Across 470 permits filed since 2025-05-02, the median is $55,000; half of projects fall between $13,200 and $189,669. 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 Westchester County, NY actually reported when they pulled permits.
Recent filings
- NEW WOOD PERGOLA, OUTDOOR KITCHEN, STONE PATIO EXTENSION, GARDEN WALLS NOT TO EXCEED 48" HT.Town of Pound Ridge · 2026-10-29$65,000
- Proposed two story addition, 2nd story addition over existing footprint and renovations to existing single family dwelling house.Town of North Castle · 2026-10-29$600,000
- ADD AN ADDITION TO EXISTING RESIDENCE TO INCLUDE A MASTER BEDRM, NEW ENTRY, A NEW DETACHED ONE-STORY GYM, A DETACHED ONE-STORY GARAGE, & MODIFY AN EXISTING DRIVEWAY & SEPTIC SYSTEM. MUST COMPLY WITH PB APPROVALS. (1) AS-BUILT SURVEY REQ FORTown of Pound Ridge · 2026-10-28$1,500,000
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 Westchester County, NY came in between $13,200 and $189,669. 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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