Knoxville's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Knoxville in Seismic Design Category D: High seismic hazard - this is the category most of coastal California, the Pacific Northwest, and other active fault regions fall into. Code mandates significant seismic detailing and restricts irregular structural configurations. This is the category the Brace + Bolt scope (cripple-wall bracing, foundation bolting) is built for. That puts Knoxville in the 88th percentile nationally for seismic hazard - higher than 88% of the 4,875 US cities USGS was checked against here.

Knoxville by the numbers

USGS's underlying values for Knoxville: 0.42g peak ground acceleration, 0.619g at short period, 0.133g at 1 second. Within Tennessee alone, Knoxville ranks 28 of 104 cities by seismic hazard - the 74th percentile in-state. Knoxville has a population of about 198,722.

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 Tennessee 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 Tennessee.

What this means for insurance

A Knoxville 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 Knoxville's figures come from

Knoxville's Category D 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 D does and doesn't tell you about Knoxville.