NYC’s Housing Preservation and Development (HPD) tracks every housing code violation filed against landlords. Using data from NYC Open Data covering 808,517 currently open violations across 89,291 buildings, we graded every building in the city on a scale of A through F based on open violation severity — with Class C (immediately hazardous) violations weighted most heavily.
Of the 89,291 buildings with open HPD violations, 2,957 received a Grade F — the lowest possible rating. These buildings average 98.8 open violations each, including an average of 33 Class C violations per building. Class C violations include no heat or hot water, active mold, lead paint exposure, and other conditions classified by HPD as requiring immediate correction.
Below are the 10 buildings with the highest Class C open violation counts in NYC.
How We Score Buildings
The accountability score (0–100) is calculated from currently open violations:
Score = 100
− MIN(60, Class C open × 3)
− MIN(25, Class B open × 0.5)
− MIN(10, Class A open × 0.1)- Grade A (score ≥ 85): Few or no Class C violations
- Grade F (score < 40): High volume of immediately hazardous open violations
All data is from NYC HPD via NYC Open Data, filtered to violations with status = Open as of June 2025.
The 10 Buildings With the Most Class C Open Violations
1. 140 Park Hill Avenue, Staten Island
Open violations: 815 | Class C: 285 | Class B: 417 | Score: 5/100
The single building with the most Class C open violations in all of New York City sits on Park Hill Avenue in St. George, Staten Island. With 285 immediately hazardous violations and 417 hazardous Class B violations, this address carries some of the most severe unresolved housing conditions in the five boroughs.
2. 1720 Bedford Avenue, Brooklyn
Open violations: 410 | Class C: 271 | Class B: 125 | Score: 13.6/100
Located in Prospect Heights, this Brooklyn building has 271 Class C violations open — conditions classified by HPD as posing an immediate risk to residents. With only 14 Class A violations, the distribution skews almost entirely toward the most serious categories.
3. 530 East 169 Street, Bronx
Open violations: 794 | Class C: 263 | Class B: 464 | Score: 8.3/100
This Morrisania address in the Bronx has the second-highest total open violation count on this list, with 794 open violations — 263 of which are Class C. The sheer number of open Class B violations (464) indicates conditions that HPD considers hazardous but not yet immediately life-threatening.
4. 1022 East 93 Street, Brooklyn
Open violations: 890 | Class C: 256 | Class B: 504 | Score: 5/100
The building with the most total open violations in our dataset — 890 open violations — is located in East Flatbush, Brooklyn. Of those, 256 are Class C and 504 are Class B. With a score of 5/100, this address receives the lowest possible effective grade.
5. 85 Willis Avenue, Bronx
Open violations: 746 | Class C: 239 | Class B: 383 | Score: 5/100
In Mott Haven — one of the Bronx neighborhoods with the highest concentration of Grade F buildings — 85 Willis Avenue has 239 immediately hazardous violations still unresolved. Mott Haven has historically had among the highest HPD violation density in the city.
6. 240 Park Hill Avenue, Staten Island
Open violations: 672 | Class C: 236 | Class B: 371 | Score: 8.6/100
Two buildings on Park Hill Avenue in St. George appear in our top 10 — #140 and #240. The Park Hill Apartments complex has long been documented as one of Staten Island’s most troubled housing developments. Combined, the two buildings have 521 Class C violations open.
7. 1726 Davidson Avenue, Bronx
Open violations: 460 | Class C: 228 | Class B: 191 | Score: 11/100
Located in Fordham, the Bronx, this building has 228 Class C violations open. The ratio of Class C to total violations (228 out of 460 = 49.6%) is the highest on this list, meaning roughly half of all open violations at this address are immediately hazardous.
8. 2026 Nostrand Avenue, Brooklyn
Open violations: 452 | Class C: 227 | Class B: 184 | Score: 11.1/100
Flatbush has one of Brooklyn’s highest concentrations of Grade F buildings. At 2026 Nostrand Avenue, 227 Class C violations remain unresolved — conditions like lack of heat, hot water, or pest infestations that HPD mandates be fixed immediately.
9. 883 East 180 Street, Bronx
Open violations: 507 | Class C: 225 | Class B: 256 | Score: 12.4/100
In the Belmont neighborhood of the Bronx, this building carries 507 open violations total — 225 of which are Class C. The Bronx accounts for more Grade F buildings than any other borough (1,247 Grade F buildings), and addresses like this one illustrate why.
10. 33 West 89 Street, Manhattan
Open violations: 452 | Class C: 223 | Class B: 187 | Score: 11/100
The only Manhattan address in our top 10 sits on the Upper West Side — a neighborhood more commonly associated with high rents than with HPD violations. Yet 33 West 89 Street has 223 Class C violations open. High property values do not correlate with landlord accountability.
By the Numbers: Grade F Across NYC
| Grade | Buildings | Avg Open Violations | Avg Class C |
|---|---|---|---|
| F | 2,957 | 98.8 | 33.2 |
| D | 1,361 | 42.0 | 13.6 |
| C | 2,511 | 30.0 | 9.6 |
| B | 5,747 | 18.1 | 5.5 |
| A | 76,715 | 3.6 | 0.4 |
Grade F buildings represent just 3.3% of buildings with open violations, but account for a disproportionate share of Class C conditions. The Bronx has 1,247 Grade F buildings — the most of any borough. Staten Island has only 44.
What Class C Violations Actually Mean
HPD classifies violations into three tiers:
- Class A — Non-hazardous (e.g., missing interior door hinge, peeling paint in non-lead building)
- Class B — Hazardous (e.g., broken window, defective heating system, vermin evidence)
- Class C — Immediately hazardous (e.g., no heat or hot water, lead paint in unit with child under 6, active mold, carbon monoxide detector missing, rodent infestation)
Landlords are legally required to correct Class C violations within 24 hours. When they remain open for months or years, it indicates the landlord is not complying with HPD orders.
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