Evaluating coupled embodied and operational carbon performance of common floor slab systems in China

The selection of building components, a fundamental yet often routine design decision, plays a pivotal role in shaping a building’s life cycle carbon emissions. Existing research has largely focused on embodied carbon (A1–A5) of construction materials, overlooking how these choices interact with operational carbon (B1–B7) and recycling potential (D) over the building’s service life. This study addresses this gap by applying an integrated life cycle carbon assessment approach that links embodied and operational stages to evaluate three widely used floor slab systems in China: Cast-in-place Reinforced Concrete Floor Slabs (CRCFS), Gypsum Block Mold Hollow Floor Slabs (GBMHFS), and Precast Laminated Floor Slabs (PLFS). Distinguished from existing studies, this research establishes a high-resolution inventory dataset based on quantitative Bill of Materials (BoM) from real-world engineering projects. Using a process-based life cycle assessment with 1 m² of slab as the functional unit, we quantify both stage-specific and cumulative carbon emissions under equivalent structural performance. Results reveal that PLFS and GBMHFS achieve 9.68% and 5.38% lower embodied carbon emissions than CRCFS, respectively, while also reducing operational energy demand by 7.42% and 3.48% over a 50-year service life due to improved thermal performance. By defining a comprehensive system boundary of (A1-B7) + D, this study integrates a quantified BoM with parameters anchored in relevant standards and policy documents to establish a verifiable and reproducible workflow, thereby providing transparent data for typical Chinese floor slabs. This work contributes to the growing body of research on component-level carbon optimization by demonstrating how thermal and structural properties of floor slabs jointly affect life cycle emissions.