A lot will depend on what type of rooftop tent you end up getting, what material its top is made of, and what strength it has. If you want to add a rack to the top of the tent, the tent will have to be a hardshell tent, of course.
I wouldn't hesitate to put a set of racks on mine, if I needed to, like a two-bar
Thule rack or similar, one with mounts you can bolt through the top of your hardshell tent. I would reinforce all mounting points on the inside with a backing plate, and use a
butyl tape under the rack mounts is to prevent leaks into the tent. A good RV roof type lap sealant like
Dicor is wise, too, to seal all entry points and bolt heads. I've used both of these products over the years, once to
install a roof vent in my van six and a half years ago. It's still doing great with no leaks, no problems.
How heavy is your kayak? Most canoes and kayaks are too heavy to leave on most rooftop tents when they're up, depending on the strut system used, but it might work. Worth considering too, is how much wind surface area will the kayak create up there, both for transport and if left on when the tent is up. It could contribute a lot to your tent getting shook around pretty hard in a wind. When you're sleeping up there, even the slightest movement feels magnified.
I thought about keeping my 14' canoe (only 28lbs) on top of my RTT on my trailer, but so far have opted to keep it between trailer and rack, as shown below. Keeps it below the van's roofline and out of the windstream going down the highway.
Good luck, hope you find a suitable solution.
~ Road
Roaddude - Traveling Photographer/Writer/Artist On the Road In North America. Gear, reviews, people, places, and culture.
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