R4B Zoning in NYC: Low-rise, one- and two-family
R4B districts are low-density districts permitting one- and two-family homes including rowhouse forms, with slightly more floor area than R3. Citywide, 15,447 tax lots carry a primary R4B designation.
On the average R4B lot, roughly 25% of the allowed residential floor area is unused — the raw material of a rezoning-era investment thesis. Infill and two-family product works here; look for lots where built floor area sits well below what the district allows.
Where R4B lots are
FAQ
What is R4B zoning in NYC?
R4B is one of low-density districts permitting one- and two-family homes including rowhouse forms, with slightly more floor area than R3. Across New York City, 15,447 tax lots carry a primary R4B designation.
How built-out are R4B lots today?
On average, R4B parcels are built to a floor-area ratio of 0.75 against an average maximum residential FAR of 1 — roughly 25% of allowed floor area is unused on the average lot. Individual lots vary widely; check any specific parcel on the free NYRezone map.
Does City of Yes affect R4B parcels?
15,447 R4B parcels flag as potentially affected by at least one City of Yes for Housing Opportunity program in NYRezone's screening model. Program applicability is parcel-specific — verify each lot.
Screen every R4B parcel free
The NYRezone map scores all 15,447 R4B lots on unused floor area, City of Yes eligibility, and assemblage potential. No login.
Related R4 districts
Parcel figures derive from NYC Department of City Planning PLUTO data as processed by NYRezone. Zoning regulations are summarized for orientation only — always verify specifics in the NYC Zoning Resolution and with the Department of City Planning before acting on any parcel.