Bathrooms
- Soft flooring near the toilet or tub
- Grout or caulk that fails repeatedly in the same place
- Loose tile or hollow sound when tapped
- Peeling paint on the ceiling below
- Persistent musty smell
- Fan that doesn't clear steam
Kitchens
- Swollen or delaminated cabinet base under the sink
- Discoloration at the dishwasher or refrigerator line
- Warped flooring adjacent to appliances
- Slow, intermittent drips that dry between uses
Elsewhere in the house
- Stains that reappear after being painted over
- Baseboard separating from the wall
- Sticking doors in one area of the house
- Odor concentrated in one closet or corner
Why painting over it doesn't work
A stain is the record of moisture, not the moisture itself. Painting removes the record. If the source is still active, the stain returns — and in the meantime, the material behind it continues to degrade.
What to do when you find it
Photograph it, find the source before repairing the symptom, and get the affected material dried or removed rather than sealed in. Repair scope should be defined after the source is identified, not before.
What to take away
- Repeated grout and caulk failure is a construction symptom, not a maintenance one.
- Stains that return after painting mean the source is active.
- Find the source before pricing the repair.