This guide is general information, not medical advice. If you have health concerns, please consult a medical professional.
Common signs
A persistent musty or earthy odor, especially in closets, basements or bathrooms.
Staining, discoloration or bubbling paint on walls and ceilings; warped flooring or baseboards; condensation on windows; and a history of leaks, floods or roof problems.
Where to look in Bay Area homes
Crawlspaces and garages in hillside homes, bathrooms without exhaust fans, north-facing rooms in foggy neighborhoods, and areas below windows and skylights after winter storms.
Behind appliances with water lines — refrigerators, dishwashers and washing machines — is another common spot.
Common moisture hotspots in Bay Area homes
- 1Attic & roof deck
- 2Bathroom ceiling
- 3Windows & sills
- 4Under sinks
- 5Behind appliances
- 6Crawlspace / garage
A musty smell with no visible source is one of the best reasons to get a professional look.
AirCare 365 · Bay Area
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When to call a professional
If you notice an odor with no visible source, after water damage, before buying a home, or after a remodel, an inspection with moisture readings and sampling adds useful context.
Large areas of visible growth should be handled following EPA guidance, which recommends professional help for areas larger than about 10 square feet.
Want measured information about your home?
AirCare 365 provides mold inspection and mold and indoor air quality testing across the Bay Area.
Sources
Serving San Francisco, San Mateo, Menlo Park, San Jose, Sunnyvale, Palo Alto, Oakland, Fremont and the rest of the Bay Area.
Read next
- Mold Spores: What They Are, Where They Hide in Bay Area Homes, and How to Test for Them
- How to Test for Mold in Your House: DIY Kits vs Professional Testing
- How Much Does Mold Testing Cost in the Bay Area?
- Mold Inspection vs Mold Testing: What's the Difference?
Looking for a visit? Explore Bay Area mold testing.