What does the agent check on each line of the certificate?
Every line of an IPC has a source somewhere else in the project. The agent reads that source rather than the figure typed on the claim, and flags where the two disagree.
| Line | What the agent reads | What it flags for the QS |
|---|---|---|
| Measured work | Site quantities, inspections and package progress to date | Claimed quantities with no inspection or measurement behind them |
| Variations | Instructions and authorised change decisions | Variations claimed but not instructed, or instructed but not yet valued |
| Retention | The rate and any limit set in the subcontract | A rate or cumulative amount that does not match the subcontract |
| Advance recovery | The recovery terms and the payment history | Recovery running ahead of, or behind, the agreed schedule |
| Previous certificates | The full certificate history for the subcontract | A total that differs from what was certified, or a period paid twice |
| Contra-charges | Notices and back-charge records | A deduction proposed without the notice the subcontract requires |
What does a checked claim look like?
The figures below are illustrative and follow the worked example in what goes into a subcontractor payment certificate? The subcontractor has claimed more than the records support, and the agent's draft shows where the difference comes from.
| Line | Subcontractor's claim | Agent's draft | Reason for the difference |
|---|---|---|---|
| Work measured to date | 1,250,000 | 1,200,000 | 50,000 of claimed work has no inspection record yet |
| Variations to date | 110,000 | 80,000 | 30,000 relates to work not yet instructed |
| Gross valuation | 1,360,000 | 1,280,000 | The two lines above |
| Less retention at 5% | − 68,000 | − 64,000 | Retention follows the lower gross valuation |
| Less advance recovery | − 50,000 | − 50,000 | Agrees with the subcontract schedule |
| Less previously certified | − 900,000 | − 900,000 | Agrees with the certificate history |
| Net amount due | 342,000 | 266,000 | A difference of 76,000, each part sourced |
The agent does not decide that the 50,000 is not due. It shows that the evidence is missing, so the quantity surveyor can ask for the inspection, measure it again or certify it on their own judgement. A planned IPC calculator will let anyone run the arithmetic on their own figures.
What does the agent prepare, and what does the quantity surveyor decide?
The split follows the difference between gathering evidence and exercising judgement.
- The agent prepares the gross valuation from measured work and approved variations, the deductions from the subcontract terms and the certificate history, a line-by-line comparison with the claim, and the list of missing evidence.
- The quantity surveyor decides whether a measurement is right, whether a disputed item is certified this period, whether a contra-charge is justified, and what to say to the subcontractor.
- An authorised person commits the certificate. Only then does it update committed cost, reach the finance ledger and move the cash expectation.
Why does the agent stage the certificate instead of issuing it?
Because a payment certificate is a commercial decision with a contractual consequence, and the agent is designed never to make one. Staging means the draft exists as a proposed change in the ERP, visible to the people who must review it, with the evidence attached. Nothing reaches cost, finance or the subcontractor until an authorised person commits it.
The same rule holds for the release of what was held back, which is covered in how the agent tracks retention release. How the agent's limits are enforced is on the security and AI governance page.
Common questions
Can the agent certify a subcontractor payment?
No. The agent prepares a draft certificate and stages it as a change, with the evidence behind each line and every difference from the claim. A quantity surveyor reviews it and an authorised person commits it. The agent cannot approve, issue or pay a certificate.
What does the agent need to prepare an IPC?
It needs the records the ERP already holds for the subcontract: measured work and inspections, instructed and approved variations, the retention and advance recovery terms, notices and back-charges, and the history of earlier certificates. Where a record is missing, the agent says so instead of filling the gap.
Does the agent handle retention and advance payment recovery?
Yes. It reads the retention rate, any limit and the recovery schedule from the subcontract, applies them to the gross valuation, and checks the cumulative amounts against earlier certificates. It flags any figure on the claim that does not match those terms.
What happens when the subcontractor disagrees with the draft?
Each line of the draft points to its source, so the conversation moves from where a number came from to whether a measurement is right. The quantity surveyor decides what to certify, and the audit trail keeps what was claimed, what was proposed and what was approved.
Crolle is opening early access to a small group of contractors and partners. To see it on your own projects, write to info@crolle.ai.