I used Tom Yost's kayak design.
I have now built the 11' Sea Flea, the 14' Sea Pup and finally the 13' Sea Bee.
All were skinned with the cotton canvas you can purchase from your local fabric stores. Obviously you CAN go with a much stronger canvas if you feel you need to... but its been my experience that what I am using is sufficient for our typical use and abuse. The abuse and forgiveness it can take is why I chose it... along with the price. However... I also admit that I have never used nylon or other alternatives either. But if you want to know if you can get away with using a cheaper lighter weight canvas... yes, I have three kayaks built with it... Sealed with latex exterior paint and they are tough and durable.

Smiles,
~Heatherjen

: Ive been hearing talk about making a Kayak out of canvas, and was
: wondering what kind of canvas would i be using, and if there was
: anyone out there that might have some plan's that they could
: either share or direct me to a place or site where i could
: inquire about this.. Im looking to save money, but not degrade
: the structure of the kayak