FUZZY EXPERT SYSTEM TO ESTIMATE THE COST OF QUALITY IN RESIDENTIAL CONSTRUCTION PROJECTS

Although the concept of the cost of quality (CoQ) is not new, earlier research focused on the direct costs of quality management, such as those associated with prevention, appraisal, and failure (PAF approach). The new ISO 9001-2015 edition has presented a new idea based on the risk approach rather than the process approach, which means that project risks have a crucial role in quality management and hence in the calculation of the CoQ. A prototype fuzzy expert system model is introduced in this study to calculate the optimum CoQ while taking project risks into account. The weights assigned to each CoQ component as well as the quality risks were gathered from previous studies and verified through formal surveys and interviews. The risks affecting CoQ include inadequate planning, communication and coordination failures, construction errors/omissions, and delays. The CoQ was found to be about 3% of the project budget. The prototype fuzzy expert system was validated with an accuracy of 96%.