How to Waterproof Canvas Top

Applying waterproof spray to a canvas top will help it repell water and prevent the accumulation of mold.

If left untreated, outdoor fabrics -- like camping canvases -- can be rendered unusable due to the accumulation of molds and mildew that result from water damage. But preserving outdoor materials isn't too hard. After applying a couple of coats of waterproof spray to your canvas top, you can make the fabric water repellent to help ensure that people and equipment are kept dry in wet weather.

Things You'll Need

• Gloves
• Waterproof spray

Instructions

1. Spread out the canvas on a table or on the floor. For large canvases, you might have to go outside and spread it on your deck or lawn.

2. Coat the entire surface of the canvas with waterproof spray. Waterproof spray is a silicone or fluoropolymer product that can be applied to materials and fabrics to help them repel liquids. The spray is often used to treat camping gear and outdoor equipment. To apply, put on gloves and then spray the canvas in rows so you can easily see if any areas are missed.

3. Allow ample time for the waterproof spray to dry. Generally, it is recommended that you let the canvas dry for 72 hours after application to ensure that the spray has had time to completely set in.

4. Treat the canvas again with a second coat of waterproof spray for added protection against rain and moisture. You can also spray the edges on the underside of the canvas to help prevent unwanted leaks or dripping.

5. Allow another 72 hours for the spray to set in before using.

Tips & Warnings

• Waterproof spray can be purchased in many hardware stores and sells for about $5 to $10 a can.

• Check the label on the waterproof spray to make sure it safe for use with fire retardant fabrics.

• Always spray in a well-ventilated area.

• Avoid spraying in windy locations.

References

• Boatus; Waterproofing Canvas; Don Casey
• Waterproofing Spray: Home