Lean Construction, developed by Glen Ballard and Greg Howell, is key to the concept of Cooperative Construction.  Lean Construction is essentially the elimination of waste. We mean all waste. Wasted time, resources, money, materials, labor and hundreds of categories buried in the complexity of large projects.  The tools developed to accomplish this difficult task, developed and fine tuned in elaborate detail by the Lean Construction Institute have a powerful impact and a curious personal nature to them.  In my book we research this personal nature in detail. Cooperation is the heart of the personal nature of these Lean processes. 

A recent book, This is Lean, by Niklas Modig and Par Ahlstrom, contains a forward by Greg Howell, one of my Giants, (upon whose shoulders I stand.) This is Lean describes an essential element of Lean Construction, called “Flow efficiency."

An extremely simple concept, Greg describes the significance of "Flow Efficiency" in the Forward.  Had he and Ballard known this concept, Greg says that the entire first few years of Lean construction would have been different. 

Essentially, the authors describe two kinds of efficiency: “Resource Efficiency” and “Flow Efficiency.”  Resource Efficiency is experienced constantly.  Simply standing in line generates Resource Efficiency.  The activity at the front of the line is being utilized at maximum efficiency, but The “Flow” has slowed to the speed of the function of the individual at the front to the line and the resource that they are utilizing. 

Flow Efficiency more complex system to develop as compared to resource efficiency.  Each person in line is called a “Flow Unit.” and the resource being accessed is being utilized at maximum efficiency. Adding resources might generate an inefficiency when the line dwindles. 

Of course, both Resource and Flow efficiencies need to be maximized and that is the work of the project staff at a construction site.  Historically, Flow Efficiency has been under emphasized.  It is the fundamental concept behind avoiding wasted time on a large project.   In the new paradigm of balancing the interests of the individual while maintaining the interests of the group of stakeholders working together, Resource efficiency is the analog of the interests of the individual and Flow efficiency is the analog of the interests of the group as a whole. 

The galactic complexity of time management in a construction project became one of the primary thrusts of Lean Construction.