실행 연구를 통한 BIM기반 개산견적 프로그램의 건축 클라이언트 의사결정 지원 영향 연구

Abstract

The building industry client plays the role as the initiator presenting needs and ordering a project while making critical decisions on program. The design phase is most important one in the life cycle of a building project given that critical decisions on space program, the level of quality and the boundary of budget are made. In particular, at this stage, economic factors such as predicted cost and available quality within it are considered as the priority, so it is essential to make decisions with accurate understanding and information on final outputs and relevant costs. However, clients without experience in similar building projects face lots of difficulty to understand products and relevant cost items given that communication between them and project practitioners is conducted by means of 2D drawings and paper-based bill of quantity (BOQ). As a way to solve this difficulty, research has been conducted on how to introduce instruments for enhancing understanding of clients, and thus supporting clients decision making. Building Information Modeling (BIM) has been mentioned as a method to this end. However, providing practical solution on BOQ is challenging to not only the client but also project practitioners given that cost estimation in the design stage remains asepcts to improve due to the limited available information at this stage. Research to investigate practicability and effectiveness has introduced AHP(Analytic Hierarchy Process) but this method is likely to have limitation in terms of validation on the accuracy of responses. This research introduced action research while collecting data on verbal expressions (surveys, interviews) and non-verbal expressions (expression and behavioral analysis) in order to investigate the influence of 3D BIM-based estimation method upon clients decision making. Three factors that are supposed to influence upon client decision making are identified as economy, stability, and aesthetics. 10 inexperienced clients are selected and two methods are presented to them: 2D drawings with paper-based BOQ and 3D BIM-based estimation method. As a result of the analysis, it is found that the 3D BIM-based estimation enables clients to understand cost items more accurately than 2D drawings and paper-based BOQ. It is expected that ungraded estimation software with user-friendly user interface would enables client to make decision accurately and rapidly.