Most of the research on seismic retrofit approaches focuses on the development of innovative retrofit solutions with the aim to improve the seismic performance of existing buildings through either local or global strengthening. An effective alternative approach is controlling the seismic performance of existing buildings through the selective weakening of specific portions of the structure, particularly to reduce stiffness irregularities. The present research focuses on a possible weakening approach dealing with the transformation of the existing columns of a given storey, specifically at the ground level, in rocking columns. This solution will lead to a global behaviour like the one of an isolated system. The advantages of such a solution are, among others: the reduction of the relative displacement demand at the storeys above the rocking system (i.e., damage reduction at the upper storeys), the damage in the rocking columns would be limited and controlled through confinement, the construction works would be lumped at just one storey, the rocking columns can be coupled with an additional energy dissipation or recentring system. The effectiveness of the proposed solution has been evaluated through the application to a reference case study.