Across 393 permits filed since 2025-03-10, the median is $55,000; half of projects fall between $10,000 and $239,999. 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 Fairfield County, CT actually reported when they pulled permits.
Recent filings
- KITCHEN EXHAUST PIPPING, DUCTWORK RELOCATION, ADD SUPPLY VENTS ON NEW ADDITION, ADD AIR HANDLER AND CONDENSER IN BASEMENTWestport · 2026-09-09$12,000
- 2 story addition, front bump out for porch and garage.Town of Greenwich · 2026-09-08$300,000
- 2 STORY ADDITION FOR KITCHEN EXTENSION / 2ND STORY BEDROOMS AND BATHROOMWestport · 2026-09-08$145,000
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 Fairfield County, CT came in between $10,000 and $239,999. 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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