- Applying oil-based or alkyd paint over a damp or wet surface.
- Moisture seeping into the home through the exterior walls (less likely with latex paint).
- Exposure of latex paint film to high humidity or moisture shortly after paint has dried, especially if there was inadequate surface preparation.
- If blisters do not go all the way down to the substrate: Remove blisters by scraping, and sanding, and repaint with a quality acrylic latex interior paint. If blisters go down to the substrate: Remove the source of moisture, if possible. Repair loose caulking; consider installing vents or exhaust fans. Remove blisters as above, remembering to prime before applying the top coat.