When cleaning is the correct alternative:
The first procedure is to remove the dirt from the wood surface utilizing a cleaning agent, followed by a low-pressure rinse with water resulting in a clean surface. A wood brightener is applied to remove discoloration caused by tannin bleed, nail or screw rust stains, and a neutralizer to restore a rich new wood appearance.
When sanding is the correct alternative:
The first procedure is to check the countersinking of the deck screws. Deck screws have a coating to protect from rusting, if the protective coating is removed by sanding the screw will be susceptible to rust. The correct grit of sandpaper is the next decision. When a new deck is to be finished, the removal of a mill glaze is necessary before staining and a lighter grit sandpaper would be used. If the surface of your wood deck is older and is rough, uneven, splintered, or has raised grain a heavier grit would be used first followed by a lighter grit for a smooth surface.
Choosing the correct type of stain will depend on many factors. Stain must be water repellent, provide protection against UV ray deterioration, last against wear and tear, be flexible for expansion and contraction of the wood, are microporous to allow moisture in the wood to escape and contain a fungicide. Depending on moisture, sun exposure and foot traffic the type of stain you decide on will dictate the frequency of finish maintenance. Each of the below listed stain types will meet variables of your needs.
Level 2 Stain
Semi-transparent or semi-solid stains have a heavier pigmentation with selected colors resulting in a subdued look for the wood grain. It also offers protection from moisture and UV rays, as well as foot traffic. This stain will protect the horizontal surfaces for 2-3 years and the vertical surfaces for 3-4 years.