Pro Tips for Exterior House Painting
Treat any mildew with a household bleach mixture then rinse thoroughly. Use detergent and water to remove any loose dirt or sand.
Priming—Prime all areas where the old paint has come off. For best results, prime the entire job using quality exterior stain-blocking latex or oil-based wood primer. Use quality oil-based primer and paint if the surface has a buildup of old oil-based paint.
Painting—Use top-of-the-line exterior 100-percent acrylic latex house paint in flat, satin, semigloss or gloss finish, depending on desired appearance. A flat finish will provide a more uniform appearance, but quality satin and semigloss finishes will resist mildew more than a flat. Do not apply oil-based paint over latex-based paint or stain.
Surface prep—Treat any mildew with a bleach solution. Clean off any dirt or chalk with detergent and water, or power-wash, then rinse thoroughly.
Priming—Priming generally is not necessary if mildew, dirt and chalk are all removed as part of surface preparation.
Painting—Use top-of-the-line exterior 100-percent acrylic latex house paint in flat or satin finish. A flat finish will be much less revealing of variations and irregularities in the siding than will a glossier finish. For vinyl siding, apply only very light color paint: white, off-white or a light pastel. A rule of thumb is to not paint the vinyl siding any darker than its original color. Applying a darker color may cause irreversible warping (called “oil canning”) of the vinyl siding, due to the heat absorbed from sunshine by darker colors. For best results, apply the paint with a sprayer.
Surface prep—Treat any mildew with bleach then remove dirt, chalk, treated mildew, etc. by scrubbing with detergent and water, and rinse thoroughly. Chalking on weathered aluminum siding tends to be deep in the factory finish, and a second treatment may be necessary if there is still noticeable chalk on the surface.
Priming—Priming is generally not necessary if chalk can be removed as part of surface preparation. For areas where chalk is stubborn and cannot all be removed, apply a solvent-based exterior primer recommended for aluminum siding.
Painting—Use a sprayer to apply top-of-the-line exterior 100-percent acrylic latex house paint in flat or satin finish. A flat finish will be much less revealing of dents and irregularities. Note that because excess chalk can hinder the adhesion of paint to aluminum siding, some manufacturers offer acrylic latex additives that help exterior latex paint stick to hard-to-coat surfaces. For excessively chalky surfaces, consider using a product such as EmulsaBond from Flood Paint Solutions.
Editor’s Note: Much of the information from this article came from the Paint Quality Institute. Learn more at www.paintquality.com.
Side Note 1
Painting with a Sprayer
When applying paint with a sprayer, either HVLP or airless, movement of the gun is extremely important. Keep your wrist straight and the spray nozzle parallel to the work surface for consistent application (rather than flexing your wrist and swinging the gun, which causes overspray and uneven coating). The gun should be held 7 to 12 inches away from the work surface. Start at the top and work downward. To avoid excessive paint accumulation, don’t pull the trigger unless the gun is in motion. Squeeze the trigger as you move into a spraying pass over the work surface. Follow the tool manufacturer’s guidelines for tip selection and paint-thinning recommendations.