What documents should be collected first?

Start with approved budget, BOQ, contract value, actual spend records, purchase orders, invoices, progress reports, delay notes, and material consumption records.

Can a leakage audit run with missing documents?

It can begin, but missing evidence should be shown clearly. Unsupported amounts, causes, and recovery actions should not be invented.

Are BOQ values leakage?

No. BOQ value, planned spend, standard contract value, cumulative work done, and advance recovery are baseline budget signals unless separate evidence shows leakage.

What documents support delay cost?

Delay cost review usually needs schedule records, daily progress reports, procurement evidence, idle resource logs, and cost records tied to the affected activity.

Documents Needed for a Construction Cost Leakage Audit

Documents That Make Leakage Review Possible

A construction cost leakage audit needs records that show baseline budget, actual cost, procurement movement, progress status, material use, delay evidence, and commercial correspondence. Start with the approved budget, BOQ, contract value, actual spend records, purchase orders, invoices, material logs, progress reports, delay notes, site instructions, and penalty or rework records. If a document is missing, the audit should record the gap rather than guess a cause or amount.

Practical checklist

Approved budget, BOQ, contract value, planned spend, and revised budget records.
Actual spend records, invoices, payment certificates, purchase orders, and supplier bills.
Material issue sheets, consumption logs, stock reports, wastage notes, and reconciliation files.
Schedules, lookahead plans, progress reports, daily reports, delay notes, and site instructions.
Penalty, rework, idle resource, delayed procurement, excess consumption, and claim correspondence.
ESG records when cost, energy, water, fuel, waste, diesel, electricity, or carbon evidence is part of the review.

Example table

Document	Why it matters	Likely output
Approved budget and BOQ	Defines baseline values.	BASELINE_BUDGET classification.
Actual spend and invoices	Shows incurred cost evidence.	Actual value used for overrun calculation when Budget is available.
Purchase order register	Shows procurement timing and approval status.	Delayed PO impact review if cost or delay evidence supports it.
Daily progress reports	Connects field status to schedule and resource use.	Delay, idle resource, or missing-evidence finding.

Internal links

For the service workflow, see construction cost leakage audit. For the calculation method, read BOQ vs Actual cost overrun. To see a sample output, open the synthetic executive demo.