Think your deck is impervious to damage because it's new? Think again. Even pressure-treated wood begins to deteriorate in less than a week if left untreated. Pressure-treated wood is highly resilient to pests and rotting, but it's still vulnerable to the harsh extremes of weather. Decks need year-round protection from rain, ultraviolet rays, molds and mildew. To protect your deck, try these expert tips: Preparation: If your deck needs a makeover, it will have to be prepared and treated first. To decide where to begin, perform the water bead test. Splash a few drops of water on several areas of your deck. If the droplets are absorbed into the wood, it's ready for cleaning. If the water beads, you will have to remove the existing sealant. Apply a product such as Olympic Stain Stripper to remove previous layers of oil and latex finishes. After sealant is stripped, replace any damaged deck boards and reattach loose decking before cleaning. Cleaning: To make sure the stain or sealant you apply is most effective, you will need to remove any dirt, algae, mildew or other materials first. Staining or sealing a dirty wood surface can cause premature failure of the stain's protective quality, and the materials trapped under the stain or sealant may continue to damage the wood. A cleaner such as Olympic Deck Cleaner lets you rinse away dirt and mildew, leaving the wood ready for protection. If flowers surround your deck, consider using a gentler formula, like Olympic Oxy Deck. Sealing: To identify the right type of stain, consider how you want the finished product to appear and how often you want to maintain the deck. For example, if you prefer the natural beauty of wood, select a clear stain or a toner. These allow the natural wood grain and color to show through, while protecting the wood for three to five years. If you prefer a finish with deeper color, semitransparent stains add additional pigment to the wood and offer added UV ray protection. For rich, vibrant colors and even longer protection of the wood, consider a solid-color stain. Olympic offers a full line of stains and sealants, ranging from clear sealants to solid stains. Once you buy the stain or sealant, apply it according to manufacturer instructions. All the products mentioned above are available at local home improvement, paint and hardware stores, as well as Lowe's Home Improvement Warehouses. Your deck will look better and last longer if you protect it against the elements.