Gateway/Services/Mold remediation

Mold remediation
in St. Louis.

Most mold gets over-diagnosed and over-remediated. We do the opposite: test the air and the surface, write the scope from the data, and only remove what the readings say has to come out. Honest scope, real plans.

Gateway technician taking an air-quality sample on a damp basement wall with visible mold staining.

What’s actually happening

Mold isn’t always mold.
That’s the whole problem.

The thing on your wall might be active mold. It might also be mineral residue from years of dampness, soap scum from a basement utility sink, or a biological staining that’s already dead. Without testing, even an experienced eye can’t tell. Without testing, every remediation scope is a guess.

Type 1

Surface staining

Cosmetic discoloration that looks like mold but isn’t. Mineral residue, smoke, soap scum, or dead biological staining. Doesn’t need remediation, but does need an honest answer.

Type 2

Active growth

Living mold colonies releasing spores. Usually visible as fuzzy or velvety, often with detectable odor. Real remediation work: containment plastic, HEPA negative-air, removal, antimicrobial.

Type 3

Hidden colonies

Mold growing behind drywall, in HVAC ducts, in ceiling cavities. Often discovered by smell or during demo of a different scope. Air-quality testing usually catches it before tear-out.

“We won’t tell you it’s mold because it looks like mold. We test, we plan, and we tell you what you don’t need to remediate.”

The Gateway approach

What’s included

Every Gateway mold job
covers all of this.

  • Air-quality testing

    Spore counts on the affected area + an outdoor control sample. The control matters, a high indoor count only means something compared to ambient outdoor.

  • Surface sampling

    Tape lift or swab where indicated. Identifies genus and rules out non-mold staining. Lab turnaround typically 2–3 business days.

  • Moisture-source diagnosis

    Mold is a moisture problem. We trace the water source, leak, condensation, infiltration, vapor, and document it for the remediation plan and for any reconstruction.

  • Containment + negative air

    Polyethylene containment of the work area. HEPA-filtered negative-air machines so spore-laden air doesn’t migrate to the rest of the home during removal.

  • PPE-required removal

    Full PPE (P100 respirators, Tyvek, gloves). Affected materials cut, bagged, and disposed of inside containment. No spore release into clean spaces.

  • HEPA cleaning + antimicrobial

    Surface HEPA vacuum and damp-wipe of every surface inside containment. Antimicrobial applied where it’ll do something, never as performance theater.

  • Clearance air-quality test

    Independent post-remediation testing to confirm spore counts have returned to (or below) baseline. We don’t take down containment until the numbers say we can.

  • Final report + photos

    Pre, during, and post photos. Lab results. Scope-of-work executed. Clearance test results. The complete file, for you, for insurance, for any future buyer of the home.

How a mold job runs

Four steps. Same every job.

  1. 01

    Inspection & testing.

    Visual assessment, moisture mapping, air-quality samples, surface samples where indicated. Lab turnaround drives the plan.

  2. 02

    Scope & approval.

    Written remediation scope based on the lab results. We walk you through it before any demo. You approve, then we mobilize.

  3. 03

    Containment + removal.

    Containment built. Negative air running. Affected materials removed by PPE-equipped crew. HEPA cleaning of all interior surfaces.

  4. 04

    Clearance + close-out.

    Independent clearance air-quality test. Once it passes, containment comes down, final cleaning, full documentation file delivered.

Insurance & mold

Mold coverage is its own thing.
We help you read it.

Most homeowners policies have a mold cap, often $5,000 or $10,000, that’s separate from the underlying water-damage coverage. Whether mold remediation is covered at all depends on the source: sudden water event with prompt mitigation usually yes, slow leak ignored for months usually no.

We’re trained to document the source and the timeline so the carrier has what they need to make a decision quickly. We’ll tell you upfront what’s likely covered and what’s not, including when it’s worth fighting and when it isn’t.

  • Source-of-moisture documentation built into every job
  • Pre and post air-quality testing for the file
  • Photo + scope documentation aligned to carrier expectations
  • Direct adjuster communication when you authorize it
Talk to us about your claim

Common questions

What homeowners ask
before they book the test.

Do I really need a test, or can you just look at it?

If the affected area is small (under a few square feet), the source is obvious, and visible growth is clearly active, sometimes a visual is enough. For anything larger, anything ambiguous, anything with a health concern, or anything where the homeowner wants documentation, we test. The cost of testing is small compared to the cost of remediating something that wasn’t actually a problem.

How much does a mold inspection cost?

A residential air-quality inspection with a control sample and one affected-area sample typically runs $375–$550 depending on home size and number of sample points. Surface samples (tape lift or swab) are $75–$125 per sample. We give a fixed quote upfront, no surprises.

When can I move back into the room after remediation?

Usually within 24 hours of clearance, once the post-remediation air-quality test passes and the containment comes down. For pregnant women, infants, or anyone with severe respiratory conditions, we’d suggest waiting a full 48 hours after final cleaning.

Will my insurance cover this?

Maybe. Most policies cap mold coverage at a flat amount (commonly $5K–$10K) and require the source to be a covered peril. If the mold was caused by a sudden water event you mitigated promptly, coverage is more likely. If it grew from a slow leak you knew about, less likely. We help you read the relevant policy language.

Is black mold actually dangerous?

“Black mold” is a common name for Stachybotrys chartarum, which is one of many mold species. It’s not the only species that matters, and color alone isn’t a reliable identifier. Health impact depends on the species, the spore count, and the individual’s sensitivity. We let the lab tell us, not the color.

Why do you do clearance testing? Other companies don’t.

Because “trust me, it’s gone” isn’t documentation. Independent clearance testing is the difference between hoping the work was complete and proving it. It also matters when you sell the home, a documented clearance is a real asset on the disclosure.

Suspect mold? Don’t guess.

Schedule an inspection. Live phone, twenty-four seven.

Call (314) 555-0123