My first kayak, a Chesapeake 17 was built with 1/8 inch luan. It cost $7.50 per sheet. I ran a sample through the dishwasher for a while and had no delamination. After I started building, I deceded to glass the inside as well using 6 oz cloth. The 1/8 inch material is difficult to scarf well so I used fiberglass butt joints. Overall the boat is very strong. It actually slid off my roof racks and hit the pavement. Only scratches to the hull. I have also used 1/8 inch luan for paddles and havent had any problems. I think that next time I build a stitch and glue kayak that I will cut out the panels and then glass the inside before I assemble it. Then after assembly, glass the outside. I also have a lot of cheap fiberglass, so that affects my material selection.