Read the beginning of the story How to buy Hardwood lumber and Save . Mill talk made easy (differences between big wood trading home centers and lumber sawmills) The contrast between the big-box home centers and a sawmill requires explaining. When you go to a big-box store, you'll likely find kiln -dried red oak lumber and poplar planed or surfaced on two sides in 3/4 -thickness(nominally referred to as 1'” thick) in standard widths that include l x2, lx3. lx4, lx6, 1x8, and lx12 . Lengths extend to 12', but you can have boards cut to shorter lengths upon request. All of it is edged to remove wane. At sawmills, rough stock comes in random lengths and widths and in several nominal thicknesses, such as 4/4 ("four/quarters" or 1~), 5/4 (1';.") , 6/4 (1'/")' 8/4 (2'), and so on. These thicknesses, though, 1 are designated and the board footage calculated before drying and surfacing. You pay retail for the original green thickness, ...