Understanding the components and magnitude of the cost of quality in building construction

Purpose

Though the components and concepts of cost of quality (COQ) are well understood in the domain of manufacturing, only limited data are available from the construction industry for various reasons. The present study seeks to establish a relationship between project defect score (pds), representing the quality of construction in the project, and the COQ in the building construction industry. The study also seeks to estimate the contributions of the various components to the overall COQ in the construction industry, along with their distribution and interrelationships among themselves.

Design/methodology/approach

A framework for estimating COQ was developed, and the data regarding prevention, appraisal and failure cost were collected from 122 projects. Various mathematical and statistical tools like Pearson's correlation, multiple linear regression (MLR) and curve fitting have been used for data analysis.

Findings

The prevention–appraisal–failure (PAF) model was found to be appropriate to estimate COQ, and the prevention, appraisal, conformance cost (CC) and failure cost were found to vary between 0.19 and 8%, 0.05 and 5%, 0.3 and 10% and 0.01 and 5%, respectively, whereas the overall COQ varied from 3.5 to 10.01% of the project cost. The correlations between various components of COQ were found to be significant. MLR suggested that appraisal cost is more impactful in reducing failure cost than prevention cost. Using curve fitting, the cubic model appropriately represented all interrelationships. The optimal overall COQ was found to be 3.86%, and the reasons for low COQ have been explored.

Originality/value

The study evaluates the applicability of available models for COQ calculations for the construction industry and presents a framework to estimate its components. The study also explores the interrelationship between the various components of COQ and presents a generalized relationship between COQ and the pds.