As a core structure for laminar flow control suction panels, triply periodic minimal surface structures are exposed to mechanical loading and must guarantee sufficient internal airflow and pressure drop control. While their mechanical properties depend mainly on their relative density, their aerodynamic properties depend on their surface-to-volume ratio. This chapter introduces design methodologies for triply periodic minimal surface sheet networks. It characterises their relative density and surface-to-volume ratio based on their geometric design parameters, wall thickness and unit cell length. This chapter presents equations for the relative density and surface-to-volume ratio of Gyroid and Primitive sheet networks, derived from analytical equations for regular hexagonal honeycombs. In combination, these equations show that both TPMS structures allow the adjustment of the relative density and the surface-to-volume ratio independently and, therefore, allow the separation of the mechanical and aerodynamic design. However, only the Gyroid structure consistently achieves an open channel network at high relative densities across different design methodologies. Therefore, the Gyroid structure is further investigated for implementation in laminar flow control suction panels.