Ultra Violet exposure damage question

I am aware that leaving your kayak out in the sun can damage both polyethylene and fiberglass kayaks; I have one of both. I store them for long durations in a garage that I rent. However, there are some days where I kayak almost every day for four or five days straight. Will leaving them locked and strapped to my car for that amount of exposure do serious harm? I thought about putting a tarp over them but that would be a huge pain in the ass. Do any of you think that it’s too much exposure for say week on top of the car in the sun? When I can, I try to park it under a tree in front of my place. Please let me know what you think; I would much appreciate it.

not a problem
I know more about plastic kayaks than composites, but I suspect this holds true for both. Manufacturers do put UV stabilizers into the plastics they use. This makes it so it would take a reasonable amount of time before damage. So only if it was out for many months, or even years, on end would I worry.

I would put 303 on any plastic kayaks as that is supposed to help for sunlight exposure. To keep gelcoat from fading put on Klasse its an acrylic sealer. It will last a whole summer long unlike wax which last 1 month if that long depending on surface temp. You can buy Klasse online at many stores. I learned about Klasse 12 years ago when I bought my first new car. I wanted the paint to last. Buffalo NY winter is tuff on car finish. There are a few other brands of acrylic sealer but Klasse has been around a long time. Your gelcoat wont fade if it has Klasse on it. Not for plastic, use 303 for that.

303 marine protectant is inexpensive and easy to apply… works like sunscreen for your boat. Reapply a few times per year…

We keep two composite kayaks
on the vehicle roof when they are not in the water for four months every winter in the bright Florida Keys sunshine

As the posts above say, just give them a coat of 303 every so often, and that would be more for keeping the color from fading

If they were poly, I would loosen the straps if they are sitting there for a while and not used.

UV rays will definitely hurt any ultralights with a clear coat. We keep our clear coat Kevlar Jensen covered

Jack L

Any exposure at all to sunlight will instantly destroy any kayak.

Kayaks are only usable at night, or on rainy days.

Don’t ever use a kayak of any type on a sunny day!

Sarcasm as syrup
Easy there with the sarcasm in MintJulep. No need to lay it on that thick.