R9X Zoning District — New York City
R9X is a contextual, high-density General Residence District (NYC Zoning Resolution § 11-122) in New York City.
R9X is a contextual, high-density General Residence District (NYC Zoning Resolution § 11-122) in New York City. It principally allows housing and community facilities. As of right, the maximum residential FAR is 9. 50 tax lots citywide carry R9X as their primary zoning designation.
Lots carrying this designation are concentrated almost entirely inside designated historic districts: 74% carry that status on record, among the highest historic shares in this file. The underlying stock is correspondingly old — a median construction year of 1888, with 86% of buildings predating 1940 — spread across a small footprint of roughly 50 tax lots citywide. None of these lots, 0%, sit inside the mapped federal flood zone.
What actually stands in this district
Historic-district status is the defining fact on record for this designation: 74% of its lots carry that status, among the highest concentrations of any designation profiled in this file. That layering of landmark review onto the zoning tracks an old building stock underneath — a median construction year of 1888, with 86% of recorded buildings predating 1940. The postwar decades barely registered here: only 8% of the stock dates from the 1945-1975 boom, and just 2% has been built since 2000, among the quietest recent-construction figures in this comparison set. Whatever new building has occurred on these roughly 50 lots has occurred at the margins of an already-old, already-protected fabric.
The recorded building classes split three ways without a dominant type: one-family homes lead at 26%, elevator apartment buildings follow closely at 22%, and mixed residential-and-commercial buildings add 20% — a stock that pairs detached and attached housing with a meaningful share of taller, elevator-served buildings. Land use runs more concentrated: 40% of lots carry a mixed residential-and-commercial designation, with one- and two-family use at 26% and multi-family elevator use at 16%. Altogether 86% of these lots are coded residential, and the file counts 928 homes across them — a modest total that reflects the small number of lots carrying this designation rather than low density on any one of them.
Lot sizes vary considerably against a fairly tight median: 2,000 square feet at the middle, but a 90th percentile of 15,306 square feet, pointing to a small number of much larger parcels among the more typical small lots — a common pattern where old, subdivided blocks sit alongside a handful of assembled or institutional-scale sites. Buildings run taller than the modest lot sizes might suggest: a median of 5 stories, with 27% of recorded buildings rising above 6 floors, a notably taller profile for a stock this old and this small in footprint.
By the federal flood map, none of these lots — 0% — sit inside the mapped Special Flood Hazard Area, a statement about the regulatory boundary rather than a ledger of which parcels have taken on water. Recorded floor area also runs well below file allowances across this designation: 88% of lots show a residual, with a median gap of 5.4 FAR, one of the wider recorded headroom figures in this file, though on a base of only about 50 lots, each parcel carries outsized weight in every share above. Each lot's own page carries its recorded specifics in full; the floor-area and height rules that actually govern this designation, with their citations, are set out in the rules tables above.
Bulk rules for R9X
| Context | Residential FAR | Community facility FAR | Max lot coverage | Heights | Citation |
|---|---|---|---|---|---|
| As of rightPer § 23-335: detached single/two-family residence requires two 5 ft side yards (a); for all other residences no side yards required (b). R6-R12 districts are predominantly multi-family; the dominant rule is 'no side yards required'. | Per § 23-362(a): max residential lot coverage 80% on interior/through lots; 100% on corner lots. Per § 23-362(b), eligible-site provisions cap at 65% (lots >= 30,000 sf) or 50% (large sites). | Per § 23-342(a): detached and zero-lot-line buildings require 20 ft rear yard at or below 75 ft (30 ft above 75 ft where permitted). Semi-detached and attached buildings on lots <40 ft wide require 30 ft; on lots >=40 ft wide, 20 ft at or below 75 ft. Per § 23-342(b), shallow interior lots (<95 ft deep, existing pre-12/15/1961) may reduce by 6 in per ft below 95 (min 10 ft). | 9 | 9 | 80% | — | NYC Zoning Resolution § 23-22, § 24-11 |
| As of right — narrow streetOn a narrow street beyond 100 ft of a wide street, or zoning lots with wide-street frontage beyond 100 ft; standard residences columns. Quality Housing envelope. | 9 | 9 | 80% | Base 60–125 ft · Max 165 ft | NYC Zoning Resolution § 23-22, § 23-432 footnote 2, § 23-431, § 24-11 |
| As of right — wide streetWithin 100 ft of a wide street; standard residences columns. Quality Housing envelope. Split required because §23-432 envelope differs from narrow-street variant. | 9 | 9 | 80% | Base 105–125 ft · Max 175 ft | NYC Zoning Resolution § 23-22, § 23-432 footnote 1, § 23-431, § 24-11 |
| Qualifying affordable housingPer § 23-22: 'Qualifying affordable housing' or 'qualifying senior housing' FAR (replaces pre-CoY per-MIH-area FAR columns; MIH program area details are in mih_program_areas table). | Per § 23-335: detached single/two-family residence requires two 5 ft side yards (a); for all other residences no side yards required (b). R6-R12 districts are predominantly multi-family; the dominant rule is 'no side yards required'. | Per § 23-362(a): max residential lot coverage 80% on interior/through lots; 100% on corner lots. Per § 23-362(b), eligible-site provisions cap at 65% (lots >= 30,000 sf) or 50% (large sites). | Per § 23-342(a): detached and zero-lot-line buildings require 20 ft rear yard at or below 75 ft (30 ft above 75 ft where permitted). Semi-detached and attached buildings on lots <40 ft wide require 30 ft; on lots >=40 ft wide, 20 ft at or below 75 ft. Per § 23-342(b), shallow interior lots (<95 ft deep, existing pre-12/15/1961) may reduce by 6 in per ft below 95 (min 10 ft). | 10.8 | 9 | 80% | Max 215 ft | NYC Zoning Resolution § 23-22, § 24-11 |
| Qualifying affordable housing — narrow streetOn a narrow street beyond 100 ft of a wide street; qualifying affordable housing / qualifying senior housing columns. | 10.8 | 9 | 80% | Base 60–155 ft · Max 215 ft | NYC Zoning Resolution § 23-22, § 23-432 footnote 2, § 23-431, § 24-11 |
| Qualifying affordable housing — wide streetWithin 100 ft of a wide street; qualifying affordable housing / qualifying senior housing columns. | 10.8 | 9 | 80% | Base 105–155 ft · Max 215 ft | NYC Zoning Resolution § 23-22, § 23-432 footnote 1, § 23-431, § 24-11 |
Values from the NYC Zoning Resolution, verified 2026-06-12; site-specific overlays, special districts, and waterfront rules can modify them — run a full lookup for a specific lot.
