FIDIC.uz · Calculator
Interim Payment Certificate (IPC)
Amount due this period = cumulative value of work and materials − retention − advance repayment − previously certified. Clause 14 (2017).
What this tool does
The amount due for the period = cumulative value of work and materials − retention − advance payment recovery − amounts previously certified. The Clause 14 logic is cumulative: each certificate recomputes the whole picture from project start rather than the current month alone, so corrections to earlier periods flow into the current IPC automatically.
Where the inputs come from
- Cumulative value — the total from project start, not the month’s output; otherwise the result is out by a wide margin.
- Retention percentage and its limit — Contract Data entries; once the limit is reached no further retention accrues.
- Advance payment recovery — per the contract formula, usually a percentage of the period amount above a threshold.
- Previously certified — the sum of all earlier IPCs, not just the last one.
How to read the result
The figure produced is what to apply for, not what will necessarily be certified. The Engineer may decline items unsupported by measurement and documentation, so a gap between application and certificate is normal rather than a sign of conflict. What is worth contesting is not the reduction as such but the specific items struck out, asking for written reasons on each.
What this tool does not account for
- Does not apply price-fluctuation or change-in-law adjustments where the contract provides for them.
- Does not compute tax or currency conversion where payment is made in more than one currency.
- Does not check the minimum interim certificate amount below which no certificate is issued.
- Does not reflect Employer deductions on other grounds — cross-claims or delay damages, for instance.
Questions
Why is the certified amount lower than the amount applied for?
Most often because of quantities not confirmed by joint measurement, materials on site without delivery and title documentation, or items the Engineer treats as not yet executed. The first step is not an argument but a request for a written line-by-line breakdown: in most cases the issue closes on documents rather than debate.
Are materials on site included in an interim payment?
Generally yes, where the contract provides for it and its conditions are met: the materials are delivered to site, conform to specification, are properly stored and insured, and title passes to the Employer. The precise conditions sit in the Contract Data and Particular Conditions, and are worth reading before the first application rather than after a rejection.