Across 47 permits filed since 2025-03-12, the median is $13,000; half of projects fall between $4,650 and $29,850. 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 New London County, CT actually reported when they pulled permits.
Recent filings
- Installing Mitsubishi ductless mini split in home. Wall cassettes will be installed in main living area, basement rec room, and in two bedrooms. Condenser will be located at south side of house.Montville · 2026-09-03$15,900
- rewire basement for finished space. Outlets, Lights, new circuits. Wiring electric heat in the basement.Town of Waterford · 2026-08-20$1,200
- FINISH HALF OF BASEMENT FOR OFFICE/RECROOMTown of Waterford · 2026-08-18$13,000
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 basement finishing permits in New London County, CT came in between $4,650 and $29,850. We exclude permits under $1,000, jobs filed as whole-house construction, and counties whose building departments don't reliably report valuations.
Same project, other places
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