Mold & Mildew
Musty smell without visible mold
Likely cause, what to safely try first, and whether it gets worse if you wait.
Likely cause
Hidden mold growth behind a wall or under flooring, often from a slow leak.
What to try first
- Check for any hidden moisture sources nearby (behind appliances, under sinks, basement corners).
- A musty smell with no visible source is worth a professional inspection, not just air freshener.
⚠ This tends to get worse (and more expensive) the longer it's left unaddressed — worth acting on soon.
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