Lean Onboarding Series – Cycle Times

No Championship Team Runs a Play for the First Time in the Big Game

No football team wins a championship by running a play for the very first time during the big game itself. Championship teams win with plays they have practiced over and over, precisely because that repetition is what reduces their mistakes and sharpens their execution under pressure. The same logic applies directly to construction task durations, and understanding why requires a genuine production principle worth knowing directly: Kingman’s formula.

The Real Pain: The “Ideal” Duration Is Never the Real Duration

The real pain is a common planning mistake: taking an idealized crew working at one hundred percent productivity and using that number as the actual committed task duration. No real crew operates that way, especially not on a task they are encountering for the first time. Planning around that idealized number, rather than a genuinely realistic one, sets a schedule up to miss its own targets from the very start.

The Failure Pattern: Committing to the Optimistic Number Instead of the Realistic One

The failure pattern is promising a task duration based on the best-case scenario, rather than honestly accounting for the real variation and below-ideal productivity every crew genuinely experiences, particularly early in an unfamiliar task. That optimistic commitment feels aggressive and efficient on paper. In practice, it consistently produces schedules that cannot actually be met.

This Isn’t Pessimism, It’s Kingman’s Formula

None of this is about assuming the worst or doubting a crew’s genuine capability. Kingman’s formula is a real, established production principle that accounts mathematically for two specific factors: the real variation a crew will experience, and their actual productivity level, which is rarely, if ever, a full one hundred percent, especially on a task they have not yet fully mastered.

From Four Days to Five and a Half

Here is a concrete example worth understanding directly. A task might look like it should take four days for an ideal four-person crew working at full, one hundred percent productivity. Once real, expected variation gets factored in, honestly, that same task is more realistically closer to four and a half or four and three-quarters days. Once the crew’s actual productivity level gets factored in as well, particularly if this is a newer or less familiar task for them, the honest duration climbs further still, closer to five and a quarter or five and a half days.

That final number, not the original idealized four days, is the genuinely realistic duration worth planning around.

Why It Matters: What You Promise Shapes What You Can Actually Deliver

This matters because of what happens when durations get packaged into a schedule or a Takt wagon. Committing to the optimistic four and a half day estimate, rather than the honest five to five and a half day reality, sets the entire plan up to fail before work even begins, not because the crew performed poorly, but because the original plan was never actually realistic in the first place.

A few signs help reveal when a planned duration has quietly skipped past Kingman’s formula, and they are worth checking honestly:

• A task duration was calculated using an idealized crew size and one hundred percent productivity, without any real accounting for variation.
• The crew assigned to a task is encountering it for the first time, with no adjustment made for their inevitably lower initial productivity.
• Repeated missed durations on similar tasks keep getting treated as isolated incidents rather than a pattern worth genuinely correcting in future planning.

Teach the Framework: Start Realistic, Then Improve

The practical guidance worth adopting directly is this: commit to the honest, realistic duration from the very beginning, then work to gain buffer and genuinely improve from that starting point, rather than beginning with an optimistic number and hoping the crew simply hits it. This mirrors exactly how a football team actually improves: practicing the same play repeatedly, using each repetition specifically to reduce variation and increase productivity, gradually earning back real time through genuine practice rather than assuming that time exists from the very first attempt.

A few practical steps help apply this directly to setting and improving task durations:

• Calculate an honest starting duration that accounts for both real variation and a crew’s actual, not idealized, productivity level.
• Treat repeated practice of a similar task type as the genuine mechanism for improvement, not a hopeful assumption baked into the first attempt.
• Track actual performance against the realistic starting duration, using any real gains as genuine buffer rather than assuming that buffer upfront.

Turning This Into Daily Practice

When planning task durations, honestly account for both real, expected variation and a crew’s actual productivity level, especially for new or unfamiliar work. Treat repeated practice of the same task type as the real mechanism for earning back time and building genuine buffer, the same way a football team improves specific plays through repetition, rather than assuming that improvement will simply happen on its own from the first attempt.

Connecting It Back to Building People, Not Just Projects

None of this happens without leaders willing to plan honestly around real variation and real productivity, rather than defaulting to an idealized, best-case number that sets a crew up to fail before they even begin. Building that realistic planning discipline directly into how durations get set is exactly what allows genuine improvement to happen over time, rather than repeating the same missed commitments project after project.

If your project needs superintendent coaching, project support, or leadership development, Elevate Construction can help your field teams build the kind of realistic scheduling discipline that actually holds up under real-world conditions.

The Challenge

So here is the challenge worth carrying into your next scheduling conversation: check whether a planned task duration accounts honestly for real variation and actual crew productivity, or whether it quietly assumes an idealized best case that was never realistic to begin with. As Jason put it plainly, a real task duration is “not just the task, it’s also the variation they experience and the productivity level of the crew.” On we go.

FAQ

What is Kingman’s formula, translated for construction?

It is a production principle stating that a task’s true duration depends not just on the ideal time an ideal crew would need, but also on the real variation that crew will experience and their actual, often below-ideal, productivity level. This produces a more honest, realistic estimate than simply assuming best-case performance.

Why does a task’s “ideal” duration rarely match its real duration?

An idealized duration assumes a crew working at full, one hundred percent productivity with no variation, which rarely reflects real working conditions, especially for a task a crew has not yet fully mastered. Accounting honestly for both variation and actual productivity typically extends the realistic duration well beyond the idealized estimate.

Why does the football team analogy matter for understanding task durations?

Just as a championship team wins by executing plays they have practiced repeatedly, rather than running a brand-new play for the first time in a critical moment, a construction crew improves task performance specifically through repeated practice of similar tasks. Real improvement in cycle time comes from that repetition, not from optimistic assumptions made before the work has even begun.

What happens when a schedule commits to an optimistic duration instead of a realistic one?

The plan tends to miss its own targets, not because the crew performed poorly, but because the original estimate never genuinely accounted for real variation and actual productivity levels. This creates a pattern of missed commitments that gets mistakenly treated as a performance problem rather than a planning one.

How can a team actually improve its task durations over time?

By starting with an honest, realistic duration and then genuinely practicing and repeating similar tasks, a crew can gradually reduce variation and increase productivity, earning back real time as genuine buffer. This approach produces lasting improvement, unlike assuming that buffer exists from the very first attempt at a task.