What notice periods apply under NEC contracts?

NEC runs on the compensation event, its single mechanism for changes, delays and most other money and time events, and the unamended NEC4 ECC hangs default periods off it. The contractor notifies a compensation event within 8 weeks of becoming aware that the event has happened, and for the events the contractor should notify, that 8 weeks is written as a condition of entitlement, the classic time bar; events arising from the Project Manager or Supervisor giving an instruction, issuing a certificate or changing an earlier decision sit outside it, because those are the Project Manager's to notify. The Project Manager then replies to a notification within 1 week, a quotation follows within 3 weeks of being instructed, and the Project Manager replies to the quotation within 2 weeks, with deemed acceptance rules picking up silence at several steps. Early warnings sit alongside: each party notifies as soon as it could be aware of a matter that could raise cost or time, and a matter that was not early warned can have its compensation assessed as if it had been. All of these are the unamended defaults, and Z clauses, NEC's schedules of amendments, shorten them often enough that the printed numbers are only the starting point.

Picture a civils subcontractor on an unamended NEC4 job hitting unexpected ground conditions in March. It notifies the compensation event in week 2, well inside the 8, the Project Manager replies inside a week, and a quotation is instructed. The quotation goes in within its 3 weeks and the reply comes 2 weeks later: about 7 weeks from ground to agreed change, while the same event under a claims led contract would still be a file waiting for the final account. Run the same story with the notification in week 10 and the entitlement is gone entirely. The lesson is that NEC pays the fastest administrator, not the best arguer.