What do you call the wood member that is at least 4 inches thick and 2 inches wider than its thickness, graded by bending strength?

The term for a wood member that is at least 4 inches thick and 2 inches wider than its thickness, graded by bending strength, is "Beams and stringers." This classification is particularly important in construction, as beams are primarily used to support loads and transfer weight to columns or walls.

In the context of structural engineering and construction, beams must possess specific characteristics to perform effectively under various loads. Grading by bending strength ensures that the beams can withstand the forces they will encounter without failing. This grading system considers the material's ability to resist bending, which is critical for maintaining structural integrity.

While posts are vertical members that support beams and have a different set of size and strength requirements, frames typically refer to structures formed by various interconnected components rather than singular support elements. Planks, on the other hand, generally indicate flat, wide boards used for flooring or decking, which do not fit the specific criteria of thickness and grading mentioned. Thus, "Beams and stringers" is the most accurate answer.