Comparative Life Cycle Assessment of Elastomeric Bitumen and Polymer Modified Bitumen Emulsion for Waterproofing Systems Based on Primary Data

Increasing attention to environmental performance in construction materials has intensified the need for robust Life Cycle Assessment (LCA) studies on bituminous waterproofing systems. This study addresses the lack of comparative LCAs based on primary data for hot-applied Elastomeric Modified Bitumen (EMB) and cold-applied Bitumen Emulsion (EMBE), two widely used materials with contrasting application methods and environmental profiles. While EMB has been moderately covered in the literature, this study contributes uniquely by providing one of the first LCAs based on primary data for EMBE, a formulation that is increasingly adopted in the construction sector but still underexplored in environmental assessments. The primary industrial data were combined with international LCI datasets (Ecoinvent) to model environmental impacts using SimaPro 9.4.0.3. Results show that EMBE demonstrates better climate performance (611 kg CO2 eq/t) but is more sensitive to specific additives, especially resins and plasticizers, which significantly increase Ozone Depletion Potential and photochemical ozone formation. The Environmental Product Declaration (EPD) survey analysis further highlights the influence of recycled content, cold mix technologies, and production energy sources on environmental performance. The findings indicate that the selection of waterproofing materials should consider not only technical performance but also the distribution of environmental impacts across the life cycle.