Unless it rains a lot, you should wash your sign with a hose and cold water once or twice a year.For HDU signs, the paint should retain itscolor and brightness for five years. After that, minor fasing may occur if the sign's face is in the sun, but the basic color should be good for 10 years. We put two coats of 1-SHOT Oil enamel to provide long-life with minimal fading. After 5 years,if you wish , you may wish to retouch fonts with any oil enamel with matching color.