Quantifying the environmental impacts and simulating the energy consumption of building’s components at the conceptual design stage are very helpful for designers needing to make decisions related to the selection of the best design alternative that would lead to a more energy efficient building. Building Information Modeling (BIM) offers designers the ability to assess different design alternatives at the conceptual stage of the project so that energy and life cycle assessment (LCA) strategies and systems are attained. This paper proposes an automated model that links BIM, LCA, energy analysis, and lighting simulation tools with green building certification systems. The implementation is within developing plug-ins on BIM tool capable of measuring the environmental impacts (EI) and embodied energy of building components. Using this method, designers will be provided with a new way to visualize and to identify the potential gain or loss of energy for the building as a whole and for each of its associated components. Furthermore, designers will be able to detect and evaluate the sustainability of the proposed buildings based on Leadership in Energy and Environmental Design (LEED) rating system. An actual building project will be used to illustrate the workability of the proposed methodology.

Many construction projects suffer from poor design and from inconsistent time and cost management. This situation has led to rethinking of the industry’s performance and how it could be improved. Technology is breaking through design and management practices. Earned value management (EVM) enables better management of time and cost constraints. Building Information Modeling (BIM) is recognized to improve the planning and realization of a construction project. The present paper proposes an integrated time and cost management system (ITCMS), where an EVM platform is used in a virtual environment during the planning and construction phases of a project. The ITCMS enables early involvement and project integration plus thorough time and cost management. The system consists of four modules and 13 different processes. The ITCMS is beneficial at the design stage; construction professionals are able to synchronize the building model with time and cost parameters as well as optimize it through a clash detection process that results in budget and schedule compressions early on. The ITCMS is a useful tool for construction and engineering managers that strive to increase projects’ performance. The authors demonstrate in this paper the validity of using the ITCMS through an actual project.

Owners, architects, and engineers are highly concerned about the sustainability and energy performance of proposed buildings. Evaluating and analyzing the potential energy consumption of buildings at the conceptual design stage is very helpful for designers when selecting the design alternative that leads to a more energy efficient facility. Building Information Modeling (BIM) assists designers assess different design alternatives at the conceptual stage of a building life so that effective energy strategies are attained within the green building constraints. As well, at that stage, designers can select the right type of building materials that have great effect on the building's life cycle energy consumption and operating costs. The aim of this paper is to propose an integrated method that links BIM, energy analysis, and cost-estimating tools with the green building certification system. The successful development of the proposed method helps owners and designers evaluate design alternatives, taking into consideration the sustainability constraints in an efficient and timely manner. BIM's tool is customized to allow its integration with the energy analysis application to identify the potential gain or loss of energy for the building, detect and evaluate its sustainability based on the U.S. or Canadian Green Building Council (USGBC or CaGBC) rating systems, and approximately estimate the costs of construction early at the conceptual design stage. An actual building project is used to illustrate the workability and capability of the proposed method.

To explore the differences in carbon emissions over the whole life-cycle of different building structures, the published calculated carbon emissions from residential buildings in China and abroad were normalized. Embodied carbon emission flows, operations stage carbon emission flows, demolition and reclamation stage carbon emission flows and total life-cycle carbon emission flows from concrete, steel, and wood structures were obtained. This study is based on the theory of the social cost of carbon, with an adequately demonstrated social cost of carbon and social discount rate. Taking into consideration both static and dynamic situations and using a social discount rate of 3.5%, the total life-cycle carbon emission flows, absolute carbon emission and building carbon costs were calculated and assessed. The results indicated that concrete structures had the highest embodied carbon emission flows and negative carbon emission flows in the waste and reclamation stage. Wood structures that started the life-cycle with stored carbon had the lowest carbon emission flows in the operations stage and relatively high negative carbon emission flows in the reclamation stage. Wood structures present the smallest carbon footprints for residential buildings.