Abstract—Diagrid exoskeleton structures have recently come to the forefront as a possible asset for an integrated remodelling strategy for existing buildings, where structural safety, energy efficiency, environmental sustainability, and architectural excellence are all enhanced. This research study examines the seismic performance of diagrid structures and their capacity to dampen earthquake-induced vibrations while considering a module set and member sizing methodology. This methodology considers the influence of the diagonal angle on the behaviour of the diagrid system under seismic loading. The models are created and analysed using general purpose FE software, ABAQUS. The models’ nonlinear finite element analysis is broken down into different phases. In the first stage, the FEM is subjected to response spectrum testing with the goal of comparing their performance under earthquake. The second stage is the response spectrum test, allowing structural safety to be determined. In addition, the Peak Floor Acceleration (PFA) at various floors is determined using a mode superposition approach. The results show that, in addition to displacement and deformation control, significant reductions of the internal forces in the exoskeletal system are observed.