The Truth About Boat Covers: Are They Waterproof?

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Boat covers are a necessary purchase for boat owners. Not only do they protect the boat from the sun and weather, but they also keep it clean. However, one of the biggest questions boat owners have is whether or not boat covers are waterproof. In this blog post, we will answer that question and give you some tips on how to choose the best boat cover for your needs.

Most boat covers are surprisingly not waterproof! If you leave water pooled up on your boat cover, you will quickly find that it drips through the fabric and into your boat. This of course is not great for people hoping to keep the floors of their boats intact and mold out of the interior.

While boat covers are not inherently waterproof, we are going to talk about some ways to mitigate this issue, and help you keep your boat as moisture free as possible!

Always prop up your boat cover for drainage

One way to help boat covers dry out faster and prevent water from pooling is to prop up the cover. You can do this by using boat cover supports (like these) or even just some old boat cushions.

By propping up the cover, you allow water to drain off the sides of the boat, rather than pool, which will help keep your boat drier for longer.

Spray your boat cover with waterproofing spray

Another way to waterproof your boat cover, and one that we highly recommend, is to use a waterproofing spray. These sprays help repel water and make it bead up on the surface of the boat cover. This not only helps to keep your boat drier but also keeps mildew and mold at bay.

We recommend using a waterproofing spray like this one, which is specifically designed for boat covers.

You should keep in mind, that this should be used in tandem with the boat cover supports from the previous section. Even this spray will not help with pooled-up water on boat covers.

Use a second boat cover

Many boats have a custom boat cover that snaps over the open areas of the boat, however, it is also best practice (in wet weather), to fit a universal boat cover over the top of this! This will serve as an extra layer of protection against water and will help to keep your boat drier in storage.

What if I already have water in my boat?

If your boat is already wet, the best thing to do is to remove anything that is not waterproof from the boat. This includes items like electronics, clothing, and cushions. Once these have been removed, open up all compartments and hatches to allow for air circulation.

If possible, prop up your boat cover so water can drain out. Finally, use a shop vac to remove as much water as possible from the boat.

Now that you have air circulation, and have gotten most of the water removed from your boat, you should be keeping something like a DampRid (linked here), to continue to collect any extra water that is in the air, and the boat.

What happens if the interior of your boat is in the elements?

You likely have noticed your neighbor’s boat that has been left without a cover on it, slowly being destroyed by the elements! Not only does rain damage the flooring, by rotting it away, but the sun will bleach, crack and split the seats and all of the plastics in the interior of the boat.

Leaving the interior of your boat out in the elements is a surefire way to decrease its lifespan, and will leave you with an expensive repair bill down the road.

Is my boat OK in the rain?

Brief exposure to the rain will not damage your boat, but it is best practice to cover it up as soon as possible. Generally speaking, if a boat is out longer than a couple of days at a time, I try to make sure that it is completely covered to keep it from getting damaged over time.

If you leave your boat out in the rain for extended periods, you run the risk of damaging the boat’s flooring, seats, and other materials.

It is also important to note that if you have an open boat, you should avoid driving in the rain as this can cause water to enter the boat and damage the interior.


While boat covers are not waterproof, there are ways to help make them more water resistant and prevent water from damaging your boat.

I am really not quite sure why people like to leave their boats out in the rain and sun without covers, and allow the water to seep in through the boat cover over time.

Boats are by no means a cheap investment, and taking care of it is important.