Newcastle's Seismic Design Category, explained

Under the seismic model IBC and ASCE 7 use for new construction, Newcastle 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. Rank it against the rest of the country and Newcastle sits at the 93th percentile for seismic hazard among 4,875 US cities.

Newcastle by the numbers

USGS's underlying values for Newcastle: 0.603g peak ground acceleration, 1.412g at short period, 0.487g at 1 second. Within Washington alone, Newcastle ranks 18 of 125 cities by seismic hazard - the 86th percentile in-state. Newcastle has a population of about 13,072.

What a retrofit costs in Newcastle

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 Washington 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 Washington.

Insuring against this, not just retrofitting

A Newcastle 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 Newcastle's figures come from

Newcastle's Category D 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 D does and doesn't tell you about Newcastle.