This study examines the use of granular soils mixed with tire derived aggregates (TDA) as an underlying soil layer for surface foundations. The benefit of this geotechnical seismic isolation (GSI) scheme is threefold: the seismic force and displacement are significantly reduced; the construction is similar to that of a regular compacted granular fill and the re-use of scrap tires has an assertive environmental impact. These features highlight the rubber/soil mixtures (RSM) as a promising seismic isolation technique for infrastructure and large-scale structures. The seismic isolation capabilities of a rubber-soil foundation layer are investigated, using well defined material properties, and the direct analysis method of the soil-structure system, in the form of a simple oscillator on a soil profile. The influence of the RSM layer on the fundamental variables of the seismic response, namely the base shear and the total drift displacement of the structure on deformable soil, is examined. The structure′s overall stability is studied by means of monotonic lateral load analysis and incremental dynamic analysis, varying the slendess of the structure and the synthesis of the mixture. The effectiveness and capabilities of the RSM isolation scheme are presented and discussed.