One of the challenges in sustainability analysis and its development is the optimum selection of sustainable materials to meet the project's requirements while doing sustainable design. This can only be achieved when project team adopt the use of a strategic approach while selecting the materials, although this could be a complex task for decision makers. Building Information Modeling (BIM) offers designers the ability to assess different design alternatives at the conceptual stage of a project. As a method of integration and through its modeling techniques, BIM can be used to assess the impacts of design alternatives on the energy saving of buildings all over their life. Furthermore, BIM has the potential to help designers select the right type of materials during the early design stage, and make vital decisions when selecting the materials that have sustainable impact on the building's life cycle. The main purpose of this study is to propose a methodology that integrates BIM with decision-making problem-solving approaches (i.e. Entropy-TOPSIS) in order to efficiently optimize the selection of sustainable building components at the conceptual design stage of building projects. Therefore, a Decision Support System (DSS) is developed by using Multiple Criteria Decision Making (MCDM) techniques to aid the design team decide on and select the optimum type of sustainable building components and design families while doing conceptual design of proposed projects, based on three main criteria (i.e. environmental factors, economic factors-"cost efficiency," and social well-being) in an attempt to identify the influence of design variations on the whole building's sustainable performance. The multi-criteria procedure embedded in the DSS relies on numerical models to simulate alternative situations, as well as ranking the alternatives and select the best ones based on both the owners' strategic preferences and the availability of sustainable materials in the market. The set of models included in the DSS describes the relationship between sustainability criteria, manufacturers' sustainable materials and the interactions between project team that take place during the design of sustainable building projects. This paper aims at exposing the feasibility of using BIM for analysing the life cycle costs of sustainable buildings at the conceptual stage. The design alternatives suggested by the DSS are evaluated in an integrated environment that joins BIM concept and Life Cycle Cost (LCC) method to analyze the operational cost of the whole building. An actual building project is used to validate the workability and capability of the proposed methodology.