Where a programme shows slack, either within the sequence or between planned completion and the contract date, both parties would like the benefit of it. Contracts are usually silent and the argument is usually unresolved until it matters, which makes it a recurring feature of extension of time claim preparation.
The two kinds of float behave differently and are argued about differently, so the first useful step is to say which kind is in issue.
Activity float
Slack on an activity that is not on the governing chain: it can slip, within limits, without affecting completion.
Where an employer risk event consumes that slack without delaying completion, no extension is due, because completion was not delayed.
Cost may still have been incurred, which is why that situation belongs in a money claim rather than a time one.
Terminal float
The gap between the contractor’s planned completion and the contract completion date.
Contractors regard it as their own contingency, priced into the tender. Employers frequently regard it as belonging to the project.
The contract rarely says, which is why the argument is about construction and commercial logic rather than about a clause.
The contractor’s argument
That the float was planned and priced, and that the obligation is to complete by the contract date rather than by the planned date.
That an employer event consuming the float has deprived the contractor of its own contingency, which has value.
And that the alternative encourages contractors to conceal float, which serves nobody.
The employer’s argument
That an extension is for delay to completion, and while float remains completion is not delayed.
That the contractor cannot claim relief for a date it was not obliged to meet.
Which is a strong argument on the words of most forms, and is why the employer’s position frequently prevails on the time question.
What the contract sometimes says
Some amendments address it expressly, allocating float to the project or preserving it for the contractor.
Some require the programme to show completion on the contract date, which removes terminal float by eliminating it.
Reading the particulars and the amendments settles the question where they deal with it, and takes minutes.
Float that was never real
Programmes sometimes show float that reflects optimistic durations rather than genuine contingency, which weakens any argument built on it.
Equally, programmes constrained to the contract date sometimes conceal float inside durations, which is a different problem.
A programme built from resources and output is the only answer to either, and it is worth the time at the start.
Float in the middle of the project
Float changes as work progresses, so the position at the date of the event is what matters rather than the position at the start.
That means the programme updates are the evidence, and their absence is frequently what makes the argument unresolvable.
Keeping dated updates costs almost nothing and settles this question whichever way it falls.
Money where time is refused
Where an event consumed float without delaying completion, the contractor may still have incurred cost, and that route remains open.
Disruption and additional preliminaries do not depend on the completion date moving.
Framing the claim that way from the start avoids spending the entitlement argument on a time claim that the float defeats.
Acceleration and float
Where a contractor absorbs an event by working faster rather than later, the float position may be what made that possible.
Whether the cost of doing so is recoverable depends on whether it was instructed and on what the contract says about mitigation.
It is worth raising at the time rather than presenting as a claim afterwards, because an instruction changes the position entirely.
How assessors handle it
Generally by asking whether completion was delayed, which is the question the contract asks.
Where it was not, the time claim fails and the cost claim may not, which is a sensible place for the argument to end.
A submission that acknowledges the float position rather than ignoring it is easier to assess and tends to do better on the parts that survive.
What to do at tender
Decide whether to show the float and understand the consequence either way.
Check whether the amendments allocate it, because that changes what the programme should show.
A programme that hides contingency inside durations is harder to manage and harder to claim from, which is a cost that arrives later.
What to do during the works
Keep the programme updated and dated, so the float position at any point can be established.
Notify events as they arise whether or not float appears to absorb them, because the float may be gone by the time the effect is felt.
That second point is the one most often missed, and it is where entitlement is quietly lost.
Why the argument keeps arriving
Because float has value and the contract usually does not allocate it, which leaves a gap that both parties fill with their own commercial logic.
Because the programme that would settle it is frequently not maintained, so the position at the date of the event cannot be established either way.
And because the consequence is large: the same event either carries relief or does not, depending entirely on whether the slack was there when it struck.
Where it fits
Float governs whether an event produced delay at all, so it comes before both entitlement and quantum.
Where it defeats the time claim, the money route is loss and expense and it should be prepared instead rather than afterwards.
The programme updates that settle the question belong with commercial management during the works.
Running late with nobody agreeing why?
Extension of time claim preparation sets out the events relied on, their effect on the programme and the contractual route to relief, in a form that can be assessed rather than argued over.