Skip to content
Contact us
  • There are no suggestions because the search field is empty.

Increasing Remaining Duration

Increasing Remaining Duration occurs when an activity’s remaining duration goes up between updates, or doesn’t go down as much as the elapsed time would suggest. It means the activity is taking longer than planned, even if its original duration and logic haven’t changed.

Ex: An activity has a 20-day original duration and starts on schedule. After 10 working days, it should have about 10 days remaining. The update shows 15 days remaining, so the activity has slipped 5 days and will finish 5 days later than previously forecast.

How increasing remaining duration can affect the schedule:

  • Schedule delay: A longer remaining duration pushes the activity’s finish date later and uses up float on its path. On the critical path, where there’s no float to absorb it, each added day extends project completion by a day.
  • Cost increases: Time-related costs such as general conditions, supervision, site overhead, and equipment rental keep running for the added duration. Delayed downstream trades may pass their costs along, and recovery efforts like overtime or added crews cost extra.
  • Resource inefficiencies: Growing remaining durations often point to productivity problems, such as undermanned crews, labor or material shortages, rework, access or sequencing conflicts, or an overly optimistic estimate. Resources planned for the next phase may sit idle waiting for the delayed activity.
  • A remaining duration that stays the same or increases from one update to the next is a stronger warning sign. It suggests work has stalled or the scope is larger than estimated.

Best Practices:

  • Compare remaining durations for the same activities across consecutive updates, focusing on critical and near-critical work.
  • Check that remaining duration matches reported percent complete. For example, an activity at 75% complete with most of its duration still remaining needs a closer look.
  • Document the reason when remaining duration increases, such as added scope, a change order, or a field condition. This separates legitimate re-planning from unexplained slippage.
  • Watch for the opposite pattern too. Remaining durations reduced without a clear reason can hide real delays by compressing work on paper.