Cotton canvas has a million uses in the yard and garden, but it can take a real beating from the weather. Mark Jansen explains how to waterproof your canvas awnings, tents, sunshades, and other canvas products to keep them looking good and serving you well for many summers to come!

How To Waterproof A Canvas

by Mark Jansen

There are times that we can never curb the forces of nature. This just goes to show that nature is, indeed, powerful and can destroy anything and everything. So, the only way we can do is to provide protection from the raging effects of nature.

One way to do this is through waterproofing. Waterproofing has been a great technique in preventing the penetration of water to any material.

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Whenever you waterproof a material, you apply a certain waterproof matter that is designed to provide utmost protection against the imminent effect of water. This, in turn, serves as a wall between the material and water.

There are many types of waterproofing. One of them is canvas waterproofing. This method is used particularly on materials made of canvas.

In most instances, the typical type of cotton canvas is already a waterproof material. Therefore, it does not need any waterproofing. Its fibers puff up whenever they are exposed to water, thus, it closes the knits of the canvas.

However, because of the canvas’ vulnerability to mildew and “bird droppings,” it is still subjected to canvas waterproofing. This is because canvas waterproofing does not only protect the canvas from water alone but also from other substances that can cause damage on the item.

So, for those who want to know about canvas waterproofing, here are some pointers you need to know:

1. Do not use silicone-based canvas waterproofing.

Never attempt to use silicone-based canvas waterproofing on acrylic canvas. Silicone clashes with the original application.

Normally, acrylic canvas primarily contains a canvas waterproofing chemical known as fluorocarbon, which in turn, repels the silicone material when applied. If this happens, it will result into an erratic treatment. Silicon can also eliminate the “stain-resistance” substance in the acrylic canvas.

2. Use a product with fluoropolymer.

When doing canvas waterproofing, it is best that you use a fluoropolymer-based substance. This type of canvas waterproofing is compatible with the acrylic canvas. Hence, it will result into a more durable and sturdy acrylic canvas.

3. Use a waterproof material that contains petroleum.

Petroleum-based materials have long been proven to be effective when doing a canvas waterproofing. They are very compatible with acrylic canvas. Petroleum-based substances work best in canvas waterproofing than those substances that are water-based.

The best way to identify a petroleum-based substances to be used in canvas waterproofing is to through its pungent smell.

4. When performing canvas waterproofing, do it outdoors.

It is best that you do canvas waterproofing outside the house because of the substance’s very strong odor. You might get suffocated once you do it inside the house. Therefore, it is best that you do canvas waterproofing where there is proper ventilation.

Besides, these strong substances used in canvas waterproofing can also damage your furniture made of plastics. So, it is a must that you take extra care when doing canvas waterproofing.

5. Use protective covers for sensitive furniture.

If you will do a canvas waterproofing on a canvas dodger, it is best that you protect your plastic furniture first before you start with the process. You can do this by placing foil over the plastic materials.

6. Do a spot test first.

It is best that before you start the process, do a spot test first. This is to know whether the substance used in canvas waterproofing will not discolour your canvas or cause further damage.

7. Remove the canvas from the boat.

It is best that before you start waterproofing, you should first remove the canvas from the boat. This is to ensure that the hard surfaces will not slick. Also, there are waterproofing substances that can cause a damaging reaction against gelcoat.

However, if you find this tedious and very unworkable, try to protect all areas vulnerable to “overspray” instead.

8. Let it dry first.

After waterproofing, let the canvas dry first before reinstalling it. In this manner, the pungent smell will soon be eliminated.

However, experts strongly suggest that after the canvas has been dried, it would be better to apply a second dose of waterproofing. This is to ensure durability of the material. It is still safe to do this and will not affect the fabric’s overall condition.

9. Reapply when necessary.

Repeat the process whenever the canvas is exposed in callous conditions. Though, experts say that after doing a waterproofing, the protection is guaranteed for one year at the least.

So, now that you know how to do canvas waterproofing, you can be assured that your canvas will always stay in top condition. As they say, it is better to prevent damage than to cure it.

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This Post Has 4 Comments

  1. Betty Rubble

    Hi, if I have already made the mistake of putting silicone-based waterproofing on acrylic canvas, can I cover it with a petroleum or flourochemical product?

    For other readers: Right next to two different silicone shoe & boot sprays, I found this at my local Ace Hardware:
    Scotchguard Rug & Carpet Protector
    “Repels Liquids – Blocks Stains”
    “Contains: isobutate; flourochemical urethane and ethyl alcohol.”
    I figure this is probably going to do the trick.

  2. Lee

    Hi – Can anybody recommend a petroleum based waterproof sealent ? the onlt product that I can find is Canvak and that is based in the US?



  3. Mandisa

    Hi Richard
    Do Fabric shops sell canvas that already has waterproof,which is usually used for making handbags?
    thank you

  4. Richard Brent

    I need waterproofing for a R V awning. This is an woven Acrylic fabric and is 18ft long by 8 wide. what would you recomend. Thank You.

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