This study investigates the effectiveness of Vertical Seismic Isolation (VSI) in enhancing structural response under seismic loading. Unlike conventional base isolation, which separates the structure from the ground horizontally, and adjacent building systems that use dampers between neighboring structures, VSI vertically decouples a structure’s mass and stiffness components using an intermediate damper. This configuration aims to control vertical energy transmission within the structure itself. A simplified model is developed with equal isolation factors for mass and stiffness, ranging from 0.1 to 0.9. State space analysis is used to evaluate the seismic performance of a single-degree-of-freedom system subjected to various ground motions. The system incorporates two damper types: nonlinear viscous and viscoelastic. Numerical analysis of acceleration and displacement responses reveals that both dampers significantly reduce seismic effects, with nonlinear viscous dampers showing superior displacement reduction under intense seismic activity. Optimal damping coefficients and isolation factors are identified to maximize effectiveness. The study concludes that VSI is a viable and efficient alternative to traditional isolation strategies, offering improved seismic resilience through optimal tuning of damping parameters and isolation factors.