- 1). Brush any dirt and debris from the canvas with a broom. Mix 4 oz. chlorine bleach in a bucket with a gallon of water. Apply the solution to any stained areas with the broom.
- 2). Wash the canvas thoroughly with a natural, mild soap --- using harsh detergents will strip any waterproofing agents that have been applied to the fabric. Rinse the canvas thoroughly with a garden hose. Carefully examine the underside of the canvas for leaks or drips.
- 3). Allow the canvas to dry thoroughly. Apply a silicone based water-proofing treatment, approved for canvas products, with a large paint brush. Apply the treatment, according to the manufacturer's specifications, to the outside of the canvas over any areas where leaks were discovered.
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