Comparison of Safety and Sustainability of U-Shaped Internal Staircase Projects via a Combined MCDM Approach CORST

Abstract

Properly designed and installed interior stairs provide safe and convenient access to all residents of the house, including children and elderly people. While safety considerations are paramount for stair design and placement decisions in a two-storey single-family house, sustainability becomes another important factor in these deliberations. Nevertheless, safety and sustainability of the interior stairs can be seen as conflicting objectives in decision-making processes (i.e., while a larger staircase area positively affect residents’ climbing ability, it also causes higher energy consumption and material usage). Therefore, increased awareness of stair-project selection processes is required when multi-objective tasks are involved. Seven criteria affecting stair safety and sustainability in a single-family house are identified in this paper. The integrated AHP-MEREC criteria-weighting approach is proposed, to determine their weights in decision-making processes. Four different multi-criteria decision-making (MCDM) approaches, ARAS, SAW, TOPSIS and PROMETHEE, were used to determine alternative evaluations. Since the selection of the most suitable MCDM method is full of uncertainties, the novel combined-decision-making approach formally called CORST (COmbining MCDM appRoaches using method STability coefficient) is proposed in this paper. The new method stability coefficient is used to determine the stability and reliability of the specific MCDM approach. Nine U-shaped inside-staircase projects dedicated to a single-family house were evaluated, to test the effectiveness of the CORST approach.