About residential districts
Residence districts principally allow housing and community facilities. Bulk rules in the NYC Zoning Resolution (§ 23-) control how much floor area a lot can carry and how tall and close to lot lines a building may be.
Contextual districts pair their floor-area ceilings with prescribed base and maximum building heights so new buildings mirror existing neighborhood form; non-contextual districts govern the envelope through more general height and setback rules, such as sky exposure planes. Commercial districts also allow residences under the rules of a residential-equivalent district, while manufacturing districts generally exclude new residences. Overlays and special purpose districts can modify any of this on a specific lot.
Example lots zoned R9X
- 976 Lexington Avenue — 15,121 sq ft lot, 13.81 built FAR, built 1955
- 889 Lexington Avenue — 17,071 sq ft lot, 7.88 built FAR, built 1906
- 895 Lexington Avenue — 17,071 sq ft lot, 7.87 built FAR, built 1907
- 28 East 36 Street — 17,350 sq ft lot, 7.38 built FAR, built 1949
- 35 East 35 Street — 15,306 sq ft lot, 8.69 built FAR, built 1955
- 975 Lexington Avenue — 10,039 sq ft lot, 8.85 built FAR, built 1927
- 943 Lexington Avenue — 7,532 sq ft lot, 9.12 built FAR, built 1924
- 944 Lexington Avenue — 7,833 sq ft lot, 9.8 built FAR, built 1916
- 901 Lexington Avenue — 5,925 sq ft lot, 10.11 built FAR, built 1907
- 955 Lexington Avenue — 6,353 sq ft lot, 8.61 built FAR, built 1924
- 34 East 35th Street — 17,373 sq ft lot, 11.98 built FAR, built 2025
- 962 Lexington Avenue — 4,033 sq ft lot, 3.78 built FAR, built 1910
R9X — quick questions
- What is the maximum residential FAR in R9X?
- 9, as of right, per NYC Zoning Resolution § 23-22, § 24-11. Site-specific overlays, special districts, and waterfront rules can modify it — run a full lookup for a specific lot.
- Is R9X a contextual district?
- Yes. R9X is a contextual district — its bulk rules pair floor-area ceilings with prescribed base and maximum building heights intended to mirror existing neighborhood form.
- How many tax lots are zoned R9X?
- 50 tax lots citywide carry R9X as their primary zoning designation, per NYC municipal records as of 2026-07-11.
- Are lots carrying this designation under historic-district review?
- Overwhelmingly, yes: 74% of these lots carry historic-district status on record, among the highest shares of any designation in this file.
- What era were these buildings recorded as built?
- Old, and largely settled decades ago: the median construction year is 1888, and 86% of recorded buildings predate 1940. Only 8% date from the 1945-1975 postwar boom, and just 2% have been built since 2000.
- What kind of housing stands on lots zoned this way?
- A mix without one dominant type: one-family homes lead the recorded classes at 26%, elevator apartment buildings follow at 22%, and mixed residential-and-commercial buildings add 20%. Overall 86% of these roughly 50 lots are coded residential, with 928 homes on record.
- Is there recorded floor-area headroom on these lots?
- Yes, on a small base: 88% of lots show recorded floor area below their allowance, with a median residual of 5.4 FAR. With only about 50 lots carrying this designation, each parcel moves that share more than it would on a larger designation.
- Do these lots sit inside the mapped flood zone?
- No: 0% of the lots carrying this designation fall inside the mapped federal flood zone, a statement about the regulatory map rather than a guarantee about water.
Keep learning
What do the R9X rules mean for a specific lot?
PearlAudit resolves the governing zoning for any NYC tax lot — district, overlays, special districts — and cites the Zoning Resolution section behind every rule claim.
District data: NYC municipal records (Department of City Planning) and the NYC Zoning Resolution. See our sources and methodology. Parcel data as of 2026-07-11.