As of 2015, two common types of canvas waterproofing products are Nikwax wash-in waterproofing and Star brite products. Canvas waterproofing products can be water-based, petroleum-based or solvent-based.
Star brite waterproofing products are popular with boaters, who use it to protect canvas covers and other products, although it can be used safely on most canvas products. Nikwax is popular for waterproofing canvas or cotton clothing, footwear and tents. It also makes products that gently but thoroughly clean the canvas surface before the waterproofing agent is applied, which can help protect any existing waterproofing capacity. Most commercial products use fluoropolymers to create a waterproofed surface.
Some people choose to use natural waterproofing agents rather than a commercial formula, such as simply adding a coat of wax. A blend of soybean oil and turpentine is also commonly recommended. There is more room for error with natural products, so people who use them should test them in a safe situation before the waterproofing is needed.
Acrylic canvas has some special considerations as well. Many waterproofing products use silicone, which can react with the acrylic fibers and degrade them over time, creating a flimsy fabric that provides little protection against the elements. Some canvas products are a blend of natural and acrylic fibers, so consult the manufacturer's recommendations before applying a waterproofing product.