Why 40 percent of change events slip through the cracks: the diary was written. Nobody read it against the contract in time. The event is on a line. The notice is not. Clause 61.3 does the rest.
Manual diary review typically captures about 60% of legitimate change. On a typical £50 million job with a 3% variation allowance (£1.5 million), the missing 40% is £600,000. That is not a soft number. It is several million pounds of extra turnover you would need, at a thin margin, to earn the same cash back.
Why experienced people miss it
A junior reviewer sees concrete pour postponed, weather, pour moved to day 48 and files weather. A senior QS sees the twenty-third weather line in eight weeks and asks whether the exceptionally adverse weather threshold has been crossed. The notice period often closes before that second reading happens.
A review of 200 to 400 entries, against a dozen clauses, with several clocks running, is not a Sunday-night job. After a few hundred lines, pattern recognition drops. Each entry looks isolated. Four weekend shifts look like operational choices. Together they can be acceleration after a late design change.
What £600,000 looks like on one job
Thirty-one weather lines over twelve weeks, each normal British weather, adding up to 22% of available time against a 20% threshold. A cascade of client instructions priced as variations, with the disruption (method statements, sequence, premium materials, extra supervision) never claimed. Plant breakdowns from one hire firm treated as your risk. Weekend working logged as programme maintenance when the cause sits in an earlier diary line.
Find it at final account and the client will say the individual events were routine. Fresh evidence in the first four weeks is a different conversation from a reconstruction six months later.
The clocks
NEC4: usually eight weeks to notify a compensation event. JCT: loss and expense in a reasonable time. FIDIC: often 28 days from awareness. A monthly diary review can put you four or five weeks into an eight-week window before anyone starts the notice.
Write the event that day in the site diary. Read it that week, not that quarter.
What to do next
Write the hours and the activity in the site diary that shift. Then let Rosie read those lines against the contract so a notice goes while the clock is still running.
Key Takeaways
- A slipped CE is usually a diary nobody read that week, not a missing fact.
- Write the event that day in the site diary.
- Rosie reads those entries against NEC4 so a near-miss is raised while the clock is still running.
Related blogs you may like
Unbilled Variations: How Much Revenue Is Your Site Losing?
Unbilled variations are revenue leakage. The change happened on site. If it is not on the diary that day, it will not be on the application.
Variation Order Management: How NEC4 Clause 60 Benefits from Gather's New Variance Categorisation Feature
Compensation event vs variation. NEC4 clause 60 lists the events. A diary that says "extra work" does not tell a QS which one it is.
NEC Contract Management and Contract Management in Construction
NEC contract management is the diary, the allocation and the notice, written that day. A register filled in later is not administration.
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