There are several issues to consider. Sealing plywood is critical. My yak has several spots where water’s darkened the wood. Epoxy is a good sealer. Where epoxy is not stressed, a complete coat may be all that’s needed.

Strengthen wood with glass & epoxy. For puncture protection, glass goes inside. It’s insurance. Buy the insurance if you need the peace of mind! Otherwise no.

My S&G has some marks from rocks and the like. I used one 6 oz glass layer. There have been posts indicating better abrasion resistant coatings – graphite/epoxy. Maybe less glass and more ‘slip’ would work. Would I consider no glass? Not unless I was sure that an underwater contact neither let water reach plywood, nor left hard to repair damage. Maybe someone has done this already.

My $ .014 (2 cents Cdn.) Rick………

: Thanks. So it sounds like it is an issue of durability rather than strength.