Building information modeling (BIM) is deemed a useful innovation for technological and sustainable development of the economy. It is partially used in building projects in Singapore, although its implementation is mandated by the local government, resulting in various wastes and suboptimal productivity. Little is known about how non-value adding (NVA) BIM implementation practices were perceived by the local practitioners and how these practices affected productivity in building projects in Singapore. This study aimed to identify critical NVA BIM implementation activities and investigate the criticality of their resulting wastes to productivity performance in the current project delivery process in Singapore. The results from a questionnaire survey of 73 experts and four post-survey interviews in Singapore revealed that 38 NVA BIM implementation activities were deemed critical, among which "lack of involvement by contractors to contribute site knowledge" in the design development phase was ranked top; the top five resulting wastes with highest criticalities were reworks/abortive works, requests for information, design deficiencies, defects, and waiting/idle time. Furthermore, an independent-samples t-test was conducted to examine whether construction firms and upfront stakeholders perceived the NVA activities differently. It was discovered that most NVA activities exerted more agreement from construction firms than upfront non-construction organizations. Six strategies were proposed to mitigate the NVA activities and wastes. The findings can help practitioners identify weak areas of their BIM implementation practices and prioritize resources accordingly to eliminate the wastes and foster sustainability, as well as help overseas project teams, with minor adjustments, customize their own NVA BIM implementation activities and management strategies.