The fragmented nature of the construction industry, lack of supervision on the operational status of buildings after completion and complexity of scoring systems of some sustainability assessment tools are among the reasons that make the implementation of such tools in developing countries difficult. The aim of this paper is to introduce a new criteriabased sustainability assessment tool for residential buildings in Iran by considering the project management body of knowledge as a reference for developing categories and a guideline to define a framework for evaluating different phases of construction. The analytic hierarchy process is employed as a method of prioritisation of the sustainability criteria studied. All the criteria are categorised into five groups: resource management, quality management, environmental impacts management, zone management and risk management, in which they are assessed in the three phases of design, construction and operation. The unique features of the tool that distinguish this tool from others are: assigning the project manager as the sole authority to implement, monitor and control the sustainable assessment tool; simplicity of assessment method; cyclic evaluation of project after completion; incorporating a managerial approach towards solving the environmental problems; and phasic appraisal of construction works.