Across 26 permits filed since 2025-04-22, the median is $158,750; half of projects fall between $7,425 and $350,000. 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 Middlesex County, CT actually reported when they pulled permits.
Recent filings
- *Wire remodeled basement to code for outlets, switches, GFI outlets, carbon monoxide/smoke detector combo, recess lights, cable, wall sconce at top of stairs, smoke detector, utility lights, sub-panel, thermostats, dehumidifier and electricTown of Westbrook · 2026-10-21$7,000
- *Finish basement to code for rec room with wet bar and full bathroom with electric baseboard heat. State Modification Application for low beam 73 inches.(see comments) This project based on drawing submitted on October 20, 2026.Town of Westbrook · 2026-10-21$70,000
- Construction of single family dwelling with 3 bedrooms, 2 bathrooms, 1 car attached garage, attachec carport, covered patio, covered balcony on 2nd floor, unfinished basement, office on 2nd floorHigganum · 2026-10-16$375,000
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 Middlesex County, CT came in between $7,425 and $350,000. 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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