While it is important that a deck needs to be protected from the weather it can make things worse by applying stain on a surface that has not been cleaned. Prior to applying a deck stain the wood should be free of dirt, mold, mildew, graying and any old failing stains. A clean bare wood surface will absorb the new stain so it performs and protects as expected. Not only will a stain protect when applied to a clean surface it will help enhance the beauty of the wood creating a stunning finish.
Cleaning a deck can be done with a wood deck cleaner or a wood deck stain stripper. Both will clean the wood thoroughly prior to staining. When deciding, “do I strip or clean before applying a deck stain,” take into consideration the condition of your wood surface. If the wood is just aged, dirty and grayed then a quality wood cleaner can be used. While a wood cleaner may remove some transparent or semi transparent stains, a deck stain stripper is more effective.
When dealing with a deck or wood surface that has remnants of an old failing a stain stripper should be used instead of a wood cleaner. A stain stripper will soften and emulsify most semi transparent and semi solid deck stains so they can be washed or scrubbed away. A stripper will also clean dirt, mold and graying so there is no reason to use a wood cleaner following a wood stripper. Use one or the other. Clean to remove dirty grayed wood or strip to remove these pollutants in addition to an old failing stain.
Always after performing a strip or clean before applying a deck stain, you should neutralize the stripper or cleaner using a wood brightener. A brightener will lower the pH of the wood to brighten the grain and open the wood pores for accepting stain. If you are not sure if your deck has an old stain or sealer on it you can perform a water test. Sprinkle some water onto the surface. If it absorbs quickly it is likely that no stain is present. However, if it beads up and is repelled by the wood then a stain or sealer may be the culprit and a strip should be performed to remove it.