Abstract: A structural panel (20) for a prefabricated building includes a plurality of spaced, generally side-by-side tubular columns (22-28), a header and a footer (36, 38) each interconnecting the respective ends (30,32) of the columns (22-28), and a plurality of spaced, tubular cross members (40,42) interconnecting the columns (22-28) along at least one of the column sides (34). In preferred forms, the panel (20) has two end columns (22, 24) and two intermediate columns (26, 28), and the cross members (40, 42) are arranged in pairs positioned on opposite sided (34) of the columns (22-28) in registry with each other. Each cross member (40, 42) runs generally transverse to the columns (22-28) and presents a length that is not less than the distance between the two end columns (22, 24). Advantageously, the tubular columns (22-28), header and footer (36, 38) and cross members (40, 42) are comprised of sheet metal formed to present a generally rectangular cross section.