Decision-making (DM) at the early building design stages is essential to optimise sustainability performances. Nevertheless, the current methods of optimising building sustainability are complex as they involve multiple design variables and performance objectives. With the development of building information modelling (BIM), complicated buildings can be digitally constructed with precise geometry and accurate information for design optimisation in the early stages of project. Thus, this study explores the use of BIM and Genetic Algorithm (GA) to support DM and optimisation for sustainable building envelope design. To develop a BIM-GA optimisation method, Autodesk Revit template was created to extract data of building envelope from a Base Model (BM). Then, the data were employed to compute overall thermal transfer value (OTTV) and construction cost for BM evaluation and GA optimisation. A hypothetical building was modelled and then analysed using the proposed method as a test case. The BIM-GA optimisation method can address the difficulties of DM on building sustainability in the early design process.
autodesk revit, decision-making, design process, optimisation, overall thermal transfer value
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