3/4" 4x8 Fire Retardant Ply 70.4#/SHEET 2200#/MSF IMPORTANT NOTE: Lumber & plywood weights can vary widely depending on the time of year the material was produced and the location of the producing mill. Default is 50 psf which you can change. A standard 28 softwood lumber needs spacing at 16" o.c. The load capacity of a 3-foot #2 grade 44 is 17,426 pounds, and a similar 66 is 20,834 pounds or 16% better. If your 22 is 12 feet long, multiply 12 by 0.44 to get 5.28 pounds. You are using an out of date browser. Glued and screwed) That is stronger than a 4x4. Always use eye protection and gloves when operating power tools. 3000/1500 is 2. It does not have the strength of solid wood but it can sustain a small to medium load at a much cheaper cost. //-->,