Under NYC's Indoor Allergen Hazards Law, landlords of buildings with three or more units are legally required to inspect for mold, remediate it, and address the moisture source causing it. Here is what the law requires and what to do when they don't.
What the law requires
Local Law 55 of 2018 (NYC Administrative Code § 27-2017.1 through § 27-2017.11) requires owners of multiple dwellings with three or more units to:
| Obligation | What it means |
|---|---|
| Annual inspection | Inspect for mold and pest allergen hazards in occupied units and common areas annually |
| Remediation | Address any mold condition found, including addressing the underlying moisture source |
| Safe work practices | Use containment, protective equipment, and proper disposal during remediation |
| Licensed professionals | In buildings with 10 or more units: mold areas of 10 square feet or more require a NYS Department of Labor-licensed mold assessor and a separate NYS DOL-licensed mold remediator. In buildings with 3–9 units: safe work practices are required, but licensed assessors are not mandated under Local Law 55 |
| Notice | Provide written notice to tenants before and after remediation work |
How HPD classifies mold violations in apartments
The following thresholds apply to mold in a room within a dwelling unit:
| Class | Mold area in a room within a dwelling unit | Correction time |
|---|---|---|
| A — Non-hazardous | Less than 10 square feet | 90 days |
| B — Hazardous | 10–29 square feet | 30 days |
| C — Immediately hazardous | 30 square feet or more | 21 days |
How to get your landlord to act
Step one is written notice. Email or letter to your landlord describing the mold location, when you first noticed it, and requesting remediation in writing. Keep the response.
If the landlord does not act within a reasonable time, file an HPD complaint through 311. Category: Mold. HPD may inspect the condition and, if a violation is found, issue the appropriate violation.
Check your building's record first
Pull up your building on Weverit before filing. HPD mold violations appear in the violation history. A building with a pattern of unresolved mold complaints tells you something about how the landlord operates.
What your building's mold complaints look like, by the numbers
HPD received 37,830 mold and indoor allergen complaints citywide in the past 12 months. The three ZIPs with the most complaints: 11226 (Flatbush), 10458 (Belmont/Fordham), 10457 (East Tremont). Source: NYC 311 / HPD Open Data, Weverit analysis.
If the landlord fails to act after HPD issues a violation
Depending on the condition and enforcement history, HPD may arrange emergency repairs through its Emergency Repair Program and bill the owner.
If the mold condition is severe and ongoing, your options may include a rent abatement claim or an HP action in Housing Court to compel repairs. Both require documentation and are fact-specific.
Three things to document
First, photograph the mold with a ruler in frame. The size threshold matters for what remediation is required.
Second, document the moisture source if visible: a leaking pipe, condensation, water staining. Mold without a fixed moisture source will return.
Third, keep every written communication with your landlord about the condition.
Sources: NYC Administrative Code § 27-2017.1–§ 27-2017.11 (Local Law 55 of 2018); Local Law 61 of 2018; NYC HPD — Indoor Allergen Hazards: nyc.gov/site/hpd/services-and-information/indoor-allergen-hazards-mold-and-pests.page
Buildings with open mold violations
Ranked by open mold violations, from reports computed between August 16, 2026 and September 3, 2026.
- 186 Stockholm StreetBrooklyn F
- 371 Van Name AvenueStaten Island D
- 48-10 111 StreetQueens D
- 1402 Brooklyn AvenueBrooklyn C+
- 1820 East 13 StreetBrooklyn D
- 306 West 142 StreetManhattan D
- 470 Montgomery StreetBrooklyn D
- 147-04 72 AvenueQueens C
- 4149 Kings HighwayBrooklyn D
- 67 Macombs PlaceManhattan D
