Painting Preparation: Prime and Paint According to the Surface Location
1. New unpainted wood
Prime with high-quality acrylic latex or oil-base exterior wood primer. Use a stain-blocking primer for woods like cedar and redwood whose tannins will bleed through the finish coat.
2. Weathered unpainted wood
Sand weathered wood to renew the surface for better adhesion. Prime as new unpainted wood.
3. Previously painted wood
Primer is usually not necessary unless the paint chalks heavily or is peeled to bare wood. However, even a sound surface can benefit from a high-quality primer, which will provide maximum adhesion, uniformity, and mildew resistance.
4. Stucco and other masonry
On new and porous surfaces, apply masonry primer. Over old paint, spot prime only where paint is removed to the substrate during surface preparation.
5. Ferrous metals
Wire-brush rusted areas on pipes or other steel or iron. Then wash, rinse, and let dry. Apply acrylic latex or oil-base rust-inhibitive primer before painting.
6. Aluminum, galvanized iron
Remove oxidation with a synthetic scrub pad and wash the surface. Apply metal primer to all bare metal.
7. High-humidity areas
Use high-adhesion interior primer on walls and ceilings in humid rooms, such as bathrooms, kitchens, and laundries.
8. Slick, glossy surfaces
For maximum adhesion, sand the surface first with fine (220-grit) aluminum oxide sandpaper. Use bonding primer on glass, ceramic tile, and plastic laminates. (But do not paint countertops.)
9. Unpainted drywall
Prime unpainted drywall with latex drywall primer, then finish coat with latex wall paint. (If stains are present, use a stain-blocking primer.)
10. Stained walls
Clean the surface. Apply stain-blocking primer on walls with stubborn dirt, ink and crayon marks, smoke residue, grease, or water stains.
11. Semigloss or gloss paint
Prime with enamel undercoater to ensure the paint will attain its maximum gloss. Some enamel undercoaters call for light sanding after application.