South San Francisco's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, South San Francisco is Category D. High seismic hazard - this is the category most of coastal California, the Pacific Northwest, and other active fault regions fall into. Code mandates significant seismic detailing and restricts irregular structural configurations. This is the category the Brace + Bolt scope (cripple-wall bracing, foundation bolting) is built for. Nationally, South San Francisco ranks above 96% of the 4,875 cities in this dataset for seismic hazard - the 96th percentile.

Where South San Francisco sits in California

The raw figures: peak ground acceleration 0.743g, short-period spectral response 1.723g, 1-second spectral response 0.702g. Among 429 California cities in this dataset, South San Francisco ranks 148 for seismic hazard, the 66th percentile within the state. About 64,660 people live in South San Francisco, California.

What a retrofit costs in South San Francisco

Because South San Francisco is in California, the EBB grant applies if the ZIP code participates and the house qualifies (wood-framed house on a raised (not slab-on-grade) foundation, built before 1980): a $3,000-$7,000 bracing-and-bolting job drops to $0-$4,000 after the $3,000 base grant, or effectively free for income-eligible households getting the full $10,000.

Earthquake insurance for a South San Francisco home

Earthquake coverage in California mostly runs through the California Earthquake Authority (CEA), sold only through licensed agents at CEA-participating insurers - there is no direct-to-consumer CEA policy. A general home-insurance quote is the practical starting point for a South San Francisco homeowner asking about it.

More on how this number was built

The methodology guide covers exactly how USGS's public design-maps API produced South San Francisco's numbers. The retrofit cost and grant guide covers every EBB eligibility rule, including the ones this page can't check.