Symptoms
- Small black, gray, or brown spots on the ceiling above or near the shower
- Spots that seem to spread slowly over weeks or months
- Musty smell in the bathroom
Likely causes
- CommonInsufficient bathroom ventilationSteam from showers that isn't vented out condenses on the ceiling and feeds mold growth.
- CommonExhaust fan not working or not used often enoughA weak, broken, or rarely-used fan lets humidity linger long after a shower.
- PossibleRoof or plumbing leak above the ceilingA leak feeding consistent moisture, rather than just shower steam, can cause a similar but often larger mold patch.
What to do
- Check that the exhaust fan is working by holding a tissue near it; it should be pulled toward the vent.
- Run the exhaust fan during every shower and for at least 15–20 minutes after to clear humidity.
- Clean small mold spots with a bathroom-safe mold cleaner or a mild bleach solution, following product directions and ventilating the room.
- Check for a soft spot or larger stain that might indicate a leak from above rather than just condensation.
- Have the exhaust fan repaired or replaced if it isn't pulling air, and confirm it vents to the outside, not just into the attic.
- Consider a mold-resistant bathroom ceiling paint after cleaning to help prevent regrowth.
- Address any confirmed roof or plumbing leak found above the ceiling before repainting.
Tools and parts
- Spray bottle
- Scrub brush or sponge
- Gloves
Mold and mildew cleanerSearch: “bathroom mold mildew cleaner”
Mold-resistant ceiling paintSearch: “mold resistant bathroom paint”
When to call a pro
Call an electrician or handyman to repair or replace a non-working exhaust fan, and a roofer or plumber if a leak is found.
Safety
Use caution
Wear gloves and ventilate the room when using bleach or mold cleaners, and never mix bleach with ammonia-based products.