Possible Causes

• Swelling of wood due to seepage or penetration of rain, humidity and other forms of moisture into the home through uncaulked joints, deteriorated caulk, leaking roof or other areas
• Excess humidity or other moisture escaping from within the home through the exterior walls (less likely with acrylic paints, which allow water vapour to escape without affecting the paint film)
• Inadequate surface preparation
• Use of a lower quality paint that has inadequate adhesion and flexibility characteristics
• Applying acrylic paint under conditions that hinder good film formation, e.g., on a very hot or cold day; in windy weather
• Applying an oil-based paint over a damp or wet surface.

             Solution

            If exterior moisture is the cause, eliminate the source by
            doing necessary repairs and maintenance:

• Replace caulking;
• Repair roof;
• Clean gutters and downspouts;
• Cut heavy vegetation away from the building.

If moist air is originating from inside, consider installing vents (especially in rooms that tend to get humid such as the kitchen, bathroom and laundry room); attic louvres, exhaust fans and dehumidifiers may also help. Remove all loose paint with a scraper or wire brush, sand rough surfaces and prime any bare wood. Repaint with an ultra premium quality acrylic paint
- it will provide excellent adhesion and allow water vapour to escape without harming the coating.

This information is provided by the Rohm & Haas Paint Quality Institute, www.paintquality.com.au