Lean Design Management – An Evaluation Of Waste Items For Architectural Design Process

Waste is standing as a major problem in the body of construction industry. Lean thinking in construction accepts any inefficiency as waste which results with more usage of equipment, materials, labour, time or capital in larger quantities than those considered as necessary. Although inefficiency of design stages has been identified as a major factor that reduces the efficiency of construction projects, less attention has been paid on the relationship between lean thinking and architectural design process. Thus, this study focuses on lean wastes of architectural design sector by considering the importance of addressing the problems of the operation in order to eliminate the inefficiencies. In this respect, as the first stage, “8 Waste” categories of “Lean Production Philosophy” and their reflections on architectural design service processes were examined.  28 Waste items under 8 categories were determined in the body of architectural design process as a result of semi-structured interviews conducted with senior architects performing in Ankara, Turkey. In the second stage, a questionnaire was executed over a larger population of architects to examine the  “frequency of occurrence”, “impact over cost”, “impact over duration”, and “impact over quality” for each design waste item. The research aims to provide information for the architectural design sector to increase the efficiency of their processes. The statistical analysis of the questionnaires shows that there is a shared understanding of impacts of waste items over architectural design processes, with strong statistical evidence over their validity.