The increasing request for energy-saving and saving materials and growing concern related to the impacts of materials used on environmental and economical has driven the construction industry toward redesigning critical structural systems and elements. This research proposes solutions for mitigating ecological effects and sustainable built environments. For example, the floor slab is considered the top environmental impact emission after walls compared to other non-load-bearing elements among different building components. Therefore, this research expands the new slab comprising Glued laminated timber (GLT) with concrete as a novel lightweight flooring system. The related methodology includes life cycle assessment (LCA) and life cycle cost (LCC) analysis. Thus, the environmental and economic impacts of three common slab systems were compared to the proposed slab. The evaluation results revealed that GLT-concrete has lower emissions in all environmental categories, namely: Global warming potential (GWP), Eutrophication Potential (EP), human toxicity potential (HTP), fossil depletion potential (FDP), terrestrial Ecotoxicity (TE), and Acidification Potential (AP). Likewise, Embodied energy value showed that GLT-concrete has a lower value by 26%, 9%, and 24% than Lightweight steel slab, Precast reinforced slab, and Cofradal slab. Finally, the result of LCC shows a new GLT-concrete slab despite having a higher construction cost, but by considering the end of life scenario as reuse, it will have a lower total cost. Thus, current research can expand the assessment of environmentally friendly floor structures and step toward sustainable construction.