Update for 2019: How Dry Does the Deck Need to be After Cleaning it to Apply the Stain?
Since we published this article, the Restore-A-Deck Wood Stain was introduced, allowing for this stain to be applied to a damp deck. For all other brands of stain, we still recommend you wait until the surface has completely dried before applying. We always appreciate your input, so feel free to leave a comment below with pictures of your deck stain projects.
The first step in deck restoration and/or maintenance is to clean and prep the wood. This is the key to a long-lasting finish. Properly prepped wood will allow the deck stain to penetrate and perform to its full potential. So how dry does the deck need to be after cleaning it to apply the stain? Well, that can be measured in several ways.
One way to measure if the deck is dry enough for staining is by using a moisture meter. A moisture meter measures the amount of moisture in the wood. There are one to two probes on the meter that stick into the wood to give you a reading. If using this method, be sure to check the moisture level in several spots. For example, the decking floor may be much dryer from the sun beating on it than one of the spindles hidden in the shade. With a moisture meter, you are looking for a reading between 12-15% or less. If you are getting higher readings then the deck needs to air dry some more before applying the stain.
Another way to be sure a deck is dry enough to stain is to give it a few days. Normally 1-2 days after cleaning is adequate but that can vary depending on sun exposure, climate, wood type, and age. To be more than safe you can let the deck dry for several days. The only problem you may have is that it may rain in those several days and if it does then you have to give the deck several more days again after it quits raining.
Allowing a deck to dry enough and then having it rain on the day you were supposed to stain can be frustrating. But consider this, if you do not let the deck dry sufficiently prior to staining, you can actually trap moisture in the wood underneath the new coat of stain. Then the wood is prone to mold and mildew problems, which can lead to rot and decay. So it is best to play the waiting game and allow the deck to dry long enough before staining.