A case study of cost of quality in architectural works in a condominium construction project

Abstract

A high-rise condominium construction project is usually costly with complicate details of the interior decorations and requirements in aesthetic and functional from buyers of each unit. The requirements affect the inspections and commissioning of each unit and can result in higher cost of quality to the developer. This study aims to determine the failure costs due to reworks of architectural works in a condominium construction project. Architecture rework orders of a 46-story condominium construction project with 554 units, and starting price of 3.99 million baht per unit, were categorized into five main categories, i.e., Floor, Wall, Ceiling, Door & Window, and Sanitary-Ware. The 80/20 Pareto analysis was used to identify 12 major defects. That collectively resulted in 80% of rework orders. The Wall category was found to have the highest number of rework orders, composed of 22.34% of plaster wall defects and 15.23% of wall corner defects. Among the plaster wall defects, 34.08% of the defects are cements finishing defects, while 20.87% of wall corner defects were due to vertical alignment of the wall corner (20.87%). Overall, rework orders of architectural works were issued in 420 units (75.81%). The reworks were carried out in batch of works in the same category and were not carried out by individual order or by unit. With this batching rework approach, the time it takes to close out the rework orders, were prolonged, and commissioning were delayed, resulting in higher cost of quality.