Cambridge's Seismic Design Category, explained

USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Cambridge in Seismic Design Category A: Lowest seismic design category. Building code requires no seismic-specific detailing here beyond ordinary construction practice. That puts Cambridge in the 15th percentile nationally for seismic hazard - higher than 15% of the 4,875 US cities USGS was checked against here.

How Cambridge compares

The raw figures: peak ground acceleration 0.055g, short-period spectral response 0.11g, 1-second spectral response 0.04g. Among 46 Maryland cities in this dataset, Cambridge ranks 42 for seismic hazard, the 9th percentile within the state. About 13,262 people live in Cambridge, Maryland.

Bracing and bolting: the actual cost

Outside California, no state-level retrofit grant equivalent to Brace + Bolt could be found for Maryland. 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 Cambridge address.

More on how this number was built

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