Across 357 permits filed since 2025-03-10, the median is $11,000; half of projects fall between $5,000 and $17,845. 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
- REPLACE 40 GL NG WATER HEATERCity of Norwalk · 2026-09-03$2,000
- CHIMNEY LINER-INSTALL ONE 6" 316 STAINLESS STEEL LINER INTO HEATING FLUE TO SERVE ONE OIL FIRED BOILER WITH 7" BREECHING. INSULATE LINER WITH CHI MIX+CAP WITH 6" LINER CAPCity of Norwalk · 2026-09-02$4,460
- DIRECT REPLACEMENT OF EXISTING OIL FIRED BOILER WITH NEW OIL FIRED BOILER IN SAME LOCATIONCity of Norwalk · 2026-09-02$15,445
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 boiler / water heater permits in Norwalk, CT came in between $5,000 and $17,845. 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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