Key points
- Run the fan during the shower and for a while after — many guides suggest about 20 minutes.
- It must vent outside, not into the attic.
- Test it — a tissue should be pulled against the grille.
- A timer switch makes it automatic.
Signs it isn’t working
- Mirror stays fogged long after showering
- Mold spots on the ceiling or above the shower
- Peeling paint
- Dust-clogged grille or loud, weak fan
The attic problem
Fans vented into the attic dump warm, wet air onto the roof sheathing. In Utah winters that can lead to frost, dripping, and mold on the underside of the roof — see attic mold.
What to do about existing mold
Small surface spots can be cleaned — see small mold cleanup. Recurring or large growth may mean a hidden leak — see shower pan leaks.
Bathroom mold coming back?
Call (385) 250-2825 — answered live 24/7 by the Vault crew.
Mold remediation services · Mold in bathroom · Condensation and mold
Found mold in a Provo home? Start with a mold inspection, then see how we handle mold remediation in Provo. Call (385) 250-2825.
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