2304.10.1 Minimum Member Sizes

Columns shall be at least 8 inches (203 mm) in all dimensions when supporting floor loads and at least 6 inches (152 mm) wide and 8 inches (203 mm) deep when supporting roof and ceiling loads only.

Beams and girders shall be at least 6 inches (152 mm) wide and 10 inches (254 mm) deep.

Frames and arches that spring from grade or the floor line and support floor loads shall be at least 8 inches (203 mm) in all dimensions. Frames or arches for roof construction that spring from grade or the floor line and do not support floor loads shall have members at least 6 inches (152 mm) wide and 8 inches (203 mm) deep for the lower half of the height, and at least 6 inches (152 mm) deep for the upper half. Frames or arches for roof construction that spring from the top of walls or wall abutments, framed timber trusses, and other roof framing, which do not support floor loads, shall have members at least 4 inches (102 mm) wide and 6 inches (152 mm) deep. Spaced members may be composed of two or more pieces at least 3 inches (76 mm) thick when blocked solidly through their intervening spaces or when such spaces are tightly closed by a continuous wood cover plate at least 2 inches (51 mm) thick secured to the underside of the members. Splice plates shall be at least 3 inches (76 mm) thick. When protected by approved automatic sprinklers under the roof deck, framing members shall be at least 3 inches (76 mm) wide.

Timber trusses supporting floor loads shall have members at least 8 inches (203 mm) in all dimensions.