UV degradation on an ultra light hull

I’m helping a friend purchase a used Wenonah Vagabond in an ultralight layup. We haven’t seen the canoe yet - just photo images. However, it appears the deck plates have faded from black to a grey color, unless Wenonah made grey deck plates at some time.

If in fact the deck plates were black and now faded to grey from sun exposure, should one be concerned about the hull? In this case it would be the interior hull that is of concern, since the faded deck plates suggest the canoe has seen a lot a time exposed to the sun with hull in the upright position.

If on personal inspection the hull interior looks fine, should one still be concerned?

Appreciate any insights. Thanks.

The inside of such canoes is made of
Kevlar cloth and vinylester resin. Contrary to past rumors, Kevlar does not deteriorate rapidly from UV exposure. It will darken, but that does not indicate a loss of strength.

So if you inspect the boat, the extent of darkening of the Kevlar could indicate the amount of UV exposure, but not necessarily the degree of weakening of the laminate.

What about the resin? Epoxy resin is more susceptible to UV degradation, but I recently saw a 20 year old epoxy canoe where the interior was still in good condition, just scuffed. My opinion about vinylester resin is that it is reasonably resistant to UV, more so than epoxy.

If the interior is scuffed and fuzzy in places, then that indicates a certain degree of wear. If the boat is otherwise sound, then a coat of UV resistant spar varnish might subdue the fuzzies and add some protection to the interior.

As you can infer, I don’t put much weight on the degree of greying of the endplates. It is the actual condition of the hull, inside and out, that counts. But the boat will be used only on lakes and calm rivers, not rapids, so some surface wear may be irrelevant, if the price is good.

Your thoughts suggest to me as though anything we should worry about will be visible.

Not all discolorization
is due to UV exposure.

I got a canoe from the Adirondacks which at a northern latitude and heavily forested.

The deck plates were gray from oxidation. Applied rubbing compound and it was fine.

And pictures often look different from the actual thing.

What are your observations and
experience with UV and wear on the inside of Kevlar boats, both ultralight and flexy core? Do canoes with Kevlar insides show much inside deterioration from long use?

I have a Jensen that is 17 years old and
Comp cruiser that is 20 years old. both are ultralight Kevlar.

I have re- epoxied the outside of the hull on the Jensen due to many bad scrapes and scratches, but on both of them the inside has never been re-coated.

The only thing that happens is the gloss gets worn off.

I am guessing that the Jensen has more mileage on it then any other Jensen of the same age.

On both my wifes kayak and my kayak which are carbon/Kevlar, (carbon on the inside), the carbon has worn off where our feet go on the foot pedals, and I had to re-epoxy that area

Jack L

Are they QCC kayaks? They’re the only
ones I know of that use carbon inside and Kevlar outside.

I have a slalom c-1 that is carbon inside and S-glass outside, with a Kevlar foam sandwich deck, but it is a one-off prototype.