Across 112 permits filed since 2025-05-03, the median is $225,000; half of projects fall between $107,500 and $512,500. 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
- Church service w/Tents. Utilities: Electricity. Day Event: 11/02/26. Insp. Date: 10/31/26 1 PM Occupant Load: 420 Fire Watch: Not Required ELE: Electrical work for special event: Podium, plug-in extension cord from building for church servTown of Greenwich · 2026-10-30$5,500
- Proposed 2nd floor addition over existing garage.Town of Greenwich · 2026-10-27$325,000
- Adding 1 gym, 1 office, 1 bathroom in a second story addition.Town of Greenwich · 2026-10-27$225,000
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 $107,500 and $512,500. 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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