Remove loose or peeling paint, mildew, dirt, oil, wax, and other surface contaminants by power washing or sanding. Treat mildew with a bleach solution, and rinse thoroughly before painting. Fill all nail holes and other surface defects with a proper filler or caulk. All butt joints must be caulked after primer coat to prevent moisture from attacking the open-end grain. Old glossy finishes should be sanded to a dull finish, dusted, and spot primed prior to painting.
Bleeding woods such as cedar and redwood will stain light color made in latex paints or latex stains. To avoid this, #160 Primer or an oil stain system should be used.
Knotholes should be sealed with one or two coats of shellac prior to priming.
All primers should be brush or roller applied on raw wood. Back rolling is essential when spraying primer on new wood.