Float

The time an activity can slip without moving the end of the plan, or without delaying the activity that follows it.

Float is found, not granted. Once the milestones are pulled backward to today and every row of The activity table carries a duration and its links, the arithmetic says how much room each row has. Total float is how far an activity can slip before the end moves; free float is how far it can slip before its successor is delayed. Free float can never exceed total float — an activity may have weeks of one and none of the other, because what it feeds is waiting. Float belongs to an activity's place in the logic, not to the activity itself. Time a team sets aside on purpose is a buffer; time the network allows is float.

It is load-bearing because it tells a body where its freedom actually is. The rows with none are Critical Path; the rest are where work can be reordered and hands can be lent without cost. And when a finish-by inherited from a Milestone cannot be met by the logic, float goes negative: the plan is late by that many days before a day of work is done. That is lateness made visible early, and the honest response is to re-pull, shrink a handoff, add hands or remove a constraint — written in The Record with its why, rather than quietly re-baselined.

Float consumed is a leading measure. A plan runs with zero float to a milestone's plan date, and the season between that date and the marker is contingency, spent knowingly and said aloud. Spent without saying so, it is drift.

Also called: slack Stands on: The activity table · Pull planning · Predecessor / Successor Opens onto: Critical Path · Milestone · Honesty about time · Measure everything, manage to the milestones In play: table · beyond Sources: Float (wiki term page, drafts, unreviewed; the fullest treatment) · The LIØNSBERG Operating System (book, draft v0) §4–5 · The DNA of Heaven, Part VII — lionsberg.wiki page name: Float Open: The scheduling literature says slack for the same quantity; here float names the number and buffer names time placed on purpose.