Chapter One: Introduction to Schedules - Construction Schedules - Fifth Edition
Michael T. Callahan is President of CCL Construction Consultants, Inc. He maintains an active international consulting practice in the measurement and responsibility of delay, along with the quantification of additional performance costs and other construction and design-related matters. The author of Termination of Design Contracts, he also prepares a monthly newsletter summarizing current design and construction case decisions for Construction Law Digest. Mr. Callahan has lectured throughout the United States, Europe, the Middle East and Far East on design and construction-related topics. He is a member of the Kansas, New Jersey, and Missouri bars by examination. He is also a frequent arbitrator, negotiator, mediator, and a regional advisor to the American Arbitration Association.
H. Murray Hohns, PE, Fellow ASCE, was a Construction Consultant, Mediator and Arbitrator in private practice. His specialty was construction delay, those responsible, and its consequences. He founded Wagner-Hohns-Inglis-Inc. and built it into one of the country’s 250 largest Consulting Engineers. The author of several books on dispute resolution, he worked on projects in all 50 states and overseas, and managed major construction projects for their owners. Mr. Hohns also wrote a monthly expert commentary for a compilation of reported construction cases for over seven years. He was former President of the Project Management Institute, the National Academy of Forensic Engineers, and a member of the Board of Directors for the American Arbitration Association.
Scheduling of a construction project or any other project is nothing new nor is it terribly complicated if one understands the activities required to bring the project to completion. People have been planning and carrying out both simple and complex projects for thousands of years. Our times may include electronic and environmental features not common just 50 years ago, but the concept of scheduling the labor, tools, material and equipment necessary to do any and all projects in some sort of necessary sequence has been with us since history began.
The Old Testament relates the construction of Solomon's Temple to use thirty thousand forced laborers that were rotated at ten thousand per month in and out of Lebanon; another seventy thousand laborers and eighty thousand stone cutters were put to work in the hill country of Israel, and were overseen by three thousand three hundred supervisors. All those people were evidently necessary to build a rather ornate building that was only 30 feet wide, 90 feet long and 45 feet high, and to build it so that the ring of a hammer, ax, or any iron tool was never heard at the temple site while it was being built. Obviously, someone did some planning and scheduling during the seven years that it took to form its construction.
While we know that a scheduling method called a bar or Gantt chart has been used as a planning tool for the last 85 years or so, little is known about how people went about planning large construction or other projects prior to the bar chart. Moreover, it was not until the development of network diagramming techniques which can show activity or specific job task relationships, that the scheduling of construction and all other projects began to receive serious attention. Soon after this method was developed, the law changed at the Federal level and the schedule began to receive its most attention when someone was trying to prove their entitlement to more time and money on a project which was completed later than the contract required.