Across 109 permits filed since 2025-05-01, the median is $150,000; half of projects fall between $33,430 and $1,100,000. 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 Greenwich, CT actually reported when they pulled permits.
Recent filings
- Interior renovation in basement. Covering front porch/stoop.Town of Greenwich · 2026-10-16$80,000
- Basement renovation/playroom.Town of Greenwich · 2026-10-13$399,150
- upgrade service to 200 amp. from 150 amp.; upgrade light fixtures to LED in house; repair bathroom exhaust fans with mini split system; add low volt smoke to basement playroom. 6 swtchs., 20 fixtures (26 total devices). CRS: 2890216Town of Greenwich · 2026-10-09$4,800
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 Greenwich, CT came in between $33,430 and $1,100,000. 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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