An alternate (simplified) procedure can be used to determine the base shear, V, and story forces, F_x, for low-rise, ìstandard occupancy,î light frame wood structures that are 3 stories or less in height (see UBC 1629.8.2, 1630.2.3, and Table 16-K):

This simplified procedure eliminates explicit consideration of the natural (fundamental) period of structural vibration, T, and the height to each floor level, h_x, when calculating base shear, V, and story forces, F_x. Furthermore, the extra force at the top of the structure, F_t, for approximating the effects of complex structural vibrations is not considered in the simplified methodology.