Mold Remediation in NYC

New York licenses mold work under Labor Law Article 32. The Department of Labor's mold program FAQ defines a mold project as assessment, remediation or abatement of an area larger than ten square feet, and says an area under ten square feet may be cleaned up on your own. Above that line the law requires two separate licensed parties: a mold assessor who inspects and writes a remediation plan, and a remediation contractor who does the work from that plan. The same individual may not assess and remediate the same property, and it has been unlawful since January 2016 to advertise mold services without a license. Home inspectors who assess mold need the assessor license too.

New York City Adds a Building-Size Rule

Two 2018 city laws layer on top. Local Law 55, the Asthma-Free Housing Act, requires the owner of a building with three or more apartments to inspect every occupied unit and the common areas for mold, mice, rats and roaches at least once a year and to use approved work methods. Local Law 61 requires owners of buildings with ten or more apartments to hire outside licensed assessors and remediators for every mold project over ten square feet, whether or not HPD has issued a violation, and the contractors file their reports with the city. The Health Department's mold page states the landlord's underlying duty plainly: keep tenants' homes free of mold, including safely repairing the water leaks behind it.

Checking a License

Both lists are public on the state's open data portal: licensed mold contractors and licensed individuals. Search the company and the named assessor before you sign anything.

There is no reliable NYC price survey for mold work, and the figures that circulate online are marketing pages that disagree with one another. One cost site's 2022 estimate for New York put remediation at $17 to $34 per square foot, which prices a 500-square-foot job at $8,400 to $16,800; one contractor's own page claims $1,000 to $5,000 for an average city job. The most useful anchor is the city's actual spending: HPD's fiscal 2025 indoor allergen report records 650 emergency mold repair orders at an average of $2,089 per apartment, and those are jobs where the owner failed to act and the city sent its contractor in. A typical apartment bathroom or bedroom wall lands in that area; a full apartment after a flood costs multiples of it.

Where the Money Goes

• Assessment and plan. A separate fee for the licensed assessor's inspection and written remediation plan, then another visit for the clearance inspection at the end.
• Containment and removal. Plastic containment, negative air, removal and disposal of affected drywall or plaster, and HEPA cleaning of the area.
• Rebuilding. New drywall, taping, priming and paint are usually quoted separately from the remediation.
• The leak. Fixing the pipe, roof or window that caused the mold. Without it the mold comes back and the clearance report is worthless.

Be wary of sampling sold as a necessity. The Department of Labor's own guidance says sampling will almost always reveal mold or mold spores and that there are no national or state standards to compare the results against; a visible problem needs a plan, not a lab bill.

In a rental the landlord pays. Mold is a housing code violation, and HPD grades it by size: under ten square feet in a room is Class A with 90 days to correct, ten to twenty-nine square feet is Class B with 30 days, and thirty square feet or more in a room is Class C, immediately hazardous, with 21 days. HPD upgrades uncorrected Class A to B and B to C, reinspects every B and C mold violation, and does the emergency repair itself on Class C when the owner does not. Mold violations cannot be certified as corrected online; the owner has to prove the work. HPD issued 41,345 mold violations in fiscal 2025, a third of them upgrades of violations the owner had let sit.

Getting It Fixed

Report the mold and the leak to the landlord in writing. If nothing happens, file a 311 complaint, and if there is a child with asthma in the apartment ask 311 for the Healthy Neighborhoods Program, which sends a health inspector. A building's violation record shows whether mold and leak complaints are already on file, and our guides on who pays for mold removal, when mold makes an apartment uninhabitable and finding hidden mold cover the tenant side. Owners who need to clear a violation on the clock can start with clearing an HPD mold violation.

The sequence is fixed by the state's guidance for hiring mold professionals. The assessor inspects and writes a remediation plan. The remediation contractor turns that into a work plan, gives it to the owner before starting, builds containment and does the removal. The assessor then comes back for a post-remediation inspection, and the project is complete only when the assessor issues a written passed clearance report. The contractor may not remove materials or take down containment until that report exists, so a contractor who offers to assess, remediate and sign off in one visit is offering something the law does not allow.

Before You Request a Quote

• Photograph the mold with something for scale, so the assessor can tell whether the job crosses the ten-square-foot line.
• Say where the water came from, if you know: a leak from above, a window, a pipe, condensation. The fix for the source is part of the job.
• State whether you rent or own and whether the landlord has been notified in writing.
• Mention anyone in the apartment with asthma or a respiratory condition, which changes the containment and scheduling.
• Ask the company whether the assessor and the remediator are separate licensed parties, and get both license numbers.
• Ask whether rebuilding the wall or ceiling is in the quote or separate.

Expect two to three weeks from assessment to clearance for a typical apartment job, longer if the leak repair involves the building's plumbing or roof and another contractor.