CONSTRUCTION PROCESS

Construction Process

Construction Process

Introduction

Production management is an integral part of the industrial construction process. The process lends itself to measurement by means of statistical tools - to help control the process. Reducing the variation or variability in a process is considered a sign of improved quality of the construction process. To quantify variability and distinguish the “vital few, trivial many” causes, control charts are used, that are constantly updated and communicated for timely feedback on process performance. Site-level experience on hundreds of projects suggests key construction performance measures include the variability and mean (average) percentage level of value-adding, productive work activity. The purpose of this paper is to submit that process metrics provides useful insight for constructing 'lean,' i.e., producing value efficiently. Measurement of the construction process involves statistical monitoring and analysis of value- and non-value-added work activities during project execution, using cost-effective random sampling of work activity combined with observation of the workflow.

Effective application of the technique of work process measurement and continuous improvement includes elimination of non-value-added activity and waste, and 'just-intime' manpower scheduling. Using the correct approach and the proper mindset, work process improvement is saving a major U.S. utility significant contractor labor cost on construction, plant overhaul and modification projects. Construction process sampling is a useful 'diagnostic' tool for understanding right action by management, supervision and workers alike - to optimize the work environment and create customer value at all times. Experience demonstrates that the quality of the tactical implementation of sampling is as important as the quality of the strategic planning of its use to transform the construction industry.

Discussion

The concept of production in construction - up to now mostly unfamiliar to the industry - provides new access to greater efficiency and effectiveness of the construction process. This paper conveys how the application of construction process measurement provides quantitative information to reduce variability - and thus reduce risk and cost to customer and society. As a rule, past practices and historical results dictate labor and time estimates for project completion. New planning tools or information technology to better manage construction may be helpful, but individually are incomplete - as is any strategy that fails to consider how variability of the complex, dynamic construction process affects project performance. It's not that managers are necessarily “old school.” The new tools often don't provide information they need for their own tasks (Drucker 2004, 65). Variability (and accordingly, uncertainty) is inherent in any process affected by people, equipment, work methods, management practices, and the environment.

The challenge is to understand the construction process and obtain useful information from it by measuring and quantifying its variability and level of performance. Koskela (2005, 85) put forward that production theory could explain the “inherent variability of production in construction.” On a macro level, there is much qualitative evidence of the link between variability and project performance, yet too few managers appreciate the importance of process variability - and manage it - in their immediate ...