Abstract In this study, we propose an integrated model for collaborative Construction Supply Chain (CSC) planning that deals with the joint project scheduling and material ordering decisions. The main objective is to achieve more coordination and, therefore, to reduce the total CSC cost. More specifically, we consider a two-echelon Supply Chain (SC) composed of a manufacturer, a warehouse, and multiple construction sites where multiple independent construction projects are planned. The projects require different materials that are provided by the same manufacturer with a limited production capacity. The starting time of each activity is subject to materials availability in construction sites. A mixed-integer linear programming (MILP) model is developed to reduce the total costs while collaboration between contractors is possible. The model is implemented using the IBM ILOG® CPLEX® Optimization Studio and used to analyze the collaboration process through a numerical study to demonstrate the benefits of collaborative planning in construction project management. The decision model help also in finding practical construction projects’ sequences as well as suitable materials ordering, manufacturing, and inventories plans for SC participants.