Everyone agrees the city needs more homes. Far fewer people can tell you where they would go. So we checked all 858,284 properties in the five boroughs, one by one, and counted the ones with real room to build.
The short answer: about 5,768 places, with room for roughly 613,000 homes. That is a lot less than the numbers you usually hear, and the biggest group of them is not what almost anyone guesses.
homes. You get this by taking every property in the city, working out how much bigger the zoning would let the building be, and adding it all up.
The trouble is that most of that total is a few feet of spare room above somebody’s house in Queens. Nobody is going to demolish a family home to add half a bedroom. Counting it tells you nothing about where housing can go.
homes, across 5,768 properties. These are the ones where the spare room is big enough to be an actual building — at least 20,000 square feet of it, which is roughly a 25-home apartment block.
They are privately owned, big enough to build on, and currently used at less than half of what the zoning allows.
New York publishes a file describing every property in the city — all 858,284 of them — including how big the lot is, how big the building on it is, and how big the zoning would let that building be. We start there.
For each property, the spare room is simply the difference: what the zoning allows, minus what is already there. Then we throw most of it away. A property only stays in if all of these are true:
What survives is substantial. The typical site is a quarter of an acre with enough spare room for about 45 homes. These are real buildings, not slivers.
Where we drew the lines is a judgement call. The 2,500 square foot minimum, the half-full test and the 20,000 square foot floor are choices, not discoveries. Pick different ones and you get a different number. We spell ours out so anyone can disagree with the choice rather than argue with a total whose definition is hidden.
| Borough | Sites | Spare room | Homes it could hold |
|---|---|---|---|
| Queens | 1,449 | 128M sf | 188K |
| The Bronx | 1,400 | 91M sf | 133K |
| Manhattan | 1,321 | 79M sf | 116K |
| Brooklyn | 1,093 | 75M sf | 111K |
| Staten Island | 505 | 44M sf | 65K |
| All five boroughs | 5,768 | 417M sf | 613K |
Queens has the most. Manhattan has fewer sites than the Bronx, but each one holds more, which is what you would expect — what Manhattan is short of is land, not permission to build on it.
Ask where New York has room to build and almost everyone says empty lots. Empty lots come second. The biggest group by far is ordinary commercial property: the one and two storey shops, strip malls and car washes lining avenues where the rules would allow a building six or ten times the size.
That matters for anyone trying to fix this. A programme aimed at empty lots reaches 864 of these places. One that makes it easier to put flats above a shop reaches 2,226 — nearly three times as many.
New York sorts land into zoning districts, each with its own rules; R6 and R7 are the mid-rise ones you see on most outer-borough avenues. That is where the room is. It is not a handful of skyscraper sites waiting to happen — it is spread across ordinary blocks, with these five districts holding 1,618 of the 5,768 sites. Every district has its own page with its bulk rules and its own count.
This counts what the rules permit. It does not predict what gets built, and the gap between those two is enormous. Five things this analysis cannot see:
The City’s record of how big each existing building is comes from tax records, and it is least reliable on exactly the odd, irregular properties this study most wants to find. So treat any single property here as a lead worth checking, not a fact. The only way to know what one of them holds is to model it properly.
A privately owned property of at least 2,500 square feet, where housing is allowed, where the current building uses less than half the space the rules permit, and where the spare room adds up to at least 20,000 square feet — roughly a 25-home building. Developers call these soft sites. Where we set those thresholds is a judgement call, and we state them so anyone can move them and count again.
Because those add up every scrap of spare room on every property in the city, including a few feet above a family house in Staten Island. That gets you about 4.7 million homes. The arithmetic is right; it just is not describing anything anyone could build. Keep only the places where the spare room is big enough to be a building and you are left with 5,768.
No, and it is important not to read it that way. This is what the rules allow, converted to homes at about 680 square feet each. It ignores landmarks, the people living and working there now, ground conditions, the shape of the lot, whether anyone can finance it, and whether the owner has any interest in selling. It is a ceiling, not a forecast.
Mostly under low commercial buildings. 2,226 of the 5,768 sites are shops, offices and similar — overwhelmingly one and two storey buildings on avenues zoned for far more. Empty lots are second at 864, and parking lots third at 544. Put plainly: New York's largest untapped housing supply is the space above its shopfronts.
Analysis run October 2026 against PLUTO 26v2 using the floor area tables in the Envelope zoning engine. Figures are point-in-time and are not updated as PLUTO changes. Reuse them with attribution and a link to this page.