.068g. Among 330 Illinois cities in this dataset, Romeoville ranks 92 for seismic hazard, the 72th percentile within the state. About 41,177 people live in Romeoville, Illinois.

What a retrofit costs in Romeoville

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.

Earthquake insurance for a Romeoville 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 Romeoville address.

More on how this number was built

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