How to Remove Mildew Stains on a Deck
- 1). Mix vinegar and baking soda together in a large bucket. This will create a foaming mixture that will remove mildew and algae stains and kill mold, mildew and algae that may be living in the nooks and crannies of your deck. Whether you have a wood, composite or concrete decking, this mixture will remove mildew and many other stains.
- 2). Pour a small amount of the mixture on the deck and use a push broom to scrub it around. Treat and clean a 3-foot square area at a time until you get the whole deck treated.
- 3). Allow the mixture to sit on the deck for about 30 minutes before going over it again with the remaining mixture in the bucket and the push broom. This will help make sure that any mold and mildew spores are killed and that the entire surface of the deck is scrubbed clean.
- 4). Use a hose to rinse the deck with water to remove the whitish film that the baking soda may have left.
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