145 East 42 Street, Manhattan 10017 is a 3,724 square foot lot zoned C5-3. RunEnvelope’s engine finds an as-of-right scheme with homes of 55,008 sf (Residential + Community Facility), against 10,721 sf built on the lot today.
That leaves 44,287 sf more floor area than stands here now, if the existing building were replaced.
City Planning’s PLUTO file lists a residential FAR of 10.00 for this lot, which at 3,724 sf of land is 37,240 sf. The engine’s largest residential-only scheme without an affordability obligation (Max Apartments) holds 37,241 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 |
|---|---|---|---|---|
| Max Commercial | Commercial | 55,860 | 15.00 | None |
| Community Facility | Community facility | 55,860 | 15.00 | None |
| Residential + Community Facility | Mixed use with homes | 55,008 | 14.77 | 26 |
| AIRS Senior Housing (100% Affordable) | Income-restricted housing | 44,688 | 12.00 | 41 |
| UAP (City of Yes) | Income-restricted housing | 44,688 | 12.00 | 29 |
| Max Apartments | Housing | 37,241 | 10.00 | 78 |
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 23, 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.