Pickup truck owners know the importance of keeping cargo protected from the elements. An open truck bed leaves your belongings vulnerable to damage from rain, snow, dirt, and more. A tonneau cover provides a practical solution by covering the bed, but how waterproof are tonneau covers really?
How Effective Are Tonneau Covers at Keeping Cargo Dry?
The main purpose of a tonneau cover is to protect the contents of your truck bed. Most covers will provide a decent barrier against water, but they vary in how watertight they actually are. Here are some key points on their water protection abilities:
Most Tonneau Covers Will Keep Cargo Dry in Light Rain
In light rain showers, most tonneau covers will prevent water from entering your truck bed. As long as the cover fits snugly over the bed rails and seals along the tailgate, it should deflect the majority of moisture. Even soft roll-up covers offer reasonable water resistance when properly installed.
Are Tonneau Covers Completely Waterproof?
While tonneau covers are designed to repel water, most are not 100% waterproof. Hard covers made from aluminum and fiberglass provide the most watertight protection. But even these may allow some water ingress during heavy rain or pressure washing. Complete waterproofing is difficult to achieve with folding and roll-up covers.
Proper Installation is Key for Maximum Water Protection
To get the most water protection from a tonneau cover, correct installation is essential. The cover must fit tightly over the bed, with minimal gaps along the sides or rear tailgate. Clamps, snaps and sealing strips should be used to create a continuous seal around the perimeter. A cover that is loose or poorly sealed will allow substantially more water to enter the truck bed.
Hard Covers Offer the Most Water Protection
Hard tonneau covers made of solid materials generally provide the highest degree of water resistance. The rigid aluminum or fiberglass construction allows for tighter sealing compared to soft vinyl covers. Retractable and hinged hard covers seal firmly when closed, offering close to watertight protection.
Soft Covers Can Repel Water if Properly Installed
While soft covers may not seem completely waterproof, most will effectively repel water when correctly installed and maintained. The key is ensuring complete side-to-side sealing and using fasteners designed to create a tight fit. Maintaining the vinyl cover and proper drainage are also important for water resistance.
How Much Water Will Get In Your Truck Bed?
The amount of water that enters your truck with a tonneau cover depends on the cover type and weather conditions. Here is an estimate of how much protection different covers provide:
Hard Covers Keep Truck Bed Essentially Dry
With hard covers like aluminum, fiberglass or vinyl-over-aluminum, very little water will permeate into the truck bed. Heavy rain or pressure washing may allow minimal seepage, but the bed will remain largely dry. These covers keep out over 95% of moisture in most wet conditions.
Soft Covers Allow Some Water Ingress
In heavy rain, soft covers will permit more water into the truck bed compared to hard covers. The flexible vinyl material and snap-on design mean they cannot seal 100% watertight. Some leakage can occur, especially in the cover seams, though the bed will be considerably drier than with no cover.
Storms Can Overwhelm Any Cover
In extreme weather like torrential rain storms or thunderstorms with high winds, most tonneau covers will allow substantial water ingress. The intense quantity and force of rain can inundate even heavy-duty covers. But your cargo will still fare better than being fully exposed.
Bed Preparation Also Plays a Role
How you prepare the truck bed also impacts moisture protection. Lining the bed with a water-resistant truck bed liner provides additional protection. Properly sealing the tailgate and managing drainage are also key for keeping your cargo as dry as possible.
Tonneau Cover Products to Keep Cargo Dry
If keeping your cargo dry is a priority, look for tonneau covers designed with maximum water resistance in mind. Here are some popular options:
Aluminum Hard Covers
Hard aluminum covers are securely installed using side rail clamps to create a firm seal along the bed sides. Models like the BakFlip G2 provide durable aluminum panel construction that is rain-tight when closed.
Retractable Hard Covers
Roll-up retractable hard covers, such as the GatorTrax, use vinyl-coated aluminum slats that provide exceptional water resistance. The low-profile design seals firmly over the bed for uncompromising protection.
Vinyl Over Aluminum Covers
Combining hard and soft materials, vinyl over aluminum covers offer rugged water protection. The UnderCover Flex has a solid aluminum base covered by weather-resistant vinyl. The smooth underside improves aerodynamics and fuel economy.
Fiberglass Reinforced Covers
Tonneaus like the Extang Solid Fold feature dual-coated fiberglass panels with an outer layer of vinyl. They fold for versatile access, while the fiberglass offers structural strength and water protection.
Soft Covers with Snug Fit Rails
For a soft cover, look for models like the Access Roll-Up that utilize thick vinyl and special side rails to improve the water-tight seal. While not impenetrable, they hold up very well against rain with proper installation.
Caring for Your Tonneau Cover
To maintain the water protection of any tonneau cover:
- Inspect seals and fasteners regularly for damage or gaps
- Clean vinyl covers occasionally with soap and water
- Ensure proper cover drainage to avoid standing water
- Follow the manufacturer’s care instructions
- Repair any holes or leaks immediately
Proper use and maintenance will optimize the cover’s ability to keep your cargo dry for years.
Is a Tonneau Cover Essential for Keeping My Cargo Dry?
While no truck bed cover is 100% watertight in every scenario, a tonneau cover will provide substantial protection from rain, snow, and other wet conditions. Hard covers offer the most water resistance, but even soft covers significantly limit water intrusion with correct installation. For pickup owners who need to keep cargo dry, a tonneau is an excellent investment.
Final Thoughts
- A tonneau cover can greatly minimize – but not fully prevent – water from entering your truck bed. The amount of protection depends on the cover type and weather severity.
- Hard aluminum or fiberglass covers provide the most watertight seal, though soft covers also significantly limit water ingress when properly installed.
- Ensure complete side-to-side sealing and use bed rail clamps for maximum water protection from any tonneau cover.
- Proper cover maintenance and drainage preparation are also key to keeping cargo as dry as possible.
While no tonneau can guarantee 100% waterproofing, installing a high-quality cover is an excellent way to protect your truck bed contents from rain and other wet conditions. With reasonable precautions, you can feel confident hauling cargo that needs to stay dry.