What Are the Issues with Dark Paint on Composite Outdoor Trim?

Fades

• A dark-color composite outdoor trim can fade. B&B Wood Products, a manufacturer of composite materials, says to avoid using dark colors for painting surfaces that are consistently exposed to direct sunlight. Over time, sunlight can cause the paint to discolor.

Buckles

• Dark paint on composite outdoor trim and other outdoor surfaces is exposed to extreme heat due to direct sunlight. According to Modern Machine Shop, a home maintenance website, applying certain brands of exterior paint to light-colored composite outdoor trim made of PVC and other synthetic materials causes them to buckle. Composite materials painted dark colors retain more heat than materials painted in lighter colors. As a result, dark colors tend to melt composite trim when it's exposed to sunlight. Sherman-Williams, a national paint manufacturer, acknowledged this problem and developed an exterior line of paint called VinylSafe that is especially formulated for composite materials. The line features several dark colors that are safe to use on outdoor composite trim.

Peels

• All materials, including composite ones, require that you prepare the surface prior to painting; otherwise, the paint may not properly adhere to the surface and peel. Peeling is especially noticeable with dark paints because, as the paint peels, the light-colored composite material underneath is revealed, diminishing the trim's appearance. Make sure that the trim is clean and dry before painting. Paint the trim with a primer, which helps create a better bond between the paint and the composite trim. Thoroughly mix the paint before applying it to the surface to ensure that it provides a consistent color and coats evenly.