Research shows that the precast construction process comprises waste and excessive lead times. The application of Lean Construction principles within the precast construction process varies from one country to another due to different regional codes, market demands, informatics tools, fabrication and erection methods, etc. This paper deploys value stream mapping (VSM) as a lean methodology to investigate and compare the process differences between a Canadian precast project and a Chinese precast project as a basis for improvements in reducing process waste. A framework of comprehensive future state mapping is proposed based on the application of advanced technologies advised by industry 4.0 to guide future precast projects towards a lean process value flow.