Fiberglass vs kevlar

Outside of weight, is there a difference in performace and durability between the two fabrics?

I am mainly concerned with abrasion and impact. Is fiberglass durable and have a long life span?

48 bezillion power craft made with FG
can’t be wrong. Unless you are stopping bullets, I don’t see much difference except weight.And you keep both UV protected.

I might paddle the Rio Grande sometime
I should buy a kevlar boat in case I get caught between a Minuteman and the illegal immigrant he is shooting at.

I have had both…
in canoes and I think the big difference is just weight.

You should be just as careful with either material.

Keep in mind you can get ultalight variations which require even more care.



Kevlar is a LOT tougher…
…than fiberglass. While this doesn’t amount to a significant performance difference on the water there is a considerable improvement in durability.

Referring to Strings comments: With all due respect, most motor boats have “chopper gun” fiberglass hulls (shredded glass and resin sprayed into a mold – very thick) rather than the relatively thin walls of a resin/matrix composite lay-up (used by virtually all quality canoe/kayak manufacturers). In other words – no reputable canoe/kayak manufacturers use chopper guns – so the reference to 48 bezillion FG power craft is mute. As I say… with all due respect.

Good & bad in both
The boat manufacturer can make a bigger difference than the material. There are very durable fiberglass boats and lots of brittle ones. There are tough and light kevlar boats, and some very fragile ones.

Some will say S-glass is better for abrasion than Kevlar, but the skid plates made for Royalex hulls are kevlar. So the arguments will go on and on.

Look at older examples of the hulls you are interested in and ask the owners where they have used their boats. That will give you an idea of how the boat has held up to the usage.

I have both glass and kevlar Wenonah’s. There have been no problems with either and all my hulls have serious end to end scratches from loaded encounters with rocks. The glass Wenonahs have kevlar strips along the keel line and up the stems as part of the factory layups. One is pushing 25 years and has thousands of miles of wilderness travel and thousands of miles of offspring paddling(3 sons,dozens of friends).

Pick your hull based on what you want to carry vs what you can pay. A couple trips to the Chiropractor covers the difference between glass and kevlar very quickly.


I have a solo expedition canoe that has 12 layers of kevlar in the hull this is 9-10 layers MORE kevlar than ALL canoe and kayaks manufactured in North America. So you can see that in short, my boat would be really tough. I have lost it off the roof of my truck at 50 mph and watch it bounce down the highway resulting in a few scratches. I have dropped it , smashed into logs, rock, barges and dragged it over trees and across rip rap without anything but scratches.

So to answer your question, it would depend on how well the kev or FG is made and how many layers etc. I know of no other boats as durable and probably the reason why i have a lifetime gurantee on it.


I was only
aware of one power boat mfg. using chopper guns. Cruisers, Inc. I am more familiar with the larger than trailerable boats, but I thought most were using hand lay up, with the high end manufacturers vacuum bagging for higher strength/weight ratio.

is easier to repair.

Wait…who made it?
I would just add that it makes a world of difference between manufacturers. Some glass lay-ups I’ve seen are very poor even in a good name brand boat and others are as strong if not stronger than top name brand kevlar boats so you need to look beyond just the two fabrics. even when and where a boat was made make a big difference. Some much older glass boats are damn near bomb proof compared to some of the paper thin new ones from the same company! Like so many other things going on today, as companies change hands cost cutting and speed of products going out the factory door comes into play. Look around at how different companies make their boats and ask questions. I don’t want to start naming names here but some canoe companies (and kayaks) are much more trusted by those who know.

Kev vs. Fiber
Kev generally has the advantage as far as tear resistance goes, a good example being the fact you need specialized scissors to cut it, glass you don’t. Kev being a tighter, thinner strand and weave also takes on less resin. the thicker the resin and cloth combo, the more brittle or prone to cracking. Add in the lighter weight, also an end product of less resin, and your portage weight drops by around 20%. As far as the comments on the light weight Kev needing to be babied, my Ultralite Kev Odyssey has taken more abuse and hits in Canadian waters with a full load than you usually like to see and only suffered peach fuzzing of the cloth on the bottom. the boat is over 13 years old and still showing plenty of life and integrity.