Water sitting on windowsills will eventually penetrate a paint film through cracks and openings in the coating.
Remedy:
- Remove all loose paint by scraping.
- Feather all rough edges with sandpaper.
- Remove old glazing and reglaze.
- Caulk joints at a 45-degree angle.
- Spot-prime with exterior primer.
- Use oil-based gloss paints for surfaces exposed to standing rain and snow.
- Leave a 1/16″ edge of paint on the pane of the window to prevent water from getting behind the paint film.
- Use of storm windows helps prevent peeling from recurring.