Most turnaround overruns are baked in long before the unit comes down. Here are the planning failures that cause them, and the scheduling discipline that prevents each one.
A turnaround is the most schedule-sensitive thing a process plant ever does. Every extra day of downtime carries a six-figure cost, and yet a striking number of shutdowns finish late. The frustrating part: the slip is usually decided weeks before the unit ever comes down.
Here are the failures we see most often, and the discipline that stops each one.
1. Scope that never froze
The single biggest cause of overrun is scope growth. Worklists keep absorbing "while we're in there" items right up to execution, and none of them are sequenced or resourced.
The fix: a hard scope freeze tied to a milestone, with a formal, costed change process after it. If a late item can't show its schedule and resource impact, it waits for the next window.
2. Optimistic, unlinked schedules
A schedule with missing logic links isn't a plan — it's a wish list with dates. When activities float free, the critical path is fiction and float is invisible.
The fix: full CPM logic, realistic durations built from norms and history, and resource loading so the plan reflects the crews you actually have.
3. No single source of progress truth
When progress is self-reported by discipline, every meeting starts with an argument about percent-complete. Decisions get made on the loudest opinion, not the data.
The fix: one integrated schedule, updated daily, with progress measured against defined rules. Everyone reads from the same curve.
The morning a turnaround gets a single, trusted progress picture is the morning decision-making changes on the floor.
4. Recovery starts too late
By the time a slip is obvious to everyone, the cheap recovery options are gone. Without daily look-aheads and what-if analysis, the team is always reacting.
The fix: rolling 3-week look-aheads, daily critical-path review, and pre-built recovery scenarios so the response is a decision, not a scramble.
The common thread
None of these fixes require new technology. They require planning discipline applied consistently — before and during the event. That discipline is exactly what a dedicated planning desk exists to provide, whether it sits in your office or delivers remotely to your P6 environment.
If your last turnaround slipped, the schedule almost certainly told you it would. The question is whether anyone was watching the right number, every day.