This research represents the final phase of a comprehensive study on the structural behavior of roofing systems incorporating innovative 3D steel truss beams and structural glass panels, specifically designed to safeguard historical and archaeological sites. Recognizing the vulnerability of these cultural assets, often located in seismically active regions, the study establishes a robust design methodology to address both gravitational and seismic challenges. This approach has previously led to the development of efficient design charts, as detailed in earlier publications by the authors. Expanding on the roofing system, the study delves into the conceptualization and parametric design of the supporting structures, comprising steel variable-section truss portals and V-shaped columns. Following the optimization of the system’s performance under gravitational loads, the design methodology is applied to a case study, verifying its effectiveness in seismic regions through incremental analysis.