CAUSES: All color pigments will fade after prolonged exposure to ultraviolet light, but certain conditions speed up the process. Using a colorant designed for interior use on an exterior surface causes more rapid fading. The use of a tinting base made with chalking-type pigments to make an exterior color also encourages the problem.
Moisture behind the paint film can eventually leach pigment from the film. Alkali burns on masonry surfaces can contribute to fading.
SOLUTIONS: Once color has faded, the only solution is to repaint. Latex finishes are generally better than oil or alkyds for color retention. Use colorants formulated for exterior use only, which your local independent dealer can recommend. Correct any possible sources of moisture such as cracked caulking or clogged gutters and downspouts.
On unpainted masonry, use an alkali-resistant primer appropriate for the type of finish coat intended. On burnt surfaces, scrape away as much of the paint as possible and spot prime the bare spots with an alkali-resistant latex primer. Apply a full coat of primer after this and finish with a latex masonry paint finish coat.
Acrylic paints have proven to be excellent products for tint retention.
