Water damage drying
Fire & smoke cleanup
Mold remediation
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 Ontario
Mold remediation in Ontario, CA typically costs $1,800 to $6,500 depending on how far the colony has spread, and most jobs can be started within 24 to 48 hours of your call. We’re Whitfield Water Damage, and we run containment and drying crews throughout Ontario zip codes 91764, 91798, 91758, and 91761 on a weekly basis. If you’ve found mold after a roof leak, a water heater failure, or one of those Santa Ana wind events that peeled shingles off your roof, call (855) 382-0478 and we’ll have a certified technician at your door with moisture meters, HEPA air scrubbers, and a written scope before any work begins.

Why Whitfield Water Damage Is Ontario’s Preferred Mold Remediation Company
Ontario homeowners call us because we show up knowing what we’re looking at. A 1960s slab-foundation house on Grove Avenue behaves completely differently after water intrusion than a two-story home in a newer subdivision off Archibald. We’ve mapped enough moisture in Ontario’s older tract homes to know that water travels through wall cavities and under flooring in ways that have nothing to do with the visible stain on your ceiling. That local knowledge means we don’t seal up containment over an active colony hiding three feet away, and we don’t hand you a bill for surface cleaning when the framing underneath is still wet.
Our technicians are IICRC-certified, which means every mold remediation job in Ontario follows the same science-based protocol: contain, filter, remove, dry, treat. Whitfield Water Damage is also a member of the Restoration Industry Association and IFA, so our work holds up to adjuster scrutiny and industry peer review. When your insurance company asks for drying logs, moisture readings, and photo documentation, we hand them a file that looks like it came from a contractor who does this professionally, because it did.
Nolan Pruett leads our restoration team, and he’s built the company around one principle: a mold job is a drying job first. If you’re in Ontario and you’re staring at black staining on a bathroom ceiling or sniffing that musty smell from a closet wall, call (855) 382-0478. We’ll tell you what you’re actually dealing with, not what a sales script says you should buy.
Restoration work we handle






Mold Removal Service in Ontario
Mold Removal Service in Ontario addresses the visible colony now. This is what you need when mold has colonized a discrete area, the moisture source has been stopped or will be fixed during the job, and the structure around it is dry. A typical mold removal service in Ontario runs $800 to $2,500 for a contained area under 100 square feet, which covers most bathroom ceilings, closet walls, or a section of drywall behind a leaky window.
Surface and Cavity Removal
We remove mold from drywall, framing, and subfloor using HEPA-filtered equipment and antimicrobial treatment. In Ontario’s slab-foundation homes, mold often hides in wall cavities that look dry from the outside, so we run moisture readings before we close anything back up.
Antimicrobial Treatment
After physical removal, we apply antimicrobial treatment to the affected framing and adjacent surfaces. Ontario homes that go through a wet winter followed by a hot, dry summer can develop dormant spores that re-activate with the next rain, so we treat beyond the visible colony edge.
Mold Remediation Services in Ontario
Mold Remediation Services in Ontario go further than simple removal. This is the full protocol for homes where mold has spread into structural cavities, or where the moisture source is still active. In Ontario, that usually means a wind-damaged roof that’s been leaking into wall cavities, a slab foundation wicking ground water after winter storms, or an HVAC system that’s been circulating spores from a dirty attic. Full mold remediation in Ontario typically runs $3,000 to $6,500 depending on square footage and whether structural drying is required.
Containment and Air Filtration
Every full remediation job starts with containment barriers and HEPA air scrubbers running negative air. Ontario’s dusty attics after Santa Ana winds mean we change filters more often here, and we never run a drying setup without HEPA filtration in a home that’s already got airborne mold spores.

Cavity Drying and Structural Restoration
Using Injectidry systems, we dry wall cavities and subfloor spaces without tearing out every section of drywall. For Ontario’s slab-foundation homes with no crawlspace, this is the difference between a four-day drying job and a two-week demolition project.

