Across 1,028 permits filed since 2025-01-25, the median is $15,000; half of projects fall between $5,000 and $92,022. Figures are permit valuations reported to building departments. National cost guides answer this question with averages from other markets; these numbers are what homeowners in Connecticut actually reported when they pulled permits.
Recent filings
- Wiring for new shed dormer extension, install lighting and outlets for storage area. Relocate wiring for AC unitCity of Milford · 2026-07-24$2,500
- Installing 1 sump pump, 1 yard well, 15 LNFT of downspout extensions, and 5 LNFT buried discharge lineCity of Milford · 2026-07-24$5,948
- Addition-2 lavatory sinks, 1toilet, and1showerCity of Norwalk · 2026-07-23$9,400
How to read these numbers
Permit valuations are the project cost the applicant reports to the building department. They skew slightly low — nobody rounds up for the permit fee — and scope varies, so the middle-half range is the honest picture: half of all home addition permits in Connecticut came in between $5,000 and $92,022. We exclude permits under $1,000, jobs filed as whole-house construction, and counties whose building departments don't reliably report valuations.