- 1). Lay plastic dropcloths underneath the deck and around its perimeter to protect vegetation. Put on rubber gloves, long clothing and eye protection to prevent exposure to the oxalic acid solution.
- 2). Prepare an acid-based wood restoration solution to remove the gray discoloration caused by sun damage. In a plastic bucket, mix 4 oz. of oxalic acid crystals with 1 qt. of water. Follow the oxalic acid manufacturer's instructions.
- 3). Wipe the oxalic acid solution onto a wood plank. Concentrate on one deck board at once. Scrub the plank with a deck brush to brighten and restore the wood's hue.
- 4). Rinse the wood plank using a garden hose with a spray nozzle. Flush away the oxalic acid solution completely.
- 5). Wash each remaining wood plank, step and rail in the same manner as for the first plank. Focus on each deck component separately, and refill the bucket with fresh oxalic acid solution when necessary.
- 6). Wait three days for the deck to dry.
- 7). Fill a pump sprayer with clear deck sealer. Starting at the plank farthest from the deck's steps, spray the sealer over the wood. Hold the sprayer wand a foot from the deck surface, moving it back and forth to evenly distribute the sealer.
- 8). Continue applying the deck sealer as you work backward toward the deck's steps. Allow the entire deck to dry overnight before walking on it.
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