Fort Collins's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Fort Collins is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Nationally, Fort Collins ranks above 57% of the 4,875 cities in this dataset for seismic hazard - the 57th percentile.

Fort Collins by the numbers

USGS's underlying values for Fort Collins: 0.102g peak ground acceleration, 0.191g at short period, 0.056g at 1 second. Within Colorado alone, Fort Collins ranks 51 of 79 cities by seismic hazard - the 36th percentile in-state. Fort Collins has a population of about 170,924.

What a retrofit costs in Fort Collins

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 Colorado 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 Colorado.

Insuring against this, not just retrofitting

A Fort Collins 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 Fort Collins's figures come from

Fort Collins'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 Fort Collins.