Mount Zion's Seismic Design Category, explained

Mount Zion carries Seismic Design Category C under USGS's ASCE 7-16 model. 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, Mount Zion ranks above 70% of the 4,875 cities in this dataset for seismic hazard - the 70th percentile.

Mount Zion by the numbers

The raw figures: peak ground acceleration 0.1g, short-period spectral response 0.203g, 1-second spectral response 0.103g. Among 330 Illinois cities in this dataset, Mount Zion ranks 54 for seismic hazard, the 84th percentile within the state. About 5,897 people live in Mount Zion, Illinois.

Retrofit economics for Mount Zion

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

Insuring against this, not just retrofitting

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 Mount Zion address.

More on how this number was built

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