How to increase water resistance of a tonneau cover?

You could increase the water resistance yourself by choosing a better type of tonneau cover. A painted one-piece tonneau cover is the best you could go with. This has a single piece of fiberglass or ABS plastic that goes all the way from front to back. Hard roll-up or hard-folding tonneau covers also provide pretty high water resistance.

Will a tonneau cover keep water from entering my truck bed?

The short answer to this question is, when properly installed, a tonneau cover will keep the vast majority of water from entering your truck’s bed. To describe a tonneau cover as 100% watertight or waterproof would be inaccurate, but the most you’ll usually get are a few drops intruding during a rainstorm.

Are tonneau covers waterproof?

Some hard folding designs like the Extang Xceed incorporate a vinyl lining across the top of the cover that further improves water resistance. This level of water resistance contains two tonneau cover categories: soft roll-up and soft folding.

What is the best roll-up tonneau cover?

The BAK Revolver MX4 is the clear choice if you want max security from a roll-up tonneau cover. Underneath the tasteful vinyl layering lies a sheet of aluminum panels. While aluminum isn’t the hardest metal, it’s certainly not something thieves can slash through with any old knife in seconds.