The most troublesome of the warps is “twist”, for example, if a board has, let’s say, 1/16″ of twist that board will have to be face jointed and then planed to remove the twist, you will lose a minimum of 1/16 inch on each face leaving a board thickness of about 11/16″. A larger defect results in an even thinner board. If the board starts out in the rough, then losing 1-inch results in a board about 7/8″ thick. This points out the value of being able to mill your own lumber. Almost always a rough board can be milled to the desired dimension