Quality cost of material procurement in construction projects

Material procurement constitutes a large share of the overall cost of construction projects. Understanding the factors influencing the cost of quality (COQ) in the procurement process could help identify opportunities for lowering quality cost without compromising quality. The paper aims to discuss these issues.

In this paper, a COQ model for the construction material procurement process is developed using the traditional prevention–appraisal–failure (PAF) approach. Using data from a $4bn aluminum smelter construction project, the authors conducted a simulation of the COQ model to evaluate various quality assurance policies.

This paper confirms that raising the prevention cost leads to a drop in failure cost as well as COQ for the project studied. While the authors are unable to provide blanket recommendations as the results are derived from a single project case study, it does suggest that construction material procurement processes would benefit from a higher prevention expenditure. And for certain cases where the authors observe a deviation from the traditional Juran’s model of COQ – the high appraisal cost in the procurement process – reduction of appraisal expenditure may in fact be more beneficial than its increase.

The research results suggest that appraisal expenditure should be tailored to each purchase order in order to maximize the total benefits. Additionally, this paper presents the first COQ model developed for the construction material procurement process. Another unique feature of the model is its inclusion of supplier-side costs, which are excluded in the conventional COQ analysis.