Does Glen Ellyn, IL need an earthquake retrofit?
Glen Ellyn 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. That puts Glen Ellyn in the 42th percentile nationally for seismic hazard - higher than 42% of the 4,875 US cities USGS was checked against here.
Where Glen Ellyn sits in Illinois
USGS's underlying values for Glen Ellyn: 0.066g peak ground acceleration, 0.129g at short period, 0.065g at 1 second. Within Illinois alone, Glen Ellyn ranks 124 of 330 cities by seismic hazard - the 63th percentile in-state. Glen Ellyn has a population of about 28,872.
Retrofit economics for Glen Ellyn
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.
Insuring against this, not just retrofitting
A Glen Ellyn 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 Glen Ellyn's figures come from
Glen Ellyn'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 Glen Ellyn.