In an epoch defined by an increasing emphasis on environmental sustainability, the construction industry stands at a crucial juncture, where innovation and informed decision-making are imperative. This study investigates the intricate interplay between structural design parameters and environmental sustainability in concrete slab construction. Focusing on span length, live load variations, and the inclusion of secondary beams, this study seeks to establish a delicate equilibrium for achieving optimal structural efficiency while minimising the environmental impact. Analysis of span length reveals, as would be expected, that the minimum slab thickness meeting the deflection criteria increases proportionally with span length, demanding careful consideration in project-specific scenarios. Live load investigations highlight the sensitivity of slab design to external loading conditions, with increased live loads correlating with greater demand for steel reinforcement, deflection, and minimum slab thickness. The inclusion of secondary beams, while consistently reducing the required reinforcement and enhancing the deflection performance, has a marginal impact on the embodied carbon. This research contributes to the growing knowledge at the intersection of structural engineering and sustainability, guiding decision-makers toward informed choices for optimised, environmentally conscious structural solutions in the construction industry.