Silverthorne's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Silverthorne in Seismic Design Category C: Moderate seismic hazard. Code adds irregular-building restrictions and requires bracing of some nonstructural components (e.g. tall shelving, water heaters) in addition to structural detailing. Rank it against the rest of the country and Silverthorne sits at the 77th percentile for seismic hazard among 4,875 US cities.

Where Silverthorne sits in Colorado

The raw figures: peak ground acceleration 0.192g, short-period spectral response 0.348g, 1-second spectral response 0.09g. Among 79 Colorado cities in this dataset, Silverthorne ranks 10 for seismic hazard, the 88th percentile within the state. About 5,220 people live in Silverthorne, Colorado.

Retrofit economics for Silverthorne

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Colorado. A typical retrofit still runs $5,000-$10,000 nationally, about $7,000 for a common single-family job.

Earthquake insurance for a Silverthorne 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 Silverthorne address.

More on how this number was built

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