Recent studies increasingly offer new Building Information Modelling (BIM) solutions and some other studies are modelling BIM adoption and implementation practices. However, the migrating process from the current practice of using desktop-based BIM to a web-based BIM covering broader activities of the entire project lifecycle is complicated. This paper intends to develop the migrating process including main factors that inhibit higher level of web-based BIM usage (e.g. digital autonomous online systems) at construction companies. A case study approach is utilised to collect rich data from three contractors that provided best practices of using BIM in Sydney, Australia. The result of the study shows that there are ?challenges? that hinder pragmatists to migrate from lower level BIM usage to higher level BIM implementation at the construction companies. The key challenges of higher level of BIM usage from contractors? point of view can be divided to technical and managerial challenges. Technical factors include availability of internet infrastructure for web-based BIM and compatibility with other available technologies. Managerial challenges include possibility of changing engineering procedure within contractor?s organisation and availability of expert and low skill workers. The study contributes in the body of knowledge by deepening understanding of challenges of BIM implementation for conservatives, which may follow pragmatists in adopting more advanced technologies. The results of the study help the industry policy makers who encourage contractors to use higher level of BIM by resolving the challenges and provide more supportive resources or infrastructure for contractors to cope the challenges. The study will expand to investigate more contractors and other AEC companies to continue to uncover more in-depth challenges. Future recommendations include comparing both the levels and types of challenges faced in different countries. The result can be generalised if many other cases investigated across the country. The study will be extended by focusing on infrastructure projects using more interviews, and developing a roadmap to facilitate the target in each country for web-based BIM implementation.