What happens when you call
- 1
A real person answersNo phone trees — you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Ontario
We run Dri-Eaz dehumidifiers, Phoenix air movers, and XPOWER blowers on mold jobs across Ontario, and we keep replacement parts and filters stocked in our Victorville shop so we’re not waiting for a distributor when your job needs a HEPA filter swap. Injectidry cavity-drying equipment travels with us to every Ontario job because slab foundations here don’t give you a crawlspace to vent. When you see those brand names on the equipment in your hallway, you’re looking at the same machines used by the insurance-preferred restoration contractors in the Inland Empire.
See the difference
Before
After
Before
After
Before
AfterCommon Mold Remediation Problems We See in Ontario Homes
- Hidden mold in slab-foundation wall cavities. Ontario’s 1950s-to-70s tract homes have no crawlspace, so water that gets into a wall from a roof leak or window flashing migrates sideways through the wall cavity. Moisture mapping often finds the colony two to three feet beyond the visible stain.
- Santa Ana wind damage becomes a mold problem later. After a wind event peels shingles or cracks stucco, the damage looks like a roofing issue. But when winter rain arrives, water pours through those compromised sections into attic insulation and wall cavities, and by spring the mold is blooming behind the drywall.
- HVAC systems spreading spores from dusty attics. Ontario’s dry-season winds push fine grit into attic spaces and ductwork. When a mold colony takes hold in that environment, running an air mover without HEPA filtration just circulates spores through the living areas.
- Damp sill plates on slab foundations. Ontario’s winter rain wicks up through slab edges and keeps sill plates damp even when the visible drywall looks dry. Surface moisture readings can miss this, which is why we probe framing before we call a job done.
Pricing for Mold Remediation in Ontario, CA
Mold removal in Ontario for a contained area under 100 square feet runs $800 to $2,500. Full remediation with containment, cavity drying, and HVAC cleaning runs $3,000 to $6,500 on average. A crawl space treatment in an older Ontario home adds $1,200 to $2,800 depending on square footage and access. Three things drive cost here most: how far the moisture has migrated in a slab home, whether the HVAC system needs cleaning, and whether the roof repair that caused the leak has to happen before drying can finish. We give you a written scope before work starts, and our estimates are free. Call (855) 382-0478 for an exact quote on your Ontario property.
We Also Serve Cities Near Ontario
Our crews cover the Inland Empire corridor around Ontario, so if you manage a property in Montclair, Upland, Chino, or San Antonio Heights, we’re already working your area. The same IICRC-certified team that handles mold remediation in Ontario crosses city lines every week, and response times to those neighboring cities run about the same as our Ontario dispatch.
Serving Ontario, CA — Our Local Coverage Area
We’re based in the Ontario 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 Ontario
Mold can begin colonizing within 24 to 48 hours of water intrusion in an Ontario slab home, especially when the water is trapped in a wall cavity with no crawlspace ventilation. The warm air inside an Inland Empire home accelerates that timeline, which is why we treat every roof leak as a mold risk from day one.
After Santa Ana winds peel shingles or crack stucco on Ontario’s older tract homes, the damage leaves a direct path for winter rain to enter wall and attic cavities. The water gets trapped in those sealed slab-foundation spaces, and by the time rain season ends, mold has colonized the framing. We see clusters of calls in 91761 and 91762 every spring from exactly this sequence.
Moisture mapping means we take systematic moisture readings across floors, baseboards, and wall surfaces using pin and pinless meters, then map the readings to find how far water has actually traveled. In Ontario’s slab homes, that map regularly extends two to three feet past the visible stain, which tells us where to set containment and what needs to be opened up.
Yes. Every full mold remediation job in Ontario includes containment barriers and HEPA-filtered air scrubbing, not just air movement. That protects the rest of the house from cross-contamination and gives us a defensible air quality baseline for your insurance documentation.
Choose mold removal when the colony is contained, the moisture source is stopped, and the surrounding structure reads dry on a moisture meter. If the water has traveled into wall cavities or the HVAC system is involved, full remediation is the right call, and we’ll tell you which one you need before quoting anything. Call (855) 382-0478 and we’ll explain it in plain terms.
Written by Nolan Pruett, Owner at Whitfield Water Damage, serving Ontario since the company’s founding.