I have taken to varnishing the whole inside. I have found that one layer of cloth without a fill coat of epoxy can be somewhat porous. There will be small pinholes that will let a small amount of moisture into the wood. While I have not yet had any problems beyond small stains due to this moisture penetration, I don't like it.

You could solve this problem with a light fill coat of epoxy. I have been using a couple coats of waterbased varnish. The waterbased is low viscosity and should penetrate the pinholes. It also drys quickly, permitting several coat in rapid succession. The varnish is easy and has the added benefit of providing UV protection.

I have also started paying more attention to drying out the inside of the kayak between uses.

: Hi everyone,

: Is it necessary to varnish the inside? I saw it in Tom Moore's book, but I
: don't think that I've seen a reference in Nick's book or in Joe's
: instructions. I tend to use a cockpit cover when I don't use the kayak.

: I don't like the idea of sanding the inside since I would end up in the cloth
: which I think is worse.

: The commercial yaks don't have varnish either on the inside.

: Any advice is welcome.

: Andreas