Comparison of the architectural design process quality between BIM and traditional design methods

Abstract

Quality in the construction industry requires meeting the requirements and needs of the designers, engineers, and contractors involved in the process, as well as satisfying the customer's expectations. Although quality standards and quality improvement policies are not as established as in the manufacturing industries, it is important for organizations in the construction industry to gain a competitive advantage by ensuring high quality and low costs. When considering construction quality, quality control of the productions and resources that take place during construction usually comes to mind. However, this approach does not include investigating and improving the root causes of quality problems arising from the planning and design processes. In addition, the fact that the control and improvement of quality problems that arise in construction projects are practiced during the construction phase prevents the quality problems derived from design and engineering errors to be solved at the design stage with lower costs and resources. There are also instances where a design defect cannot be corrected in construction at reasonable costs. For this reason, the understanding of quality in construction should be approached in two ways. First of all, product quality in construction is related to the effectiveness of materials, equipment and technologies used in the construction phase. Secondly, process quality in the construction industry is related to the organization and management methods applied during the design, construction and operation phases. The expectations of the stakeholders (i.e., building owner, designers, engineers and management and organization) involved in the architectural design process are different from each other, and therefore they consider different factors when evaluating the design process quality. In order for all stakeholders to develop a common understanding of quality, effective communication methods between stakeholders should be determined, feedback systems should be established, and all parties should be involved in the process from the very beginning of the project design. As a result, the design output, which is expressed in clear and effective project documentation, developed by receiving feedbacks and checked for constructability, ensures that the product reaches the expected quality. In traditional design methods, the design process is divided into sub-processes and the complex design process is tried to be facilitated. However, this division causes the design process to progress independently between disciplines and causes separation between design teams, creating problems in communication, collaboration and integration, which are very important for achieving design quality. Therefore, the adaptation of digitalization, integration and collaboration tools in the design process has the potential to provide solutions to the quality problems present in the design processes. The Building Information Modeling (BIM) method, which has been discussed since the 2000s to provide solutions to these problems, can be used as a tool to improve the quality of the architectural design process with its features such as involving all stakeholders in the design process, providing interdisciplinary integration and supporting information sharing. In this study, the effect of BIM adaptation on the factors affecting quality in the architectural design process is compared with traditional design processes, to conclude whether the use of BIM is a suitable method to improve the quality of the architectural design process. Within the scope of the study, it was decided to conduct a survey as a research method, with the anticipation that there will be a difference between the evaluation of the design process quality of the architects who use traditional design processes and BIM processes in current architectural design applications. First, by conducting a comprehensive literature research, architectural design process is defined in a structured manner and the differences between traditional and integrated design processes were determined. Then, BIM process was examined; the usage areas, maturity levels and benefits of BIM to the design process were explained. Finally, the factors that determine the quality in the design process were determined and the quality evaluation scales for the survey study were prepared by comparing these factors with the benefits of BIM. In order to evaluate the difference between traditional architectural design processes and BIM processes in the context of quality management concepts, these scales were determined as: (1) design requirements, (2) communication (3) drawing and specification control, (4) tools, methods and techniques, (5 ) design validation, (6) project team, and (7) management and organization. In the analysis of the data obtained from a total of 83 participants as a result of the survey conducted with BIM and traditional design process users, the focus was on the participants' evaluation of the quality factors in the architectural design processes and the relationship of these factors with the design process quality. The data obtained through the survey from the evaluations of 42 users of BIM and 41 traditional design processes, were analyzed with descriptive and statistical analysis methods. Before the analysis of the data, reliability analysis was performed on the scales and it was determined that the scales used in the questionnaire were reliable. To determine the relationships between the scales the correlation analysis is applied, the relationships between the factors affecting the quality of the architectural design process of the participants presents conformity with the findings of the literature review. For the comparison of the participant groups, descriptive analysis was first applied, the mean values of the evaluations were presented, and it was observed that there was a difference in the evaluation of the quality scales between the two groups. In order to determine the statistically significant relationships between these differences, t-test analysis was performed for independent samples. The results of the independent samples t-test analysis have presented statistical significance, which demonstrates that the architectural design process quality of the participants using BIM processes is higher than the traditional design processes. In particular, significant differences were seen between the two groups in the scales of tools, methods and techniques (μd = 2,14), design verification (μd = 1,97), drawing and specification control (μd = 1,91), communication (μd = 1,85), management and organization (μd = 1,20), and design requirements(μd = 1,15). It was observed that this difference was less effective at the scale of the project team (μd = 0,47). Within the scope of this study, these results indicate that the use of BIM improves the quality of the architectural design process.