Does Carlstadt, NJ need an earthquake retrofit?
USGS's ASCE 7-16 seismic design model - the same standard building codes use - places Carlstadt in Seismic Design Category B: Low seismic hazard. Code requires basic seismic detailing (bracing, connections) but no special structural system restrictions. That puts Carlstadt in the 65th percentile nationally for seismic hazard - higher than 65% of the 4,875 US cities USGS was checked against here.
Carlstadt by the numbers
USGS's underlying values for Carlstadt: 0.182g peak ground acceleration, 0.294g at short period, 0.061g at 1 second. Within New Jersey alone, Carlstadt ranks 43 of 194 cities by seismic hazard - the 78th percentile in-state. Carlstadt has a population of about 6,454.
What a retrofit costs in Carlstadt
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 New Jersey 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 New Jersey.
Insuring against this, not just retrofitting
A Carlstadt 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 Carlstadt's figures come from
Carlstadt'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 Carlstadt.