Does Cullman, AL need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Cullman is 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. That puts Cullman in the 73th percentile nationally for seismic hazard - higher than 73% of the 4,875 US cities USGS was checked against here.

Cullman by the numbers

The raw figures: peak ground acceleration 0.136g, short-period spectral response 0.258g, 1-second spectral response 0.11g. Among 107 Alabama cities in this dataset, Cullman ranks 53 for seismic hazard, the 51th percentile within the state. About 20,239 people live in Cullman, Alabama.

Retrofit economics for Cullman

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

Earthquake insurance for a Cullman 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 Cullman address.

More on how this number was built

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