Across 228 permits filed since 2025-04-25, the median is $29,500; half of projects fall between $10,000 and $120,000. 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
- 1st floor mudroom and sunroom (Building over deck and patio). Second floor renovation throughout.Town of Greenwich · 2026-10-20$475,000
- Siding repairs & complete tear down and reconstruct rear deck. ARC approved 10/19/2026Town of Greenwich · 2026-10-19$150,000
- Adding deck.Town of Greenwich · 2026-10-16$5,000
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 deck permits in Greenwich, CT came in between $10,000 and $120,000. 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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