The conceptual design of wood members was presented in Chapter 6. The underlying assumption of design in that chapter was that an axial member was subjected to axial tensile stress or axial compression stress only and a flexure member to normal bending stress only. However, the compression force acting on a member tends to buckle a member out of the plane of loading, as shown in Figure 7.1. This buckling occurs in the columns and in the compression flange of the beams unless the compression flange is adequately braced. The beam and column stability factors CL and CP , respectively, mentioned in the “Reference Design Values for Sawn Lumber” section of Chapter 6, are applied to account for the effect of this lateral buckling.