21 West 34 Street, Manhattan 10001 is a 6,897 square foot lot zoned C5-3. RunEnvelope’s engine finds an as-of-right scheme with homes of 80,464 sf (UAP (City of Yes)), against 19,054 sf built on the lot today.
That leaves 61,410 sf more floor area than stands here now, if the existing building were replaced. The largest scheme with homes and no affordability obligation holds 68,970 sf (Max Apartments).
City Planning’s PLUTO file lists a residential FAR of 10.00 for this lot, which at 6,897 sf of land is 68,970 sf. The engine’s largest residential-only scheme without an affordability obligation (Max Apartments) holds 68,970 sf, close to that simple multiplication.
The largest 6 as-of-right schemes RunEnvelope’s engine produced for this lot, by zoning floor area. A full study also models the building itself: floor plates, heights, setbacks, unit mix and parking.
| Scheme | Type | Floor area | FAR | Homes |
|---|---|---|---|---|
| Community Facility | Community facility | 103,455 | 15.00 | None |
| UAP (City of Yes) | Income-restricted housing | 80,464 | 11.67 | 89 |
| AIRS Senior Housing (100% Affordable) | Income-restricted housing | 80,124 | 11.62 | 89 |
| Max Apartments | Housing | 68,970 | 10.00 | 144 |
| Max Residential (Sky Exposure Plane) | Housing | 68,970 | 10.00 | 78 |
| Commercial Overlay | Mixed use with homes | 68,961 | 10.00 | 72 |
Floor area is zoning floor area in square feet. Highlighted: the largest scheme with homes. Income-restricted schemes (Universal Affordability Preference, AIRS senior housing) require a share or all of the homes to be affordable. Shared housing counts rooms, not apartments. Schemes that need a landmark transfer of development rights, the FRESH food store bonus or a stack of every program are left off this page; the full study shows them.
As-of-right only: what the Zoning Resolution allows without a variance, special permit or rezoning. Computed by RunEnvelope’s zoning engine on October 24, 2026 from PLUTO 26v2 lot data, in screening mode: the engine uses the City’s recorded lot area and dimensions, not a surveyed lot outline.
This is not a professional opinion, an appraisal or a statement that anything will or should be built here. Existing tenants, leases and the owner’s plans are not part of it.
Why this lot has a page: we publish pages only for lots that clear a set of data quality and headroom tests.
The closest published lots in Manhattan, same zoning district first. All Manhattan lots.