As amazing its appearance is, spiral stair has complex geometric configuration. As a result ofrnthis complexity, its analysis is challenging. And our Building Code of Standard doesnâ€™t havernanalysis aid for these special structures, like the ones we have for slabs. Hence, the purpose ofrnthis study is to come up with a convenient and user friendly analysis tables and charts for thernanalysis of spiral stairs. This research follows analytical and finite element approachrninterdependently. The out come of the research is perceived by accompanying the comparativernassessment of the two approaches.rnThe analysis of spiral stairs is done in different approaches. First detail formulation is derivedrnfor the stair using strain energy concept considering the stair as twisting girder and in planerncurved beam. Secondly, modeling and analysis is carried out using finite element technique asrn3D twisting beam and 3D twisting shell stair slab separately. Then, graphical and tabularrncomparison is done between all approaches. In addition, modification factors are formulatedrnconsidering variation of internal actions along stair width. More over, valid width is demarcatedrnto limit the acceptable width for the applicability of centerline model for stain energy solutionrnof helical stairs.rnHence, the analysis tables and charts that are annexed in the write up together with thernmodification factors presented are very crucial tools for the analysis of these spectacularrncomplex structures.