Are boat covers waterproof? How to make them waterproof?


Whenever boat maintenance is considered, boat covers are an absolute necessity. Since a boat cover is a crucial element to consider, Will the same boat cover protect the boat during rains by repelling water completely? Are boat covers waterproof?

All boat covers are not waterproof, but most of them are water-resistant, meaning they do not naturally repel water entirely but, instead, they don’t let the water soak through. However, by spraying waterproofing sprays on a “normal non-waterproof” boat cover, you can waterproof it fully.

The terms “waterproof” and “water-resistant” might seem like interchangeable terms, but they are not. Waterproof covers will repel water completely. On the other hand, water-resistant covers do not inherently repel water but, rather, are treated not to let the water soak through.

Boat cover fabrics specified as waterproof are usually vinyl, vinyl-coated or laminated, and the ones specified as water-resistant are usually acrylic or polyester or other materials other than vinyl. So, all boat covers are not waterproof, but most of them are water-resistant.

However, most of the boat covers can be waterproofed by using waterproofing sprays like 303 Fabric guard or Star Brite, or any other products. But once the waterproofing substance wears off, your cover (and the part of your boat is protected) is no longer kept dry.

Eventually, even the waterproof boat covers will lose the waterproof ability down the line. They need to be waterproofed periodically every two or three years based on the usage to keep them in a working condition. So, every boat covers need to be regularly re-waterproofed to repel water completely.

Should you cover your boat when it rains?

Well, boats are meant to be used in the waters (moist environments). Does it really hurt your boat when it is uncovered in the rain?

Boats should be covered during rain because it not only damages the boat’s interior but can also flood the boat with rainwater if the bilge pump is incapable of pumping out water or if the drains are plugged with trash or any. And boats without covers are vulnerable to insects, sun, rain, snow, etc.

So, it is essential to cover the boat with a “waterproof” cover when it rains. Even the water-resistant fabrics do not inherently repel water but, rather, are treated not to let the water soak through. If it is a normal boat cover (not water-resistant or waterproof), it’s better than no cover at all.

Waterproof boat covers will protect the boat during rains by repelling the water completely. Yet, the rainwater will not sink the boat, but in heavy rains, there is a possibility. Later it will be a mess if you didn’t cover the vessel or used a cover that isn’t waterproof.

However, occasionally leaving the boat uncovered in the rain for an hour or two is OK, but ensure the bilge pump is working well enough and the scuppers (drains) are clean without any debris or trash blocking them. But the cover is essential if the boat is kept in the waters.

And it is a good practice for every boater to remove the boat from the water when it rains and properly waterproof (cover) the boat, which will protect the boat from rains and other damages.

The advantages of using waterproof boat covers

Waterproof covers protect the boat from rains

Waterproof boat covers will protect the boat during rains by repelling the water completely. However, the rainwater will not sink the boat, but in heavy rains, there is a possibility. Later it will be a mess if you didn’t cover the vessel or used a cover that isn’t waterproof.

If the water gets collected inside the boat, it will spoil the interiors and seats if you leave it like that for extended periods. You can prevent all of this by covering the boat during rains, especially by waterproofing it or by using waterproof boat covers.

Waterproofed boat covers look good (won’t fade)

Waterproofing the boat covers will give the boat cover a fresh or new appearance. You can forget about the color fading issue because waterproofing the boat cover will prevent the boat cover from fading even if it is kept outside in the sun for a long period.

Even if the boat cover fades (for which the possibilities are low), you can waterproof it again by using waterproofing sprays like 303 Fabric guard or Star Brite, or any other products in less than an hour or two.

The disadvantages of using waterproof boat covers

Ventilation could be a problem if the boat is covered for long periods

These waterproof covers won’t allow any air or water to pass through them. Condensation inside the boat could be a problem, resulting in causing mold or mildew due to the trapped moisture under the boat cover.

To prevent mold and mildew inside the boat, you need to select a boat cover with vents capable of releasing any air that may build up inside the vessel over time. If vents are not an option, you need to look for other cover materials (breathable cover materials).

