Across 265 permits filed since 2025-03-07, the median is $16,000; half of projects fall between $4,600 and $55,000. 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 Hartford County, CT actually reported when they pulled permits.
Recent filings
- 21’1”x 19’1” multi-story home addition, 4’x 15’10” front porch extension, 16’x10’ laundry garage bay. A multi-story residential addition consisting of a new full foundation/basement expansion, an additional garage bay, a expanded front pTown of Southington · 2026-09-04$180,000
- Replacement of Furnace and evaporator coil in basement and condenser outdoors Your application for a Building Permit has been reviewed for compliance with the 2022 State of Connecticut Building Code. The permit for the proposed work is apSimsbury · 2026-09-01$6,500
- Wire remodeled basement to code for outlets, switches, cable, recessed lights, carbon monoxide/smoke detector combo, thermostats and electric baseboard heat.Town of Granby · 2026-08-27$2,400
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 basement finishing permits in Hartford County, CT came in between $4,600 and $55,000. 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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