“Are tonneau covers waterproof?” is a very common question among truck owners.
The short answer is: they are water-resistant, but not waterproof.
Most weather-resistant tonneau covers, in order:
- Hinged Tonneau Covers
- Retractable Tonneau Covers
- Hard-Folding Tonneau Covers
- Hard Roll-Up Tonneau Covers
- Soft-Fold Tonneau Covers
- Soft Roll-Up Tonneau Covers
- Snap-On Tonneau Covers
Water-Resistant vs Water-Proof
The hard truth is that no tonneau cover can keep your truck bed 100% dry in rainfall. For that reason they cannot be considered waterproof.
However, they are water-resistant and during rainstorms, they will protect your cargo from most of the water.
But your truck bed may not be completely dry. You may still find some small amount has leaked in, depending on how heavy the rain is and if your tonneau cover has weather gaskets.
This amount is not worth worrying about since it is usually very little and can hardly cause any damage to your cargo.
And if your tonneau has weather gaskets, risk to your cargo is very low.
The level of water resistance is not the same for all tonneau covers. It varies significantly among the various categories of truck bed covers.
Let’s look at each and the level of water resistance.
1. Hinged Tonneau Covers
Hinged truck bed covers are some of the most water-resistant. They are usually constructed with one-piece fiberglass, ABS plastic, or ABS composite.
A hinged tonneau cover is not divided into panels then attached together like most. This is one of the reasons why it is very water-resistant.
In most cases, other truck bed covers are usually made of panels that are joined together.
When being attached, the gaps may close off completely.
It is through the space left that some water may manage to pass through into the truck bed.
Another reason is that, when installed, a hinged truck bed cover will overlap the tailgate and bed rails.
They practically cover the whole truck bed, including the sides, leaving only the rear hinges slightly exposed.
This makes it difficult for water to flow back into the pickup truck bed through the rails. Other elements like dust and debris will also not get in.
2. Retractable Tonneau Covers
Another tonneau cover type with a high water resistance is the retractable tonneau cover.
Retractable tonneau covers are popular for their convenience, low profile, toughness, and functionality.
They are designed with a canister, mounted at the truck’s bulkhead. When opened, the cover will retract into the canister, getting completely out of your way with full access to the truck bed.
The most common ones are aluminum, padded polymers, and polypropylene. Usually, the materials come in the design of slats.
Since they are not one piece, one would expect that they let in water through the joints. But that is not the case.
The slats are combined together with absolutely no space in between them. This ensures that no water creeps in through the joints.
To make retractable bed covers even more water-tight, they are fitted with compression seals at the tailgate.
Usually, the tailgate, and rails are the most vulnerable points.
So, the compression seal is always included at the tailgate, to minimize the amount of water that may get in.
As for the rails, they are designed in such a way that they channel water into the gutter system. The water is then directed into the drainage system and poured out of the vehicle.
The most reputable manufacturer of the retractables is Retrax. They manufacture both manual and electric.
3. Hard-Folding Tonneau Covers
Hard fold tonneaus are the security jargons and they come in either tri or quad fold.
While they do not match the hinged tonneau cover’s water resistance, they also resist water pretty well.
For practical purposes, a well built hard-folding tonneau will still be resistant to most water leakage.
A hard truck bed cover is usually constructed from aluminum panels. Some are also constructed from fiberglass and hardened plastic.
This makes it very difficult for a thief to cut through them.
In the same way, water cannot pass through them into the truck bed, except for vulnerable places. These are the rails, the tailgate, and the joining points.
To counter this, manufacturers usually include watertight seals along the rails.
Most of these hard folding covers also come with drainage tubes to channel water out of the vehicle.
Additionally, some manufacturers include vinyl lining on the tonneaus across the top. This makes them even more resistant.
4. Hard Roll-Up Tonneau Covers
Most truck owners prefer this type of rolling truck bed covers because they offer the best of both worlds.
A hard roll-up truck bed cover has the easy operation and sleekness of a soft rolling tonneau cover.
It is also tough and offers almost as good protection and security as the hard covers.
Similarly, the tonneau cover has great water resistance.
It is constructed using a series of interlocking aluminum panels. On top of the panels is usually a canvas or vinyl lining.
The lining covers any gaps between the interlocking panels.
This, together with the weather seals along the rails ensures perfect water resistance.
Only a small amount of water will manage to get into the truck bed.
Again, BAK Industries manufactures the best hard rolling truck bed covers
5. Soft-Fold Tonneau Covers
Soft fold bed covers come in the same design as the hard folds. The only difference is that they are made with an aluminum frame and a canvas or vinyl tarp. This makes them less strong than the hard folds.
But they are one of the most lightweight and affordable truck bed covers. They are also super easy to install and remove.
Unfortunately, the tonneau cover’s water resistance is not as high as the others already mentioned.
But this could depend on the manufacturer too. Some manufacturers include advanced watertight seals while some don’t, hence the difference.
This is not to say a soft-folding tonneau cover is completely not water-resistant.
A soft-folding tonneau cover always installs on top of the truck bed.
Because of this water usually flows down the sides, with just a little sliding into the truck bed through the hinges.
For these, TonnoPro is the best manufacturer.
6. Soft Roll-Up Tonneau Covers
Soft roll-up truck bed tonneaus are very common.
This is because they are affordable, lightweight, easy to install with no tools, and very sleek.
They also offer full access to the truck bed.
A soft roll-up tonneau cover has two parts; a frame consisting of support bows and rails, and a tarp.
The tarp is usually made of vinyl or in a few cases, woven fabric.
A roll-up tonneau cover is fairly water-resistant, though not as good as the hard rolling.
Soft roll-ups have weathertight seals. However, their construction is not very solid and might have some openings.
This type of tonneau cover will perform properly in places with less rain or snow.
7. Snap-On Tonneau Covers
Snap tonneau covers are not very common and they are among the oldest in the market.
They have the design of a soft rolling cover, except, instead of velcro, they have snaps as the sealants.
A snapping truck bed cover is made of a vinyl tarp and a frame of hardened plastic bows and rails.
Being a pioneer of the industry, the cover is not very advanced. Its water resistance is lower, making it not the best choice for areas frequented by rain and snow.
The key focus of the snap bed cover is affordability and it is also very lightweight and easy to store.
Extang manufactures the best of these.
Improving the water-resistance of your tonneau cover
You cannot make tonneau covers waterproof, but you can boost their ability to resist water.
This depends on which make and model your vehicle is. Most manufacturers provide these materials — if it’s included with your chosen tonneau, be sure to use them.
If they are not provided, yet your truck can allow, then you can buy and install them. Here’s what you need:
a. Add water-resistant seals
While some truck bed covers come with the watertight seals already installed, some don’t.
These are essential as they cover the gaps left between the tonneau cover and the truck’s edges.
Besides rain they also help seal out other weather elements like dust and debris
b. Install drain tubes
In most cases, you will need drilling for the installation process of the tubes. But that’s a small price to pay in order to make your tonneau cover more waterproof.
Generally, tonneau covers are constructed to protect your cargo and keep it safe from external elements: road, weather, or human.
But each cover usually has an edge at one point or another. While some of these are far from being waterproof, they are great in either looks, protection, operation, durability, access, and so on.
It is upon you to decide on your priorities and search for the cover that meets them.
As for water resistance, the hinged tonneaus are your number one choice.