Your deck is in full exposure to the elements and needs to be protected against them. You should waterproof your deck to ensure a longer life for it.
What can damage the deck?
The UV radiation from the sun can cause water buildup in your deck to damage the finish and make it look dull. They can also harm the resins in the wood and any color you have used on the deck. Changes in weather can also cause your deck to look weathered and start to fall apart early.
How do you know if you need waterproofing?
There are some tests you can do to see if your deck needs to be waterproofed. Although it is recommended that all decks are waterproofed, these tests will show if your deck is more at risk to water damage. Drop a few drops of water onto your deck and see if it beads up. If is forms into beads, then your deck is waterproofed and you are fine. However, if it is absorbed into the deck you need waterproofing. You can also use a piece of tape to check if the surface needs waterproofing. Lay the tape on the wood and press down; if it comes off with stain or some loose wood fibers, you will need to waterproof the deck. Visually, a deck that looks weathered and faded could use a fresh coat of stain to restore its vibrancy.
How do I start?
While you can always hire a professional to take care of the project, you may also attempt this yourself with the right tools and knowledge. Use a wood stripper and sandpaper to remove all the loose fibers of wood that have eroded off the surface and to remove the old stain that is flaking off. You should also power wash the deck before proceeding. You need to make sure that you have at least two days of dry weather before starting to stain the deck to make sure that it dries properly.
How do I apply the sealant?
You should choose a sealant with UV protection and one that matches the tone of your wood. Use a stain brush to apply the sealant and make sure that it makes it to the corners and steps, board ends, cracks and railings. You should wear rubber gloves to prevent skin irritation. You should also make sure you are not in direct sunlight to make sure the sealant does not dry too quickly without being absorbed into the wood. Allow 48 hours for it to dry and make sure you do not use the deck until then. Cover the deck if possible.
Waterproofing will add years to your deck and make it look new again.