Across 98 permits filed since 2025-03-07, the median is $22,030; half of projects fall between $10,000 and $106,262. 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 Norwalk, CT actually reported when they pulled permits.
Recent filings
- ELECTRICAL ALTERATIONS FOR RESIDENTIAL ADDITION INCLUDING BRANCH CIRCUITS, LIGHTING, SMOKE. CO DETECTION, CENTRALIZED LIGHTINGCity of Norwalk · 2026-09-04$1,000
- 2 STORY ADDITION (10'X20' +/-) AND RENO @ SFR INTERIOR - RELOCATION LAUNDRY - RENO 2 FULL BATHROOMS AND KITCHENCity of Norwalk · 2026-09-04$650,000
- SUPERSTRUCTURE FOR (2.5) STORY ADDITION (2) FULL BATHROOMS (2) BEDROOM OFFICE & TV ROOMCity of Norwalk · 2026-09-03$85,000
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 Norwalk, CT came in between $10,000 and $106,262. 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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