IPCs are usually issued monthly. The contractor submits an application for payment based on measured quantities against the bill of quantities (BOQ), approved variations and materials on site; the engineer or consultant checks it and certifies the amount due.
Certificates are cumulative: each one shows the gross value to date, deducts what was certified before, then applies retention, advance payment recovery and any other deductions agreed in the contract. In the UAE, VAT is then charged on the taxable value of the certificate and a tax invoice is issued.
How Civova handles it
Civova builds each certificate cumulatively (this period, previous and to date) against the project's BOQ, applies the contract's retention percentage and advance recovery, and turns the certified amount into a VAT tax invoice that posts to the ledger.