Across 95 permits filed since 2025-03-03, the median is $350,000; half of projects fall between $137,500 and $575,000. 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
- Proposed single story addition to dining room @ rear facade 8' x 17'-3".Town of Greenwich · 2026-08-26$150,000
- Renovation and two story addition. Demo permit 26-1971Town of Greenwich · 2026-08-12$630,000
- Expand foundation and build addition to front of house (required front yard setback variance). Renovate home and expand driveway.Town of Greenwich · 2026-08-06$700,000
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 home addition permits in Greenwich, CT came in between $137,500 and $575,000. 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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