The framework.
The NYC Department of Housing Preservation and Development classifies housing maintenance code violations in three classes — A, B and C — based on the severity of the condition. The class determines both the time to correct and the time to certify correction.
Class A — non-hazardous.
Minor maintenance and cosmetic conditions. Examples: small cracks in plaster, peeling paint in non-friction areas without a child under six in the unit, minor floor damage.
Cure window: 90 days from issuance.
Certification: filed within 14 days of correction.
Class B — hazardous.
Conditions that impair safety, health or use. Examples: broken plumbing, defective stove or refrigerator, mold growth above defined thresholds, certain plaster and paint conditions.
Cure window: 30 days from issuance.
Certification: filed within 14 days of correction.
Class C — immediately hazardous.
Conditions presenting an immediate hazard. Examples: lack of heat or hot water (in season), lead-based paint hazards in apartments with a child under six, severe mold conditions, immediately hazardous structural defects.
Cure window: typically 21 days from issuance for most Class C violations; 24 hours for heat/hot water violations during heat season.
Certification: filed within 5 days of correction.
Lead and mold specifics.
Lead-based paint Class C: An HPD lead violation in an apartment with a child under six is a Class C violation. The 21-day window covers both the abatement work and the certification of correction — including the supporting clearance documentation.
Mold under LL55: Mold violations are classified Class B or C depending on the size and location of growth. LL55 violations carry their own certification requirements and an annual inspection regime layered over the violation process.
What "certification of correction" actually requires.
Certification is a signed statement by the owner (or an authorized agent) attesting that the violating condition has been corrected. For lead and mold violations, supporting documentation is also required:
- For lead: dust-wipe clearance results, inspector certifications, photographs.
- For mold: independent clearance report under NYS Article 32 (for projects above the threshold), photographs, work plan compliance.
HPD may inspect to verify before dismissing the violation. A certification submitted without supporting documentation — or with documentation that doesn't show the right thing — often comes back rejected.
What happens if you miss the window.
Open violations accumulate civil penalties (per-day, per-violation), affect property sales and refinances, and — for repeat patterns — can trigger more aggressive HPD intervention. Closing violations within their windows is materially less expensive than letting them age.