AbstractThe selection of materials for a sustainable building façade has various requirements, which include the analysis of economic performance, as well as the physical performance at every stage of their life cycle. Previous research efforts have focused on buildings and building systems in terms of critical issues of life cycle cost (LCC). Concomitantly, little research has been reported on calculating the LCC of façade material for a building at the design stage; LCC is a critical issue in the selection of facade materials. In particular, investments in long-life elements, such as building façade materials, are characterized by uncertainties regarding service life, operation and maintenance costs, revenues, and other factors that affect project economics. Therefore, it is essential to review uncertainties affecting these variable factors in computing LCC. This research aims to develop a process for calculating the probabilistic LCC of building facade materials throughout their life cycle. The research method includes life cycle cost analysis (LCCA) and failure mode, effect, and criticality analysis (FMECA) as research methodologies. Thus, the original contribution of this research is the development of a probabilistic LCC assessment within the decision-making process of selecting optimal facade materials of buildings at an early stage. The case study shows that with new, closer replacement cost estimates based on a probabilistic approach, the uncertainty could be reduced, and the confidence index (CI) improved; the alternative with a lower LCC may be implemented with reasonable assurance that it will have the lowest costs over its lifetime.