Construction nonconformity assessment of buildings is critical to ensure the anticipated quality and living safety for their future occupants. Previous studies have paid less attention to identifying and analyzing building construction nonconformities (BCNs) in the design and construction (D&C) phases considering expert judgments, which are critiqued for human bias, uncertainty, and imprecision. In BCN assessment, previous studies also did not consider the specific time frame to detect construction nonconformities. This study aims to prioritize nonconformities in the D&C phases, addressing the limitations of expert judgment by applying the Fuzzy Group Decision-Making Approach (FGDMA). The FGDMA computes the This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers.