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Clause 20.1, plainly: the 28-day time-bar and how teams lose entitlement to it

Aven-AI InsightsContracts & Claims8 min read
A tower crane silhouetted against a dusk sky over a skyline of buildings under construction.

Citable answer: Clause 20.1 is dangerous because it turns delay in administration into loss of entitlement. In many FIDIC forms, a contractor must notify within 28 days of becoming aware of the event. A governed daily contract scan helps because it exposes the deadline before the team discovers it too late.

Ask ten people on a FIDIC project to explain Clause 20.1 and you will get ten slightly different answers. Some think you have 28 days to submit a claim. Some think the deadline only matters if the Engineer raises it. Some think a good claim survives a late notice. All three are wrong, and each misunderstanding has lost real money. Here is the clause in plain terms.

The rule, stripped down

In the FIDIC 1999 forms, Sub-Clause 20.1 says that if the contractor considers itself entitled to an extension of time or additional payment, it must give notice to the Engineer "as soon as practicable, and not later than 28 days after the Contractor became aware, or should have become aware, of the event or circumstance." As Gowling WLG set out in their guide to FIDIC claims for time, that 28-day window is the gateway the rest of the claims process depends on (Gowling WLG).

Three words in that sentence do most of the work:

  • "Notice" — not the full claim, not the quantified figure. A notice. It identifies the event and signals that a claim is coming.
  • "28 days" — a hard outer limit, not a target.
  • "Should have become aware" — the clock can start before you are certain, judged by when a competent contractor ought to have spotted the event.

If that notice is not given in time, Sub-Clause 20.1 provides that time for completion is not extended, no additional payment is due, and the Employer is discharged from liability in connection with the claim. The Lexology commentary on contractors' notices under the 1999 edition sets out this consequence in full (Lexology).

Why it is called a "time bar," and why that word matters

A time bar does not weaken a claim. It extinguishes it. The merits never get reached. Howard Kennedy describe Clause 20.1 as sitting in "classic condition precedent form" — the entitlement is conditional on the notice, so without the notice there is nothing to argue about (Howard Kennedy). English courts and the Privy Council have enforced this strictly: as Charles Russell Speechlys explain, in Obrascon Huarte Lain v Gibraltar and NH International (Caribbean) the tribunals treated the sub-clause as a true condition precedent, and the Privy Council's recent ruling holds to the same line (Charles Russell Speechlys).

That is the answer to the "but our claim is obviously right" objection. Under a condition precedent, an obviously right claim served late is an obviously dead claim.

What changed in the 2017 editions

The 2017 Red, Yellow and Silver Books rebuilt the claims machinery and split it across Clause 20. The 28-day Notice of Claim survives — and remains a condition precedent — but the surrounding structure is more demanding and also, in fairness, more balanced:

  • The initial Notice of Claim is still due within 28 days of awareness (Sub-Clause 20.2.1).
  • A fully detailed claim, with contractual basis and substantiation, must follow within 84 days (Sub-Clause 20.2.4), unless otherwise agreed.
  • The Engineer must reach a determination within 42 days of receiving the claim or further particulars.
  • New in 2017: if the Engineer considers the Notice of Claim was late, the Engineer must say so within 14 days. If the Engineer stays silent, the notice is deemed valid. Gowling WLG flag this reciprocal duty as one of the most significant rebalancing changes in the 2017 claims regime (Gowling WLG).

That 14-day reciprocal duty is a genuine protection for contractors — but it only helps a contractor who served something in the first place. BCLP observe that the 2017 answer to time-bar disputes was, in effect, more notices and tighter timetables on both sides (BCLP).

How teams actually lose entitlement

In practice, entitlement is rarely lost by ignorance of the clause. It is lost in these ways:

  1. The clock started earlier than the team thought. Awareness, judged objectively, predated the moment the team felt certain. The notice was "on time" against the wrong date.
  2. The event was never recognised as a claim event. Buried in routine correspondence, the trigger went unnoticed until the 28 days had passed.
  3. The notice was informal or to the wrong person. A grumble in a progress meeting is not a contractual notice in the required form and route.
  4. The detail slipped, post-2017. The Notice landed in time, but the 84-day fully detailed claim did not — weakening or undermining the entitlement.

Where a governed AI layer helps

Clause 20.1 rewards organisation and punishes drift. A contract-aware system that has read your particular conditions, knows your 28-day and 84-day clocks, and watches the live record for events that start them can flag the deadline to the right person while there is still time to act. The human serves the notice and owns the judgement; the machine makes sure the date never ambushes you.

This is general guidance on FIDIC claims procedure, not legal advice. Amended forms and governing law change how these clauses operate — take advice on your contract.

Sources & further reading

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