Across 1,517 permits filed since 2025-03-12, the median is $10,322; half of projects fall between $4,500 and $18,000. 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
- replace boiler with EMP-182-TB boiler; replace oil tank in basement with new tank in same locationTown of Greenwich · 2026-09-10$22,451
- replace Burnham AL50SL water heater; indirect storage tankTown of Greenwich · 2026-09-10$5,000
- replace 275 gal. oil tank in basement; oil line to boiler is newer (pre-existing) and is to remainTown of Greenwich · 2026-09-10$7,358
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 Fairfield County, CT came in between $4,500 and $18,000. 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
Boiler / water heater in New JerseyBoiler / water heater in New YorkBoiler / water heater in ConnecticutBoiler / water heater on Long Island