Labor/Labour Productivity – Cumulative Impact (Part 14)

This is McLaughlin and McLaughlins Project Professional’s fourteenth posting regarding labor/labour productivity and disruption.  This contribution provides an overview of process alternatives that are extremely helpful and valuable for all stakeholders concerned with labor productivity and management.

The Subject Series regarding Labor/Labour Productivity and Disruption can be viewed here.

It is widely recognized that changed work (sometimes called change orders – assuming that the contract is changed as a result) may have a negative impact on field labor productivity (lower productivity).  The impact of multiple changes may be recognized or sensed.  The challenges are both timely recognition and demonstration of cause and effect.  The publications listed below are some of the more useful and valuable references related to this cause and effect dynamic.

An article and related study published recently in Construction Lawyer has some valuable information and analytical process guidance that is very useful when considering potential impact to labor productivity resulting from changed work.

The publications used in this post are:

The references above, in one way or another, address methodologies and approaches to recognizing and analyzing the impact to labor/labour productivity due to multiple or cumulative changed work events.

One of the most prominent authorities on this matter is William Ibbs, professor of Construction Management, Department of Civil and Environmental Engineering, University of California.  Among his notable contributions is a study that evaluates the impact to construction labor productivity verses the timing of the changes.  This study is addressed in the 2010 Cumulative Supplement cited above.  Dr. Ibbs has offered comments regarding productivity posts on this blog in the past.

Along with Long D. Nguygen, assistant professor , Department of Environmental and Civil Engineering , Florida Gulf Coast University, Dr. Ibbs has published an very useful article in Construction Lawyer (please see above citation).  This article discusses several variations to the classic measured mile analysis.  The discussion is in the context of analyzing the potential impact to field labor productivity associated with changed work.  With well presented example calculations, Dr. Ibbs and Dr. Nguygen demonstrate various methodologies for evaluating impact of changed work.

Should readers have an interest in contacting Dr. Ibbs regarding this article or other matters, he advised using his e-mail (

Project professionals should approach the issue of labor/labour productivity in an integrated manner.  Labor productivity must be integrated with other related aspects of program and project execution planning or forensic analysis.  In planning for these practices, consideration must be given to progress planning, labor/labour crew requirements, progress impacts and professional forecasts.  The managerial approach should include methods and Key Performance Indicators (KPI’s) that provide the feedback needed to detect and identify variances from the Project Management Plan baseline.  The references listed above will be useful in the planning, contracting, controlling and managing process.

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