Bubbles resulting from localized loss of adhesion and lifting of the paint film from the underlying surface.
Possible Causes:
- Painting a warm surface in direct sunlight.
- Application of oil- base or alkyd paint over a damp or wet surface.
- Moisture escaping through the exterior walls.
- Exposure of latex paint film to dew, high humidity or rain shortly after paint has dried, especially if there was inadequate surface preparation.
- If blisters go down to substrate, try to remove the source of moisture.
- Repair loose caulking; consider installing an exhaust fan.
- If blisters do not go all the way down to the substrate, remove them by scraping, sanding; prime bare wood and repaint.