Does Dunlap, TN need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Dunlap 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. Nationally, Dunlap ranks above 78% of the 4,875 cities in this dataset for seismic hazard - the 78th percentile.

Dunlap by the numbers

USGS's underlying values for Dunlap: 0.229g peak ground acceleration, 0.378g at short period, 0.116g at 1 second. Within Tennessee alone, Dunlap ranks 81 of 104 cities by seismic hazard - the 22th percentile in-state. Dunlap has a population of about 5,960.

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.

Insuring against this, not just retrofitting

A Dunlap 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 Dunlap's figures come from

Dunlap's Category C 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 C does and doesn't tell you about Dunlap.