Keep everything dry before covering the boat for extended periods. If water is present in the hull, it will evaporate over time. If the cover has vents, it is OK because the water vapors will escape through the vents. Otherwise, it will cause mold and mildew.

After taking the boat out of the water, just leave it for some time and remove all the water inside the hull and the bilge area (if any). Then wait for an hour or two and then start covering the boat. Now mold and mildew occurrences are less even if you use waterproof boat covers.

How to waterproof a normal boat cover?

If you are using a normal boat cover, you can easily waterproof the boat cover by following these two steps.

First, clean the boat cover properly

Cleaning the boat cover thoroughly before applying anything is crucial. If the boat cover is cleaned well enough, it will remove all the dirt from that, and when the waterproofing spray is sprayed, the (boat cover) fabric absorbs the spray well.

Use 303 multi-surface cleaner (check in Amazon here) to remove any tough stains on your boat cover. Spray the cleaner and wash it properly (scrub the stains) for some time. Then pressure wash it and wait for some time, let it dry. Then start spraying the waterproofing spray on it.

Spray the waterproofing spray on the boat cover

Make sure to spray it OFF the boat. Take the cover out and then spray on it; otherwise, the waterproofing spray can damage the gel coat. Just spread it out on some chairs or ladders or tables or on the ground and start spraying on it.

You can use any bug sprayer or any for that. Just pour the liquid into the sprayer, spray it on the boat cover. After completing it, wait for some time and let dry the cover completely before using it.

Check this helpful video on quick and easy boat cover cleaning and waterproofing a boat cover to visualize the above procedure.

Recommended (best) waterproofing sprays for your boat cover

  • 303 fabric guard (linked to Amazon) is a waterproofing spray for any canvases (not only for boat covers). It increases water and oil-based stain resistance, keeping fabrics dry and maintaining colorfastness.
  • Star Brite waterproofing spray (linked to Amazon) is a waterproofing spray for any canvases (not only for boat covers). Both of them are good products and protect the boat from repelling water and the sun’s UV rays. Try both of them and decide which one is good for your boat cover.

Recommended (best) waterproof boat covers

  1. Check this Sunbrella stormproof boat cover (linked to Amazon), and if you buy one now (on sale), you will get a support pole for free.
  2. For an all-around universal boat cover, it is highly recommended to use MSC Heavy Duty Canvas Boat Cover (check price on Amazon here), which fits a variety of boats, including V-hulls, tri-hulls, and runabouts.
  3. A support system is also crucial if you are keeping it outdoors in the rain or snow. For full support, also take a look at the Taylor Boat Cover Support System (check price on Amazon).

Sunbrella fabrics (linked to Amazon) are made from 100% solution-dyed acrylic. Therefore, they share many core characteristics like being breathable and UV, water, mildew, and stain-resistant. All Sunbrella fabrics are dyed to the core of their fibers, meaning the color will never fade due to prolonged sun exposure.

The carver fabric covers (linked to Amazon) also share many core characteristics like being breathable and UV, water, mildew, and stain-resistant. Consider both of them while looking for a boat cover, and choose the one based on your needs.

The key takeaways from the post

All boat covers are not waterproof, but most of them are water-resistant. Usually, boat covers made out of vinyl, vinyl-coated or laminated are waterproof, and the ones made out of acrylic or polyester are water-resistant. However, you can waterproof the boat covers by using waterproofing sprays on them.

However, down the line, even the waterproof boat cover will lose its waterproofing ability and needs to be retreated by spraying the waterproofing sprays like 303 Fabric guard or Star Brite, or any other products. Your waterproof boat cover will lose its water-repelling ability every 2 or 3 or more years, depending on the usage.

Waterproof boat covers will protect the boat during rains by repelling the water completely. However, the rainwater will not sink the boat, but in heavy rains, there is a possibility. Later it will be a mess if you didn’t cover the vessel or used a cover that isn’t waterproof.

Mahidhar

My name is Mahidhar, and I am passionate about boating. Every day I learn some new things about boats and share them here on the site.

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