The grey model, which is constructed from the grey system theory, focuses on the insufficient information available, or the uncertainty of information that is [29]. It has been extensively utilized in the industries of finance, economics and the quantification of construction waste generation [30]. A major advantage of this method is that it can help predict problems with less **data** [29], which is extremely suitable for the current study. As the core of grey theory, the grey model (1,1) is a first-order linear differential equation of a single variable selected to forecast the generation amount of construction waste in Shanghai City in the next 10 years.