Across 650 permits filed since 2025-04-24, the median is $28,000; half of projects fall between $12,534 and $110,384. 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
- 12 X 20 REAR DECKFairfield · 2026-10-23$15,000
- Re-deck existing deck in kind. New 8' x 14' freestanding swim spa insert withing deck footprint. New concrete slab at grade for swim spa within deck footprints.Town of Weston · 2026-10-20$75,000
- 1st floor mudroom and sunroom (Building over deck and patio). Second floor renovation throughout.Town of Greenwich · 2026-10-20$475,000
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 deck permits in Fairfield County, CT came in between $12,534 and $110,384. 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
Deck in New JerseyDeck in New YorkDeck in ConnecticutDeck on Long Island