Across 234 permits filed since 2025-01-25, the median is $50,000; half of projects fall between $10,088 and $200,000. 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 Westchester County, NY actually reported when they pulled permits.
Recent filings
- Addition issued to New Front Porch, Second Floor Addition includes 4 Bedrooms, 3 Baths, Laundry & Rec. Room. Rebuild First Floor over existing foundation per Variance Granted #26-13City of Rye · 2026-07-24$750,000
- CONSTRUCT A SECOND-FLOOR ADDITION AND ALTERATIONS TO AN EXISTING ONE-FAMILY DWELLING AS SHOWN ON THE SUBMITTED PLANS WITH THE CONDITIONS LISTED BELOWCity of Yonkers · 2026-07-21$150,000
- PROPOSED ALTERATIONS AND ADDITION TO CONVERT EXISTING ONE FAMILY TO A TWO FAMILYCity of Yonkers · 2026-07-20$200,000
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 $10,088 and $200,000. 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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