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.
Found another way around this?
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How to tell if mold is hiding after a roof leak
- 1Using damp rid air freshener bags and dehumidifiers in the basementDid this help you?
- 2Running fans and checking humidity levelsDid this help you?
- 3Checking the underside of the subfloor and joists from a crawlspaceDid this help you?
- 4Having an inspector take air samplesDid this help you?
- 5Hiring an independent mold testing company that does not sell remediation services to take baseline and indoor samplesDid this help you?
- 6trying to smell the affected area up closeDid this help you?
- 7analyzing the precise pattern of discoloration on rafters versus sheathingDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Landlord came by to remove the panel and insulation, and he’s telling me he doesn’t see any mold, and that the wood is “just wet.” Is he BSing me”source ↗
“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 ↗
“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 ↗
“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 ↗
Where this came up
People with this problem also raised
- 3Is this mold or a water leak, and do I need to call someone?
- 8How to find and handle hidden mold behind walls
- 26How to clean mold on furniture after rain gets inside
- 2Roof or gutter contractors missed rotting fascia board
- 2What to do about mold in an apartment HVAC system
- 8Is the black stuff in my air conditioner mold or dust?