Even though decks are mainly constructed with pressure - treated wood, the elements - sun, rain, and snow - and pollutants - such as dirt, tree sap, and bird soiling - still can weather and discolor them. A good application of a quality wood sealer and protectant can help to make your deck more weather resistant, but nothing can protect it permanently.
Besides the normal accumulation of dirt, if your pressure - treated wood deck has gray - black discolorations over it, these are probably mold growths. Algae and moss usually cause dark green blotches, and the sun, rain, and snow can weather the wood until it has a silver - gray cast across it. If your wood deck has any of these traits, then it's past time to refinish and care for it.
To start this project, you will need to clean the wood thoroughly. Sweep the entire structure off with a broom or with a leaf blower. Be sure that you clean out the cracks between the floor planks too. Then, you'll need to wash your deck with a good - quality cleaner and water. You can sometimes use a low - pressure washer to make this job quicker and easier. To actually clean your deck, some products require the use of brush or a mop. Read and follow the manufacturer's directions on the cleaner container in order to achieve the best results. You might need to pretreat any resistant stains before you clean the entire deck.
Note: Chlorine bleach is sometimes recommended for use in removing and killing stubborn mold, algae, moss, et cetera. Don't use this product on a pressure - treated deck, though, as the bleach can actually harm the wood. A good - quality cleaner that is specially designed for use on pressure - treated wood will work better and more safely. Chlorine bleach will also kill shrubs, grass, and other plants that it gets splashed on.
Next, rinse the cleaner off of your deck thoroughly with either the water from a garden hose, or by using a low - pressure washer. If there are still signs of dirt, algae, mold, et cetera, you might need to repeat the application of a good - quality cleaner.
Before you can re-treat the wood on your deck, you will first need to allow it to thoroughly dry. How long it takes to dry will depend on the weather. Refer to the manufacturer's directions on the container for a recommended time.
The next step is to apply the new stain or sealing product you have chosen. Again, it's important that you read and follow the manufacturer's directions on the container in order to achieve the best results. You should start staining or sealing your wood deck at the top. That is, apply the product to the railings, et cetera, first. You can apply the stain or sealing product with a brush, roller, or a spray gun. For railings and other smaller areas, a brush will work the best, though. The flooring should be done last, and can be successfully finished with a spray gun.
Finally, allow the wood on your deck to dry undisturbed according to the manufacturer's directions on the product container before you use it again.
Then, to keep your pressure - treated wood deck looking new and beautiful, you should establish and follow a regular maintenance schedule. This schedule should include renewing the stain or sealing product approximately every two years. In the mean time, you should care for your deck by sweeping or blowing it off on a regular basis. And, every month or so, you should spray it off by using a garden hose or a low - pressure power washer.
