C6-3A Zoning District — New York City

Roughly 370 tax lots carry this designation on record, and their buildings are substantially prewar: 79% predate 1940, the median construction year is 1920, and only 5% of the stock dates from the 1945-to-1975 boom. Construction since 2000 is more visible, at 14% of recorded buildings — newer than the boom era's contribution, though still a minority of the whole. The 5% boom-era share sits well behind the 14% recorded since 2000, meaning more of this designation's stock has gone up in recent decades than during the postwar boom itself.

Condominium classifications lead the recorded building types at 24% of the mix, with mixed residential-commercial buildings at 16% and elevator apartment buildings at 13%. By land use, mixed residential-and-commercial use covers 54% of lots, commercial-and-office use 12%, and multi-family elevator buildings 9%. Residential use overall reaches 72% of lots, and the records count 9,331 homes across the designation, a substantial population for roughly 370 lots.

Lots run to a median of 3,687 square feet, with the 90th percentile at 14,466, and buildings rise to a median of 5 stories, with 33% recorded above 6 floors. A recorded 11% of these lots also sit inside a designated historic district — a real share of landmark review layered on top of the zoning — while 4% fall inside the mapped Special Flood Hazard Area. Neither overlay is universal here, but both are large enough to matter on a meaningful share of the roughly 370 lots.

On the development ledger, 80% of lots record floor area below their allowance, with a median residual of 3 FAR. That headroom sits against a stock that is already 79% prewar and partly under historic review, a combination that shapes what building on any one lot would involve in practice. The governing FAR, height, and use rules are in the tables above with their citations, and the historic and flood status of a specific address is tracked at the individual lot level, not only as a designation-wide share.

This designation's file carries a full read on every stat family tracked here, with nothing nulled for coverage. That matters because the historic-district share, at 11%, sits on top of a stock that is already 79% prewar, a combination worth checking lot by lot rather than assuming applies evenly across all 370 lots on record. Each lot's own recorded historic and flood-map status is checkable individually, drawn from the same complete file as the shares cited above.