Across 43 permits filed since 2025-01-28, the median is $12,000; half of projects fall between $4,650 and $30,250. 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
- Finishing basement to include bedroom, study and tv room.Montville · 2026-06-30$29,700
- Wire remodeled basement to code for outlets, switches, cable, recessed lights, carbon monoxide/smoke detector combo, sub-panel, bath vent/light combo, GFI outlet, thermostats and electric baseboard heat.Montville · 2026-06-25$4,300
- 30kWh energy storage to be paired with existing on-site solar PV system. BO NOTES: BATTERY SYSTEM CANNOT BE WITHIN 3 FEET OF ANY OPENING ON THE BUILDING. R328.4 Locations ESS shall be installed only in the following locations: Detached gaMontville · 2026-06-23$36,760
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 $30,250. 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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