Terminal float in NEC4 is the gap between planned Completion on the programme and the Completion Date in the contract. It isn't a defined term; it is what planners call that gap. In effect it stays with the Contractor, because compensation event delay is measured from planned Completion, and the Completion Date moves by the same amount.
The same logic applies under NEC3, where the rule is at 63.3 instead of NEC4's 63.5. This page looks at the end of the programme only. For float within the sequence, see who owns float in NEC, and for the overall framework, the NEC programme guide.
Why the assessment rule protects it
Take a fictional leisure centre, with weeks as illustrative dates. The Accepted Programme shows planned Completion in week 60. The Completion Date is week 64. Terminal float is four weeks.
A Client instruction delays the critical path by two weeks. Planned Completion moves to week 62. The delay is two weeks, so the Completion Date moves to week 66. Terminal float is still four weeks.
If the rule measured delay against the Completion Date instead, that event would have produced no extension: planned Completion in week 62 is still before week 64. The Contractor's margin would have been spent on the Client's event. That is the outcome NEC's method avoids. The compensation event delay guide has a table covering other scenarios.
What can use it up
| Cause | Effect on terminal float |
|---|---|
| Implemented compensation event | Normally no effect. Planned Completion and the Completion Date move together |
| Contractor's own delay | Reduces it, once planned Completion moves later |
| Contractor's own recovery or early finish | Increases it |
| A risk event the Contractor carries, such as ordinary weather | Reduces it |
| An accepted acceleration quotation | Set by the quotation: earlier Completion Date and a revised programme |
This is the reason terminal float is valuable to a Contractor: it is the time buffer for its own risks before delay damages under Option X7 come into play.
Can a Project Manager object to it?
Not as such. A programme showing planned Completion ahead of the Completion Date isn't one of the four reasons for not accepting in 31.3. The Project Manager could reasonably test whether the plan is realistic, because a shortened programme showing six weeks of terminal float might not reflect how the work will actually be done. That is a different objection from saying the float shouldn't be there.
A Client that wants the earlier date has two routes. It can set a more demanding Completion Date before the contract starts, or use clause 36 to pursue an agreed acceleration.
Finishing early isn't always straightforward
Terminal float doesn't guarantee that the Client will take the works on the earlier date. Under clause 35.1, the Contract Data can say the Client isn't willing to take over before the Completion Date. Without that entry, take over comes no later than two weeks after Completion. If you plan an early finish, check that entry. Under Option A, payment for the last activities is due when they are completed, so a real early finish can help cash flow, but your preliminaries and security costs may continue until the Client takes over.
How to show it
- Show planned Completion and the Completion Date as separate milestones, and show the gap between them with a labelled bar.
- Don't place planned Completion on the Completion Date, with a fat activity hiding the gap. Hidden float reads as a fully critical programme, which undermines the programme's credibility.
- Don't confuse it with a time risk allowance. Those are built into operations; terminal float comes after the last of them.
- Check the same point on your Key Dates. A similar gap can exist between a planned date for meeting a Condition and the Key Date, and delay is assessed in the same way.
A point on honesty
A revised programme should honestly show the current position. If terminal float has gone because of the Contractor's own delays, show that. Trying to protect the buffer on paper invites a non-acceptance for being unrealistic, and it weakens the baseline for the next compensation event.
Related guides
- The NEC Programme: A Complete Guide
- Time Risk Allowance in NEC
- Who Owns Float in NEC?
- Completion Date and Planned Completion
- Submitting the First Programme
- How Often to Revise the Programme
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