METHODOLOGY
Every number
has a source.
Every score on this site is computed from NYC Open Data. No proprietary models. No black boxes. This page explains exactly how.
COMPOSITE SCORE
7 weighted components. All public.
Higher = worse. Each building gets a composite score from 7 weighted components, each drawn from a different public dataset.
| Component | Weight | Source |
|---|---|---|
| HPD Violations per unit (5yr) | 20% | HPD Open Data |
| DOB Violations per unit (5yr) | 15% | DOB Open Data |
| Active litigation rate per 100 buildings | 15% | NYSCEF |
| Cumulative LL11 assessment $/unit (10yr) | 20% | DOB LL11 FISP |
| Engineer-contractor independence violations | 10% | Cross-reference LL11 filings |
| 311 complaint rate per unit (5yr) | 10% | NYC 311 |
| Reserve fund adequacy ratio | 10% | Financial snapshots |
VIOLATION WEIGHTING
Not all violations are equal.
HPD classifies violations by severity. We weight them accordingly.
| Class | Meaning | Score |
|---|---|---|
| C | Immediately hazardous | 50 pts |
| B | Hazardous | 8 pts |
| A | Non-hazardous | 1 pt |
| Open NOV | Unresolved condition | 12 pts |
FACADE SCORING
LL11 / FISP penalties.
| Finding | Score |
|---|---|
| UNSAFE filing | 25 pts |
| No Report Filed | 5 pts |
| Per $1,000 in penalty fees | 1 pt |
311 COMPLAINTS
Resident complaint scoring.
| Category | Score |
|---|---|
| Lead paint | 4 pts |
| Rodent | 2 pts |
| Water leak / water system | 1.5 pts |
| All other housing complaints | 0.1 pts |
TEMPORAL ANALYSIS
Every violation carries a date.
We compute date range, last 12 months, last 24 months, active vs resolved, year-over-year counts, and heating-season clustering. Trend matters more than a single snapshot.
THRESHOLDS
Minimum requirements to be ranked.
DATA SOURCES
All public. All free.
| Source | What It Provides |
|---|---|
| HPD Violations | Class A/B/C violations with dates and status |
| HPD Registrations | Building registration with BIN/BBL/address |
| HPD Registration Contacts | Registered agents and officers |
| DOB Violations | Building code violations |
| LL11 FISP Filings | Facade inspection status and penalty fees |
| 311 Service Requests | Resident complaints by category |
| ACRIS Real Property | Deeds, mortgages, sale prices |
| PLUTO | Owner names, unit counts, year built |
| NYSCEF | Supreme Court litigation by party name |
VERSIONING
Scores have history.
This methodology is versioned. Score history is preserved across versions. Changes are announced 30 days before taking effect.
Current version: 1.0 — Effective 2026-04-11 — Reviewed annually