Resources / Insight
Time-bar Watchtower
What clause-cited notices actually do for you.
Most missed time-bars in UK construction are not contested. They are not the result of a legal argument about whether the clause applies. They are simply unnoticed — the window opened, the window closed, and nobody was watching. The contract does not forgive that. The clock does not care.
The problem
Missed time-bars are not contested — they are unnoticed.
A time-bar in a UK construction contract is a contractual deadline — a window within which a notice must be issued, or the right to that notice is lost. The window can be as short as five days. The trigger is often an event on site that is not, in itself, remarkable: a client variation instruction, a programme impact, a late delivery of OFCI equipment. The event happens. The QS is on a different job that morning. The window opens. The window closes.
The cost is not theoretical. A single missed Pay Less Notice under a JCT contract can mean paying a sum applied for by the sub-contractor in full — regardless of the merits of the application. On a large data-centre package, that can be a seven-figure number. The failure mode is not incompetence. It is the QS being on a different project that morning, or the event not reaching the commercial team until the window has already passed.
The fix is not more QSs. The fix is a system that watches every clock, drafts inside the window, and names the human owner who must sign before the window closes. The system cannot sign. Only Coughlan can sign. But Coughlan needs to know the window is open.
Two examples from the Cranebank contract set
The clause, the window, the consequence.
Example 1 · NEC4 Option C
Early Warning — NEC4 clause 15
Under NEC4 ECC clause 15, the contractor has an obligation to give an early warning notice as soon as they become aware of a matter that could increase the total of the Prices, delay Completion, or impair performance of the works. There is no fixed window — but the obligation arises at awareness, not at impact. Failure to give a timely early warning can reduce the compensation the contractor is entitled to receive.
Cranebank · Hall 2 · UPS delivery delay flagged at site meeting · Early Warning NEC4/EW-014 drafted and queued for Coughlan within 4 hours of the meeting record being closed.
Example 2 · JCT D&B 2024
Pay Less Notice — JCT D&B 2024 clause 4.9.5
Under JCT D&B 2024, a Pay Less Notice must be issued not later than five days before the final date for payment. It must state the sum the payer considers due and the basis of that calculation. Miss the window by one day and the sum applied for becomes the notified sum — payable in full regardless of any dispute about the valuation.
Cranebank · Apex Mechanical Package · Interim Application 11 · Pay Less Notice window: 5 days · Watchtower amber at day 2 · draft queued for Coughlan on day 2 · signed and issued on day 3 · two days inside the window.
The four stages · how the Watchtower works
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1
Clause located in the contract on intake
When the contract is uploaded, the engine extracts every time-bar clause — notice windows, response deadlines, Pay Less Notice obligations, Early Warning triggers. They are indexed against the contract form and version. They do not need to be re-entered for each event.
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2
Trigger event detected
An event on site — a variation instruction, a payment application, a programme impact — is logged in the system. The engine matches it against the time-bar register. The relevant clause, window, and responsible person are identified automatically.
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3
Time-bar started
The clock starts at the trigger event. Amber alert at 50% of the window consumed. Red alert at 80%. The alert names the responsible person — Coughlan, in the case of most commercial notices on Cranebank — and includes the clause, the window end date, and the current draft.
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4
Draft notice queued for Coughlan to sign
The clause-cited draft notice sits in Coughlan's review queue before the amber threshold. He reads it. If the clause is right, the valuation basis is right, and the wording is right, he signs. The notice issues. The window closes, with the notice inside it. If Coughlan disagrees with the draft, he edits it — and the audit trail records both the draft and his amendment. The system never issues. Coughlan issues.