These parameters are the beam's allowable deflection, bending stress, and shear stress. This wood beam span calculator will focus on the first three parameters we typically test when designing a wood beam. Performing these calculations will help us choose the beam size and species that can support our anticipated loading and handle some unforeseen additional loading and natural weakening of lumber over time. We then adjust these design values to consider the long-term environmental and thermal effects mentioned above and see if the wood beam can still support the loading we anticipate it to carry.
Each wood species and grade has its own set of stiffness or design values, including bending stress, shear stress, tension and compression stresses, and modulus of elasticity. Other than the size of the beam, we also have a wide range of selection of wood species and commercial grade. We want to choose the size of lumber that can support the beam load we need to apply to it and can handle the effects of humidity and moisture, extreme temperature, bending, and shearing (to name a few). When choosing what size of lumber to use as a beam, we must consider various factors so we won't have a wood beam that can pose a danger to us.
