Across 125 permits filed since 2025-03-12, the median is $18,562; half of projects fall between $2,000 and $100,000. 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 Erie County, NY actually reported when they pulled permits.
Recent filings
- To an existing 2 story 1 family dwelling install concrete patio extension 8ft x 43ft to an existing patio.Buffalo · 2026-09-04$5,800
- Kitchen addition to rear of existing single-family dwelling, reconfiguration of interior to add full bath and laundry room. *** Digeplan *** Buffalo · 2026-09-01$100,000
- NEW BUILD (ADDITION)Buffalo · 2026-08-25$130,000
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 Erie County, NY came in between $2,000 and $100,000. 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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