Marietta's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Marietta 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 Marietta in the 71th percentile nationally for seismic hazard - higher than 71% of the 4,875 US cities USGS was checked against here.

How Marietta compares

The raw figures: peak ground acceleration 0.112g, short-period spectral response 0.214g, 1-second spectral response 0.09g. Among 148 Georgia cities in this dataset, Marietta ranks 37 for seismic hazard, the 76th percentile within the state. About 63,122 people live in Marietta, Georgia.

Bracing and bolting: the actual cost

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

What this means for insurance

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 Marietta address.

More on how this number was built

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