First, you must be sure that your deck has completely dried from the washing process. This will take at least 24 hours.
Next inspect the deck for raised fibers, and use sandpaper to smooth any out that you find. Decks that are very old may require more extensive sanding. If this is the case, you will want a power sander to do the job. There is a variety of sanding equipment available. For an amateur homeowner, palm and vibratory sanders may be the best choice because they pose the least risk for doing damage. A disc or belt sander will cover more area quickly, but can damage the wood if not used carefully.
Before moving on to staining and sealing, you may want to take the additional step of using a brightener. Though there is an extra cost, a brightener can restore the appearance of old, weathered wood. If you choose to use a brightener, be sure to rinse thoroughly afterward, and again allow the deck to fully dry.
Once your deck is clean, dry and free of raised fibers, you are ready to stain. Just as with deck cleansers, there are a myriad of deck staining products on the market to choose from.
There are three main categories of deck stain: Oil-based, water-based and acrylic-based.
Oil-based stains are the most popular among both homeowners and professionals, due to their ability to deeply penetrate the wood, which allows for better protection from moisture.
Water-based stains do not penetrate the wood deeply as oil-based stains do, but they do provide protection from the elements, and are very easy to apply and clean up. Also, water-based stains don’t release volatile organic compounds (VOCs), and are therefore considered a safer product to use.
Acrylic-based stains are a newer product on the market. They apply very quickly, and have a similar performance to water-based stains.
Once you’ve chosen a stain, thoroughly reading the instructions is essential. A paint brush will provide the deepest penetration, but sprayers and rollers are becoming more popular since they take less time. One of the keys to a good finish is to not over-apply the stain. When too much stain is applied, a film can form that may peel or crack over time. It is generally best to work from the top down, so all of the rails should be stained first. Then the stain should be applied beginning at the area adjacent to the house. Finally, be sure to allow at least 24 hours for the stain to dry before using the deck again.