9. Peeling Exterior Paint "The main cause of paint failure is inadequate prep work," says Doug Hanhner, team leader/supervisor of the Benjamin Moore Paints Product Information Center in Flanders, New Jersey. Glossy surfaces must be sanded; otherwise your new paint will start coming off in sheets with the first major change in temperature. Another common problem is moisture getting behind paint and working through the surface. After power washing your house, allow at least 14 days for the siding and sheathing to dry before painting. Occasionally, moisture escaping through walls (especially in the kitchen and baths) can cause paint to peel. Painting too early in spring or too late in fall can also cause paint to fail prematurely. Even though it may feel dry to the touch in a day or two, latex paint needs to remain above 50 degrees F for at least 14 days in order to cure properly. To deal with peeled paint, scrape down to a solid base (preferably bare wood), and apply an alkyd primer. Alkyds penetrate deeper and adhere better than latex primer. "Latex primers breathe better, but alkyds prevent moisture from getting trapped between the primer and base, which can also lead to paint failure," explains Hanhner. Apply two topcoats to build up a sufficiently thick skin. When rolling or spraying, you should also "back brush" to help "seat" the paint, which creates a stronger mechanical bond with the surface.