"Schedule Update Analysis: Retained Logic versus Progress Override"

by Devdas K. Tamboli, CCE PSP, Julie K. Owen, CCC PSP, and Ahmad Ali Ahmed Alkuwari

Abstract:

Construction industry standard schedule specifications most often require retained logic as the schedule calculation setting when updating the schedule. Use of this calculation setting can sometimes prove problematic when out of sequence progress occurs and result in inaccurate information and artificially impacted float values.

The progress override calculation setting can also be problematic because using this method ignores predecessor schedule logic for activities in progress. Owners prefer retained logic and contractors prefer progress override. These differing viewpoints can impact the validity of the project schedule.

This paper will evaluate the pros and cons of using each calculation method, typical scheduling specification language, and give industry examples. The impact of using each method will be evaluated for proper schedule updates and delay claim analysis. Finally, recommendations will be offered for use of progress override when correcting out of sequence schedule logic is not possible.