Patented in the 1880s and having a longstanding industrial history, expanded metal sheet has a remarkable reputation for its application. However, despite the benefits of its use and numerous studies has been conducted on window shading and its daylight evaluation, research on extended metal shading’s daylight performance is still limited. This paper investigates the role of expanded metal shading to assess Daylight Glare Possibility (DGP) in Shimonoseki, Yamaguchi, Japan, utilizing parametric design approach and Multi-Objective Optimization (MOO). The simulation and analysis were undertaken to determine how expanded metal can optimize DGP, the significance of improvement, the relationship between the View (aperture) and the DGP, and which parameters have the most influence in driving the aperture size and the DGP value. Analyzing 2322 solutions and 88 Pareto frontiers resulted from the MOO, several findings has been portrayed. Firstly, the shading View (aperture) shows a significant positive correlation to the DGP. Secondly, parameter Strand/W was identified as the most influential parameter that drive the objectives. Thirdly, the validation process portrays optimization in DGP by 38%. The results of the proposed methodology are expected to become an immediate geometry and performance feedback for designers and industries, supporting design decision-making processes during early design phase.