Looking for experienced boat builders here. I am building an okume kit
kayak and am wondering if I can save weight by not placing a full glass
layer inside the hull.

My thinking is that I can get away with only glassing the butt joints
and edges on the inside along with a thin coat of resin for
waterproofing. Yes its going to be weaker (no fiberglass to take the
compressive forces) but has anyone done any tests to see how much
weaker?

If I have to I might just glass the cockpit area to help with required
durability (feet, stones and sand). Will this create any weird foces
beyond the bulkheads? (My boat will be 17 feet long).

Links to experiments on this would be great!

Thanks
Gary