Abstract: A frame or chassis for mobile homes and the like provides a pair of laterally spaced, parallel I-beams extending the length of the frame. Wood floor joists are mounted on top of the I-beams and extend laterally beyond the I-beams in both directions. One-piece uniriggers having substantial tensile strength but relatively minor column strength in compression are connected to their ends directly or indirectly to the ends of the floor joists. The uniriggers provide outrigger portions extending downwardly and inwardly to the adjacent I-beam and a cross member portion extending laterally between the I-beams. The uniriggers are welded to the bottoms of the I-beams and cooperate with the associated floor joist to provide a trusslike structure which prevents rolling action of the beams. The frame or chassis provides adequate strength and rigidity when the frame is being supported by wheels and axles for road transportation and also when the frame is supported at intervals around its periphery at a use location.