How To: Refinishing Vinyl Siding
Vinyl siding is made from vinyl plastic and pigments. There is no coating. The pigments are distributed all though the plastic. After years of exposure to the elements, fading, chalking, and dirt pick-up diminish the appearance.
Vinyl siding is a good substrate to paint since it is relatively dimensionally stable and doesn’t crack like wood surfaces do. With care in surface preparation, selection of primer(for metal parts) and topcoat, and good application, a repaint job’s longevity can approach the life of the original siding.
Vinyl siding will warp from heat build-up. For this reason, very dark colors are not recommended. As a general rule, do not paint vinyl siding any darker than the color of the original vinyl siding color.
The surface must be clean. There are four things that usually must be eliminated before priming can occur: dirt, grease and grime, mildew and chalk. Rust may be present on metal fasteners, flashing, etc. Rust must be removed by brushing with a steel brush. A power wash will normally, but not always, remove dirt and chalk. Usually, plain water will do the job. If cleaners or bleach is used in the wash, the chemicals must be rinsed off before priming. After power washing, the surface should be rubbed with a black cloth. If there is evidence of chalk on the rag, the remaining chalk must be abraded off by scrubbing with a brush followed by a rinse. Paint will not stick to a chalky surface. A chlorine containing chemical such as household bleach will remove mildew. If bleach is used, it must be rinsed off before priming.
Priming of the vinyl siding is not necessary. Prime metal parts with Z6631 Krylon Iron Guard after cleaning and removing the rust.
After the primer is thoroughly dry, apply a coat of California Aqua Borne Ceramic House Paint if a semi-gloss finish is desired. Apply a brush, roller or spray. Thin sparingly with water as needed. Do not apply under 50 degrees. Use a .017 to .021 tip for airless spray applications. Both finishes dry to a hard, impervious finish that resists dirt pickup and is non-chalking. One coat will give good protection, but two coats are recommended for the best durability. Allow the first coat to dry thoroughly before recoating. At least two hours under normal conditions is needed before recoating.