Large and important structures are designed for seismic loads, in addition to the other loads such as dead load, superimposed dead load, and live load. For the purposes of structural analysis, the seismic loading at the base of the foundation is represented either by the response spectrum or by the time history of excitation. The seismic excitation travels from the bedrock to the bottom of the foundation through the intermediate soil media. Variations in soil stratification and the properties along depth impact seismic wave transmission, and alter seismic excitation at the base of a structure. Moreover, bore logs from diverse locations beneath a foundation reveal the spatial differences, and hence seismic excitations reaching the base will be affected. When analyzing buildings, typically a single ground motion input is used even under multi-support excitation conditions, due to complexity in analysis or lack of detailed information on ground motion beneath each foundation unit. For safe structural and geotechnical design, the variability in ground response needs to be appreciated. In this study, bore log data from a site is adopted to demonstrate the range of variability in ground response that might arise due to the soil stratification. DEEPSOIL® [1], a one-dimensional finite element (FE) tool, was employed to simulate seismic wave propagation from bedrock to foundation base. Multiple models representing various observed soil stratifications were developed, and seismic ground motion data from similar sites were used to examine variability of the ground response. The case study illustrates the ground response variability for a typical site.