You may wish to consider lashings as used on traditionally constructed skin-on-frame kayaks. IMHO lashings will distribute stress and keep a joint intact long after screws have shaken loose. Some builders also use wood dowels for attaching the deck beams to the gunwales, but rarely is glue used. Traditional kayaks generally gain their strength from flexibility and resilience, rather than rigid stiffness. A potential problem with rigid construction is that once a little play develops, the damage can grow and feed on itself until the frame becomes very sloppy or fails. Of course the skin will help to keep the frame intact.

Also many builders of traditional frames simply use linseed oil to coat the frame. This approach has worked well, even here in hot, humid Florida.

Greg Stamer