Mold remediation
Fire & smoke cleanup
Storm response
Sewage cleanup
ReconstructionFree visual inspection and a written scope of work before any mitigation begins - photos, moisture readings, and drying logs go in your claim file
The scope we write is the scope we bill. Anything new gets shown to you, in writing, before we touch it.
Get your free estimateFast, Reliable Mold Remediation Across Yonkers
Mold remediation in Yonkers typically runs $1,800 – $6,500 depending on how far the colony has spread and what’s behind the wall. Most jobs in Park Hill, Nodine Hill, and the hillside blocks around McLean Avenue take two to five days from containment to clearance testing. We answer the phone live at (914) 233-3437 and can usually have a Threshold Verified technician at your door the same day you call. That matters here because Yonkers basements don’t dry out on their own.
We know this city’s housing stock. The pre-war brick walk-ups, the finished basements carved into hillside, the original galvanized supply lines that give out in February. Mold here doesn’t behave like mold in, say, Levittown. In Yonkers, it grows behind horsehair plaster, feeds on lime mortar, and travels through shared wall cavities between attached row houses. You need a crew that understands that before they cut into anything. Our Mold Remediation team works in Yonkers every week, not occasionally. We know the streets, the building types, and the failure modes.
Why Marsh Water Damage Yonkers Is Yonkers’s Preferred Mold Remediation Company
Since 2005, the Threshold Group family has handled water and mold jobs across Yonkers’s older neighborhoods. The work here is different. We’ve mapped moisture through lath-and-plaster walls in three-story walk-ups on Yonkers Avenue, contained active colonies in Park Hill row houses where the shared wall cavities link five units, and dried basement-corner pockets that stay at 70% relative humidity from hillside runoff. That’s not national-franchise experience. That’s Yonkers experience.
Every technician who shows up at your door is Threshold Verified. That means background-checked, identity-verified, uniformed, and sent to you by name and photo before the visit. They’ll show a photo ID badge at the door, every time. Tobias Reyner, who leads our Yonkers crews, built this standard because he knows how it feels to open your door to a stranger after something has already gone wrong in your home. You’ll know who’s coming. That’s a specific promise, printed on the work order.
We dispatch from our New York City office, but the crews working your job live and work in Yonkers and the surrounding Sound Shore towns. Response time to most Yonkers neighborhoods is under 90 minutes for emergency calls. And every job, no exceptions, gets a written price before work begins and a 365-Day Done Right Promise: if the repair isn’t right within a full year, we make it right, with a free second visit included automatically.
Restoration work we handle





Mold Removal Service in Yonkers
Mold Removal Service in Yonkers is the physical removal of active fungal growth from building materials and contents. In most Yonkers homes, this means cutting out affected drywall or plaster, HEPA-vacuuming exposed framing, sanding or wire-brushing structural wood, and applying an EPA-registered antimicrobial to the treated surfaces. A typical single-room job in a Yonkers apartment or rowhouse runs $1,800 – $3,200. Full basement remediations with finished-wall demolition and rebuild run $4,000 – $6,500.
HEPA Containment and Negative Air
Before any cutting starts, we seal the work area with 6-mil poly and run a negative air machine with HEPA filtration. This keeps dormant spores from traveling through the rest of your home. In attached Yonkers housing, this step is non-negotiable. Walking through a Park Hill rowhouse after demolition without containment can push spores into the neighbor’s unit through shared wall cavities. We don’t skip it.
Source Removal, Not Just Surface Cleaning
Wiping down visible mold with bleach doesn’t remove the colony when it’s rooted into porous materials. In Yonkers’s older homes, mold often colonizes the back side of plaster, inside wall cavities, and in the paper facing of drywall. Source removal means getting to the actual growth and removing the material it feeds on. If the masonry behind the plaster is wet, we map that moisture before we decide what to cut. More on that below.
Mold Remediation Services in Yonkers
Mold Remediation Services in Yonkers go beyond removal to address the conditions that let mold grow in the first place. That means structural drying, moisture mapping of masonry walls, humidity control, and air quality verification after the work is done. A full remediation package including containment, source removal, structural drying, and post-remediation verification in Yonkers typically runs $2,800 – $6,500, with basement jobs on the higher end because they almost always involve masonry moisture.
Moisture Mapping on Masonry Walls
In Yonkers’s hillside neighborhoods, the wall behind the mold is often brick or stone with lime mortar. That masonry holds water from freeze-thaw cycles, hillside runoff, and rising damp. We use moisture meters and thermal imaging to map where the water is in the wall, not just where the mold is on the surface. Treating visible mold without mapping the masonry behind it is the single most common reason mold returns in Yonkers basements.

Air Quality Restoration After Remediation
Once the source is removed and the structure is dry, we run HEPA air scrubbers and take post-remediation air samples to verify spore counts have dropped to normal background levels for Yonkers’s environment. You get the lab report. We don’t tell you it’s clean without data. That’s what Air Quality Restoration means in practice: the room is verified, not just visually inspected.

