When Wood is Dry
Sherwin-Williams suggests that you wait until the treated wood is thoroughly dry and then paint it. The company recommends painting as soon as the wood will accept a finish, explaining that waiting too long will cause the wood to deteriorate because of lack of proper protection.
At Least 90 Days
While Sherwin-Williams recommends painting or staining a treated deck as soon as the wood dries, Scott Paints claims that you should wait at least 90 days and preferably six months before painting. The company says that this will allow excess chemicals to drain from the wood, allowing the paint to stick better.
While opinions vary on proper waiting time, Southern Pine By Design proposes a safe method. Southern Pine advises painters to check with the manufacturer of the paint or stain for a recommendation on how long to wait before applying its product to pressure-treated wood.