Terre Haute's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Terre Haute 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. Nationally, Terre Haute ranks above 74% of the 4,875 cities in this dataset for seismic hazard - the 74th percentile.

Where Terre Haute sits in Indiana

The raw figures: peak ground acceleration 0.139g, short-period spectral response 0.273g, 1-second spectral response 0.114g. Among 126 Indiana cities in this dataset, Terre Haute ranks 11 for seismic hazard, the 92th percentile within the state. About 58,531 people live in Terre Haute, Indiana.

What a retrofit costs in Terre Haute

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

Earthquake insurance for a Terre Haute 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 Terre Haute address.

More on how this number was built

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