A structure that has a permanent offset from a true vertical line is commonly referred to as being ‘out-of plumb’. Out-of-plumb may result from construction tolerances or post-earthquake permanent deformations in steel buildings. This paper quantifies the displacements of buildings with out-of-plumb in subsequent seismic events by means of inelastic dynamic time history analysis. Structures considered have different structural heights, force design reduction factors (R), and target inter-story drifts. It is shown that buildings with greater out of plumb and force design reduction factor have larger normalized peak inter-story drift ratio and ratio of residual-to-peak drift. Also, the ratio of residual-to-peak drift was not strongly dependent on structural height or design drift. A design procedure and example provided, based on the results obtained, show how peak and residual inter-story drift ratio can be estimated.
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