New Castle's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, New Castle is Category B. Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. Rank it against the rest of the country and New Castle sits at the 30th percentile for seismic hazard among 4,875 US cities.

How New Castle compares

USGS's underlying values for New Castle: 0.05g peak ground acceleration, 0.101g at short period, 0.045g at 1 second. Within Pennsylvania alone, New Castle ranks 111 of 193 cities by seismic hazard - the 43th percentile in-state. New Castle has a population of about 21,332.

Retrofit economics for New Castle

A full earthquake retrofit typically runs $5,000-$10,000 nationally (around $7,000 typical), driven mainly by house size and foundation type, not by Pennsylvania specifically. California's Earthquake Brace + Bolt grant, which covers a large share of this cost, is a California-only program and does not apply in Pennsylvania.

What this means for insurance

A New Castle homeowner cannot buy a standalone earthquake policy in most cases - it is added to an existing homeowners policy as an endorsement, so the place to start is a regular home-insurance quote.

Where New Castle's figures come from

New Castle's Category B and every number above trace to USGS's own ASCE 7-16 Design Maps service - see the methodology guide. See the category explainer for what Category B does and doesn't tell you about New Castle.