Peeling paint can be due to any of three common causes, including lack of surface preparation, moist walls and wrong paint, according to Red Beacon. If the wall underneath is dirty, wet or covered in old paint, the paint on top of the bad layer may not hold properly. One way to fix peeling paint is to paint the wall correctly after scraping off the malfunctioning layers.
For surface preparation, a clean surface is necessary followed by a coat of primer, advises Home Guides. Thoroughly wash the walls with water and soap. Vacuum the wall to clean up any dust and dirt. Primer makes paint colors hold properly to the wall and creates a smooth surface.
Paint doesn't dry or adhere properly if the surface is wet or damp. Moisture weakens the adhesive properties of paint and primer, so exterior walls should always be painted in sunny, dry weather. Oil-based paints do not adhere when moisture is on the wall because oil and water do not mix.
Using the wrong paint on a surface also can yield peeling paint. One solution is to completely remove dry paint. Another way around a paint layer is to find the right primer to cover over the old paint before adding a fresh coat.