UV degredation in poly kayak

I have a 10 year old, 13"10’ polyethylene kayak currently being stored at a relative’s house. It’s been in storage for the past several years: until last September inside a dark garage, hung on its side from the rafters by nylon webbing. Since September, it’s been haning on its side on nylon slings, but it has been hanging from the side of a shed, outside and exposed to the elements. Not the best, I know, but it was the best I could do under the circumstances.

I’m finally going to take a road trip to pick it up and bring it “back home” once and for all. How much UV degredation should I expect? I don’t know how much sunlight it gets per day (it was raining out the day we hung it up), but I know it’s not in full shade. I also didn’t get a chance to treat it with some 303 Protectant. I’m hoping that, since it didn’t spend the summer in the sunlight, it will be in good shape.

Anyone have an idea as to how quickly polyethylene degrades in Mid-Atlantic autumn/winter sunlight? I’m hoping to get another season or two out of it. Thanks.

I wouldn’t worry about that amount of UV
exposure, but a boat that old may be a little more likely to crack under heavy use. If you’re just paddling flat stuff and beaching it gently, you’ll get another season.

What brand is it? There are major differences depending on how much UV-stabilizers and anit-oxydants where added. I asked Prijon (a german brand) a while ago and the answer was:

  • UV stabilizers work for at least 15 years
  • color bleaching will start depending on UV exposure after 8 years
  • there are boats older than 20 years still in use
  • there are younger boats that already can’t be used no more, they break

    So enjoy another 5 to 10 years, but store it in the dark when not in use. UV is most important.

and they’re fine. And our year is worse than your. UV-wise, I would imagine.

If you’re REALLY worried about it, you can continue to store them as you have, but buy an opaque tarp to protect them against the sun.

And go over them a few times with 303, basically an ‘Armour-All’ for PE (do NOT use the real Armour-All, it actually DEGRADES poly…!) 303 is a good, but not inexpensive, protectant for plastic. I use it on our all our fleet -4 PE, 1 glass, and 1 Trylon -of boats.

Our boats are racked -a DIY affair I built that you can see below:

(New setup)



(Old setup)


As you can see, the rack is outdoors in our back yard, under the palms, and avoids most of our direct subtropical Miami sun. I no longer cover the boats, but wipe with 303 as noted.

Other US areas will generally be less exposed to UV than we, and since we’re doing fine, you will too. You should be able to outside store -and enjoy -your boat(s) with just a little care and maintenance for years to come as you


-Frank in Miami


– Last Updated: Apr-15-05 8:59 AM EST –

The amout of exterior color fading should give you an idea of how much UV damage has been done. Compare the color of exposed areas to non-exposed (like inside the coaming.)

I avoid Armorall too, but I don’t
believe that it can degrade polyethelene.