ABSTRACT
Structural engineers emerged as a separate profession during the late nineteenth and early twentieth centuries. Before that the geometry of stairs and ways of supporting them had evolved based on the dimensions of the human body, and experience. e structure was determined by traditional methods of employing timber, brick and stone, which were the commonly used structural materials. e nineteenth century saw the development of new and stronger structural materials, and the pace of change gave no opportunity for designs in these materials to be developed by trial and error. at led directly to the involvement of engineers in stair design, since their skills provided a means of designing stairs economically in new materials using mathematical calculations, which was quicker and cheaper than allowing new designs to evolve by rule of thumb. Sometimes these new materials were used simply as a direct substitute for timber or stone in a traditional structure, but they also o ered all sorts of opportunities for new forms and scales of structures, including stairs.
