Does Royal Oak, MI need an earthquake retrofit?

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Royal Oak in Seismic Design Category B: Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Nationally, Royal Oak ranks above 28% of the 4,875 cities in this dataset for seismic hazard - the 28th percentile.

How Royal Oak compares

The raw figures: peak ground acceleration 0.047g, short-period spectral response 0.095g, 1-second spectral response 0.045g. Among 153 Michigan cities in this dataset, Royal Oak ranks 73 for seismic hazard, the 53th percentile within the state. About 58,251 people live in Royal Oak, Michigan.

Bracing and bolting: the actual cost

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

Earthquake insurance for a Royal Oak 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 Royal Oak address.

More on how this number was built

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