What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Yonkers
This matters more in Yonkers than most people realize: we run Dri-Eaz dehumidifiers, Phoenix axial air movers, and XPOWER air scrubbers on nearly every remediation job. These are the same machines used in commercial restoration, not rental-counter equipment. For Yonkers’s humid continental climate, where summers push ambient humidity above 70% and basements never fully dry on their own, running a commercial Phoenix dehumidifier means the difference between a five-day structural drying job and a two-week one. We keep replacement filters, HEPA bags, and spare parts stocked for these units, so if a machine goes down mid-job on a Nodine Hill walk-up, we swap it out the same day instead of waiting on a shipment.
See the difference
Before
After
Before
After
Before
AfterCommon Mold Remediation Problems We See in Yonkers Homes
- Mold returning after a surface cleaning. A homeowner wipes down visible mold on old plaster, it looks fine for six weeks, then it comes back. The colony was feeding on lime mortar and brick behind the plaster. We had a Park Hill basement where the visible mold was a three-foot patch on the wall, but the moisture map showed a seven-foot-wide wet band behind it from hillside runoff. You have to fix the masonry moisture, not just the surface growth.
- Shared wall cavities in row houses. In attached Park Hill and Nodine Hill housing, a mold colony in one unit can send dormant spores into the neighbor’s wall cavity during demolition. We’ve seen it happen. Containment has to go up before any cutting starts, and that’s not a default step in every company’s process. It’s a default in ours.
- Freeze-thaw pipe bursts upstairs, mold downstairs. A top-floor supply line gives out in January, the water travels down through two ceilings, and by the time anyone notices the stain, mold has already started in the basement. Yonkers’s pre-war walk-ups are built for this to happen. The water follows gravity, the old plaster wicks it into the walls, and the finished basement below becomes a petri dish.
- Dehumidification skipped during drying. Some companies set air movers and call it drying. In Yonkers basement-corner pockets that sit at 70%+ relative humidity from hillside runoff, air movement alone won’t hit the dry standard. You need a commercial dehumidifier pulling gallons of water out of the air daily. Without it, Category 2 water sits past the 48-hour mold clock and you’re doing remediation twice.
Our field crews hit this every week. Our techs took moisture readings behind a lath-and-plaster wall in a three-story Nodine Hill walk-up after a top-floor supply line froze and sent Category 2 water through two ceilings into a finished storefront basement. Antifungal containment went up within four hours, air movers and a Phoenix dehumidifier pulled structural drying logs below 17% moisture content in five days, and we removed only the wetted plaster keys instead of gutting the original 1923 horsehair plaster. That’s what local experience looks like on a Yonkers job.
Pricing for Mold Remediation in Yonkers, NY
Here are the real numbers for Yonkers’s market. A contained mold removal in a single room, including HEPA setup, source removal, and antimicrobial treatment, runs $1,800 – $3,200. A full basement remediation with masonry moisture mapping, dehumidification, and air quality verification runs $4,000 – $6,500. Crawl space treatment under a Yonkers home runs $1,200 – $2,800 depending on access and square footage. What pushes a job toward the high end: finished basements with drywall over masonry, multiple affected rooms, shared-wall row house containment, and Category 2 water from an upper-floor leak. Estimates are free, and the price is written down before any work starts. Call (914) 233-3437 and we’ll walk through what your specific job needs.
We Also Serve Cities Near Yonkers
Our crews work throughout southern Westchester, including Mold Remediation in Yonkers and the surrounding towns. We handle jobs in Bronxville, Tuckahoe, Eastchester, and Pelham regularly. Same Threshold Verified standard, same written pricing, same 365-Day Done Right Promise. If you’re in one of those towns and dealing with a basement that won’t dry or mold that won’t go away, call us at (914) 233-3437.
Serving Yonkers, NY - Our Local Coverage Area
We’re based in the Yonkers area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Mold Remediation in Yonkers
In most Yonkers basements, the mold is growing from moisture inside the masonry walls behind the visible surface, not from the surface itself. Yonkers’s hillside drainage and freeze-thaw cycles keep brick and stone foundations damp for six to ten months a year, so the colony has a constant water source that bleach and elbow grease can’t reach. Until that masonry moisture is mapped and dried, the mold will regrow. Call (914) 233-3437 and we’ll map the wall before recommending any removal.
Sometimes yes, sometimes no. If the plaster keys are intact and the mold is on the surface, we can often clean, treat, and seal the plaster without demo. If the colony is rooted behind the plaster into the lath and masonry, we have to remove the affected section. The original horsehair plaster in 1920s-era Park Hill buildings is worth preserving when it’s structurally sound, and we approach every job with that in mind. The written price before work starts will tell you exactly what’s coming out.
Mold can start in 24 to 48 hours when Category 2 water sits in warm indoor air. In a Yonkers walk-up with a top-floor leak, the water travels through ceilings and walls, wetting the back side of plaster and drywall where you can’t see it. By the time the stain shows on the ceiling below, the colony may already be active. That’s why emergency response matters: we’re typically at Yonkers addresses within 90 minutes and setting containment the same day.
Category 2 water is contaminated water, meaning it contains biological or chemical contaminants that can cause illness. A top-floor supply line leak that travels through two occupied floors picks up dust, debris, and bacteria on the way down, so the water that pools in your basement is not clean. Any porous materials it saturated are considered contaminated and should be removed or professionally cleaned. Our team handles this routinely in Nodine Hill’s three-story mixed-use buildings, and we’ll document everything for your insurance adjuster.
For a contained single-room remediation, most Yonkers homeowners stay in the home. The containment barrier and negative air pressure isolate the work area from living spaces. If the contamination is extensive, or if someone in the home has respiratory sensitivities, we’ll recommend temporary relocation and factor that into the plan. We’ll tell you before work starts, not after you discover a spore smell in the kitchen. Call (914) 233-3437 for a straight answer on your specific situation.
If you’re dealing with mold in a Yonkers home, don’t wait for it to spread through the wall cavities or into the masonry. Call Marsh Water Damage Yonkers at (914) 233-3437 for a free estimate. A live person answers, a Threshold Verified technician shows up, and the price is in writing before any work begins.
Written by Tobias Reyner, Owner at Marsh Water Damage Yonkers, serving Yonkers since 2005.