Across 625 permits filed since 2025-04-25, the median is $17,127; half of projects fall between $8,000 and $45,000. 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 Fairfield County, CT actually reported when they pulled permits.
Recent filings
- Install sub floor trench drain basement waterproofing system to sump pump, install one well duct window drain, install 1/2 wall system (vapor barrier), rough wall cuts for trench drain accessCity of Norwalk · 2026-10-23$8,000
- Strip existing siding, apply house wrap, 1/2 inch insulation, and new vinyl siding 30.8 squares total whole home. Apply custom aluminum trim to all window and door casings, fascia and rake, apply invisivent soffit to all eaves where applicFairfield · 2026-10-22$27,500
- Replace two windows - no framingCity of Norwalk · 2026-10-21$3,500
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 window replacement permits in Fairfield County, CT came in between $8,000 and $45,000. 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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