Lifespan of composite

Pondering what the material/chemical breakdown and resulting lifespan is of fiberglass and Kevlar boats with gelcoat, stored indoors out of the sun. I am not talking about wear and tear, use damage, hatches, hardware rusting, of course. Typically, for well- cared-for boats stored indoors and out of the sun, does the composite material itself deteriorate after 20, 25, 30 years on its own disregarding where and how used?

I’ve seen nearly 30 year old Nordkapps
which seem fine as far as the integrity of the hulls and decks.

There are a lot of fiberglas boats around of notable vintage.

Potentially unlimited
The things with the biggest potential to damage the resin are UV, heat and chemicals.

Glass is essentially immune to damage from those. Other fibers a bit less so.

Provided that things have been stored out of the sun, kept cool and away from chemicals the life of a composite is potentially unlimited.

For example, my dad has glass fly rods that are in excess of 40 years old.

Fiberglass sailboats began production in large quantities over 40 years ago, and those hulls are not at all degraded. Many have been retired due to other maintenance issues, but the resin and glass are not weakened over that time frame.

I think the reality is that a glass kayak will get worn out through use before the hull degrades. And a boat that is babied to avoid wear should last a century. The reality is that it’ll be discarded long before then for a modern model, but the material should still be sound.

Composite whitewater boats
sustain gradual weakening where they are pounded repeatedly, even if overt delamination does not occur. They can be sun-damaged.

Certain old composite boats made with polyester resin, including one I owned, can blister and have weakened laminate due to minute amounts of water interacting chemically with the polyester. Certain older sailboats and powerboats have done this also. The cure has been switching to vinylester or epoxy resin, which are much less susceptible to this “hydrolysis.”

Some have maintained that hydrophilic fabrics like Kevlar and Nylon can absorb water into their fibers, swell up, and disintegrate the resin. This, in my opinion, is a suburban myth. I have never seen this happen in a whitewater boat, even though they are often wet inside, and Kevlar is often exposed to water by damaging blows.

Epoxy / glass panels kept directly
in non-stop SoCal sun will begin to show fiber on the surface after about 3 years. These are skin coat panels ( no gelocat ) Various pigments are effected less in same scenario. Little stength loss 'till a couple years later depending on laminate thickness.

So, stay out of SoCal?
Thanks, fortunately I don’t expose any of my composite boats to the sun without some protection.

How about Rotomolded Polyethylene?

– Last Updated: Mar-27-09 12:33 AM EST –

Kept out of the sun in a garage?? Can it last as long? could a poly last 40 years??

Why would you keep poly that long?
best upgrade I ever made was ditching my poly Looksha and getting a glass boat

2 glass yaks
laid up in 86 another 25 yrs. old , my first poly yak I bought in 93 an that was rotomolded in 89 , HA–the dbl. that was built in 93 actually looks the worst , but I bought it used from an OB camp

All have spent summer’s in sun atop the van as well as winter’s in NY-NC-FL so all the extremes .

Check back with me in another 10 yrs. !


Other than Pammy
who wants to paddle the same boat for 30+ years? Like vehicles, there comes a point where I’d just soon they fall apart to have an excuse to upgrade. So far, I’ve been rough enough that I’m confident I can destroy a boat in less than 10 years. With a $1000 boat that comes out to what $8 and change a month. I spend more than that at the vending machine.


Because glass doesn’t really deteriorate, when you change boats after 10 years, a glass kayak is likely to have held a lot of value. If you bought it used for say $1800, it can probably be sold for just a couple hundred less a decade later.

A plastic boat that you bought used for $1000, and used for 10 years? You’d probably be lucky to sell it for $200, because the material’s remaining life is questionable at that point.

Even if you don’t consider the performance and convenience advantages of composite, the lifetime of the material means the resale advantage is huge.

7 years
Any composite boat, but especially canoes (more unsupported area) will begin to rapidly deteriorate after about 7 years, regardless of storage.

At this point, the value will drop to almost nothing, and the boat will be completely unsafe for you or your family. Me, I’m a risk taker. As such, e-mail me with what you have and I will be willing to take these death-traps off your hands. Also, they might spontaneously combust, so write soon. Plastic after a few years starts to give of deadly fumes. I will take your plastic canoes too (I have a fume hood - well, just a regular hood on a paddling jacket but it will do.)

Glad I could help.

Are you related to
Or did you just go to the same school of canoe swapping?

Not old enough
I am not old enough to see how long a well cared for fiberglass boat will last and I am 69. I have seen boats from the late 50’s still in good condition. I have seen wooden stringers and transoms destroyed and the glass still looking good. One of the guys we paddle with has the kayak he bought over 25 years ago and except for a couple of recent minor scratches it still looks like new. He was really ticked when he scratched it after paddling it for 25 years. One of the jet ski liveries left a concrete anchor in shallow water. Of course his boat was exceptionally well cared for. One of the paddlers here picked up a glass boat built in 1984 at a yard sale for $225 and it is in good shape despite being neglected. Gel coat is dull but the boat is sound. Might polish out. His other boat is an old Sea Lion he picked up cheap.

fiberglass boats
The first fiberglass boat was built either in 1937 or 1942 (sources say one or the other) but the first production boats were in the early 1950’s. Some of those early boats are still in use, nearly 60 years later. I’ve got an early one, runabout built of polyester and light cloth, about a zillion layers, must have taken forever to build, but it’s still structurally strong. The modern resins are nothing like those the industry started with, much better. A modern glass boat if properly cared for will certainly last long enough that your grandkids can give it to their kids.

20-year-old Kevlar Spirit II

– Last Updated: Mar-29-09 10:12 AM EST –

Other than the usual dings and scratches, it looks as good as the day my father bought it. Unless someone does something stupid, it will be around long after I'm gone.

I’m keeping composite boats ranging
in age from 10 to 36 years of age, rather than reselling them and endangering the public. And those aerospace fibers would be massively dangerous if put in a landfill. My wife doesn’t understand, but our house must continue to be the “Yucca Flats” of spent composite boats.

We all must do our part to save the