A ladder including a first stringer and a second stringer spaced transverse from each other is provided. Each of the first and second stringers defines a channel and includes a plurality of crosspieces disposed in the channels of the first and second stringers. A plurality of rungs are spaced along and coupled between the first and second stringers. Each of the rungs has a horizontal portion and a vertical portion extending from the first stringer to the second stringer. A plurality of ribs are spaced along and coupled between the horizontal and vertical portions of the rungs.
