Fornesto, I'm thinking that the big difference would be the straight-ness of the material. Thicker ply will be flatter, and give you a straighter wall. I'm currently building with a built-up wall of 1/4 ply, framed out with 3/4 furring and insulated. The benefit I see to this method is, that you can build a flat wall that is lighter and insulated as well. The wall will be 1-1/4" thick. As for sheet sizes, if you are covering the Tear in aluminum, splice 1/4" sheets along a furring strip. If you want the wood look, I made 11-foot by 5-foot panels for the Lil'Diner by a little "creative" splicing. If included in some sort of built up arrangment, strength is no problem. Although, cutting can be a little nerve-racking! This is my twin of Mike's 'Diner. Birch/Scraps of Mike's Cherry ply/Birch.
