Montgomery's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Montgomery is 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 Montgomery sits at the 48th percentile for seismic hazard among 4,875 US cities.

Montgomery by the numbers

USGS's underlying values for Montgomery: 0.073g peak ground acceleration, 0.141g at short period, 0.067g at 1 second. Within Illinois alone, Montgomery ranks 75 of 330 cities by seismic hazard - the 78th percentile in-state. Montgomery has a population of about 21,957.

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 Montgomery home

A Montgomery 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 Montgomery's figures come from

Montgomery'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 Montgomery.