Said It Here

How to tell if mold is hiding after a roof leak

When water gets behind walls or under floors after a leak, invisible mold can trigger unexplained health symptoms like lingering coughs without any visible growth to confirm it. Professional inspections are prohibitively expensive and often viewed with skepticism, leaving homeowners paralyzed between the high cost of tearing up their house and the fear of ignoring a hidden hazard.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Using damp rid air freshener bags and dehumidifiers in the basement
  2. 2
    Running fans and checking humidity levels
  3. 3
    Checking the underside of the subfloor and joists from a crawlspace
  4. 4
    Having an inspector take air samples
  5. 5
    Hiring an independent mold testing company that does not sell remediation services to take baseline and indoor samples

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/Flooring1 person · September 2026

I’m worried that all that subfloor is moldy under my hardwoods and needs replacing but it would be a big decision to start ripping everything up when I don’t know.source ↗

Appropriate_Mess_532 · r/Flooring · 1 upvotes

I’m not sure it’s all from the bathroom, I’m worried about humidity in crawlspace, there is a moisture barrier under the house now but there wasn’t one for about 20 years before I moved in.source ↗

I’m not sure if that is sufficient or not with all the info about dangers of mold now.source ↗

Appropriate_Mess_532 · r/Flooring · 1 upvotes
r/HomeImprovement1 person · September 2026

My fiance has started getting a cough lasting for over 2 weeks. He is not sick. I’m terrified it’s a mold cough from mold, but I don’t see any visible mold.source ↗

I feel like getting a mold inspection would give me peace of mind, but I have heard they are scams. I also truly cannot afford it right now, but of course would get one if I needed to.source ↗

1812girl · r/HomeImprovement

Where this came up

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