Implementation of the construction projects is associated with significant current material, technical and financial costs. They increase significantly in case of the breaking deadlines the large stages of projects and putting buildings into operation. The main aim of the current research is development the new approach for reliability model of the construction schedule for increasing reliability of the calendar planning regarding the meeting the construction projects on time. The following task were solved: the model of technical, labor and time reserves was developed; the algorithm of effective operational management system for the entire construction production process was offered. The probability of task completion was assessed by the E.M. Goldratt method, the probability function, based on the beta distribution was used. Initiating a shorter work execution period as a more stringent control action leads to an increase in the reliability of the construction program in the established settlement (contract) time from 50% probability to the normative 90% probability. Probabilistic approach allows to assess the achieved effect of applying the methodology of EM. Goldratt for the streamlined construction and to take a measured deadline for the execution of tasks in the development of the construction project.