How to Finish Cedar Decks
- 1). Scrub the deck if it is not newly laid. It is best to finish a deck right away to enhance its life. The cedar needs to be clean to finish it. Wet the deck and hose off any debris. Use the scrub brush to get mildew and grit out of the grain. If necessary, sprinkle on oxygenated bleach and mist with the water. Scrub with the bleach to lighten stains and remove grime. Rinse thoroughly and let the deck dry for several days.
- 2). Sand any areas of the deck that are not smooth. The cleaning will have softened the wood fibers and some may have pulled up. Corners and ends should be sanded to open up the grain. The goal is not to make the wood smooth as glass, but to remove imperfections and burrs that would be hard on bare feet and hands. If the entire deck needs to be sanded, use an orbital sander. Rinse the deck lightly or sweep off the sawdust.
- 3). Stir the water repellent to incorporate the oil and solids on the bottom. Pour some into the paint tray. Starting in the center of the deck, use a roller dipped into the repellent to apply the product. It will be thin and drippy, but will soak into the wood readily. Apply the product on a dry day when temperatures are at least 60 degrees Fahrenheit but do not exceed 80 degrees Fahrenheit.
- 4). Use the paintbrush on vertical surfaces and corners. Do not worry about overlapping lines or uneven color with the water repellent since it is clear. Allow the product to dry for 24 hours or until it is no longer tacky. Check to see if you need to reapply in any areas by looking at how dull the board looks. Fully cure the deck for two days before walking on it.
- 5). Treat the deck with water repellent annually. You will have to sand more as the deck gets older. You can always add a stain over the water repellent, but stains are harder to apply because you need to worry about overlapping. Roll the stain onto individual boards in their entirety to get even coverage. Then move to the next board and completely coat it. Stains will last about two years.
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