173 4 Avenue, Brooklyn
A 1920 mixed residential and commercial building on 4 Avenue carrying 2.02 FAR of unused residential development rights on record under its C4-4D zoning.
173 4 Avenue is a mixed residential and commercial building in Brooklyn, New York City (BBL 3009490011). The property is zoned C4-4D, on a 1,375 sq ft lot, with 4 floors and 4 residential units. It was built in 1920. The lot is not inside a FEMA Special Flood Hazard Area. NYC municipal records show 20 open building violations for this lot as of 2026-07-05.
Property facts
| BBL | 3009490011 |
|---|---|
| Borough | Brooklyn — Community District 6 |
| Neighborhood | Park Slope |
| ZIP code | 11217 |
| Zoning district | C4-4D |
| Building class | S3 — mixed residential and commercial building (what’s a building class?) |
| Land use | 04 — Mixed residential & commercial buildings |
| Lot area | 1,375 sq ft |
| Floors | 4 |
| Residential units | 4 |
| Year built | 1920 |
| FAR | 4 built · 6.02 max residential · 3.4 max commercial Learn: What is FAR? |
| Flood zone | Not in a FEMA Special Flood Hazard Area |
Public records
- 2 open Department of Buildings violations
- 1 open ECB (OATH) violation
- 17 open Housing Preservation & Development violations
Violation counts as of 2026-07-05.
Absence of a record means none on file in NYC municipal records — not a certification of compliance.
The complete dossier also covers:
- Buildable floor area (residential & commercial)
- Recorded ownership & last sale
- Recorded mortgages & open debt stack
- LL97 carbon exposure by compliance period
- Flood coverage percentage & base flood elevation
- Climate projections for this lot
- Open permits & construction pipeline
- Distress signal convergence
- Air rights & transferable development rights
- Comparable sales (Pro)
Nearby on this block
Data: NYC municipal records (Departments of City Planning, Buildings, Finance) and FEMA. See our sources and methodology. Data as of 2026-07-11.