This paper presents a theoretical model that can be used to create work-rest schedules for construction workers. Two objectives are proposed in the optimization processes when such schedules are created. These objectives include minimizing the time for completing jobs and minimizing any extra energy expended by laborers due to inappropriate work assignments that force them to work longer than the maximum acceptable work duration. A GA-based mechanism was developed to search the Pareto front, which is one of the effective ways for solving multiobjective optimization problems. Such a mechanism was implemented by computer programming using a numerical software tool called MATLAB. Theoretical examples demonstrated that the proposed model efficiently created work-rest schedules.