NEC4 compensation event timescales calculator
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Z clauses often shorten the 8 weeks. NEC subcontracts (ECS) use different periods. Enter the periods in your contract, including extensions agreed before expiry (62.5). Calendar weeks apply — Construction Act exclusions do not.
Calendar-week periods (all editable)
Enter a step date to start the timeline.
The notification bar has an exception where the PM should have notified the event (61.3). Deemed acceptance requires a valid failure notice and continued silence. For 64.4, this concerns the Contractor's quotation, not an unsubmitted quotation.
Not legal or tax advice — check your contract. Your contract terms and the facts of your job can change the answer.
How this works
Contractor notification: default 8 weeks from awareness (61.3), with the exception where the PM should have notified. PM reply: 1 week or an agreed longer period (61.4). A failure notice starts a further 2-week period for conditional acceptance as a CE and an instruction to quote.
Quotation: 3 weeks after instruction; PM reply: 2 weeks after submission (62.3). Revised quotation: 3 weeks after instruction to revise (62.4). Quotation/reply periods may be extended by agreement before expiry (62.5). A valid quotation failure notice starts a further 2 weeks before conditional acceptance (62.6).
PM assessment: within the quotation period from when the need becomes apparent (64.3), default 3 weeks. Following a valid failure notice, a further 2 weeks without response can result in acceptance of the Contractor’s quotation (64.4). Enter the applicable quotation period here if changed.
FAQs
Do bank holidays extend NEC periods?
No. These are calendar weeks, not Construction Act days.
Does every missed reply mean acceptance?
No. The relevant valid failure notice and continued silence are required. Check the contract and notification requirements.
Can I use this for ECS?
Enter your own periods. NEC subcontracts and Z clauses can change these ECC defaults.
Can periods be extended?
Quotation and reply periods may be extended by agreement before they expire (62.5). Update the entered periods.
Civvio works this out automatically from your contract and site records.
Upload the contract and keep your diary, and Civvio flags the dates, notices and money at risk on every job — for you to review before anything is sent.
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