BIM-based approach for Estimating life cycle costs of building in conceptual design phase using Iran's national price list

All costs within the life-cycle of a building are known as its life-cycle costs. In the design process of a building, the use of a lower initial cost index to select an option among others with similar performance may not lead to an economically optimal choice during the life-cycle. Hence today, building designers and investors require a tool to estimate life-cycle costs at the conceptual design phase to elect an economically-efficient option. The purpose of this study is to provide a framework to estimate life-cycle costs of a building at the conceptual design phase based on building information modeling. For this purpose, the costs of the building's life-cycle, including initial costs (cost of supply and installation based on Iran's national price list and shipping costs), repair and maintenance costs, operating costs (energy consumption) and salvage value at the end of the building’s useful life are regarded in the estimation of its life-cycle costs. The application of the proposed framework was then evaluated and approved for designing a residential building in Tehran. The application of the proposed framework for designing a residential building in Tehran was assessed and validated on two modelsو and the results showed that by increasing the initial costs in the second model by 75%, its annual operating costs decreased by 54% and Total life-cycle costs have dropped by 8% after 18 years. In this way, building designers can estimate the life-cycle costs of a building at the incipient stages of design and improve its design.