Does Portage, IN need an earthquake retrofit?

Under the seismic model IBC and ASCE 7 use for new construction, Portage is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Nationally, Portage ranks above 32% of the 4,875 cities in this dataset for seismic hazard - the 32th percentile.

Portage by the numbers

The raw figures: peak ground acceleration 0.054g, short-period spectral response 0.111g, 1-second spectral response 0.065g. Among 126 Indiana cities in this dataset, Portage ranks 118 for seismic hazard, the 6th percentile within the state. About 38,576 people live in Portage, Indiana.

Retrofit economics for Portage

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.

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 Portage address.

More on how this number was built

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