Assessment of Carbon Neutrality Performance of Buildings Using EPD-Certified Korean Construction Materials

Achieving carbon neutrality in the building sector is essential for addressing the global climate crisis. However, the production stage—which contributes to over 29% of a building’s life cycle carbon emissions (CE)—poses significant challenges for consistent carbon performance assessment due to the diversity of building materials and the uniqueness of individual building projects. These factors often lead to inconsistent evaluation results across assessors and the fragmented management of carbon data at the project level. This study proposes the Zero Carbon Building Index (ZCBI), a quantitative assessment method that incorporates embodied carbon from raw material extraction, transportation, and manufacturing. ZCBI enables the evaluation of carbon neutrality performance at the material level and supports the identification of reduction potentials in the production stage. A classification system was developed to evaluate CE during production, creating reference buildings for residential and non-residential purposes. Additionally, a Korean Environmental Product Declaration (EPD) database was established by incorporating CE data from 797 EPD-certified materials. Carbon reduction (CR) and ZCBI values were analyzed by categorizing CE variations across manufacturers into the lowest, average, and highest values. The results showed that CR for apartment complexes ranged from 42.1 to 311 kgCO2e/m2, with ZCBI values between 8.84% and 65.30%, and those for business facilities ranged from 40.9 to 264 kgCO2e/m2, with ZCBI values from 8.59% and 55.43. The proposed ZCBI framework provides a basis for optimizing material selection to reduce emissions and may evolve into a comprehensive carbon neutrality assessment covering the entire construction process.