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Sub-Contractor Audit Checklist

A sub-contractor audit tests a trade's work against the contract, the project ITP, and the relevant Australian Standards. The checklist below is the framework QBFS uses on builds across Australia. It's not a script — a real audit goes deeper than the checklist on whatever the audit reveals — but it sets the structure most audits follow.

Before the audit

Pre-audit preparation:

  • Audit scope. Which trade or work package, which stage of work, which standards apply, what areas of the site.
  • Document review. The sub-contract, the project ITP for this trade, the relevant Australian Standards, prior audit reports, prior NCRs, the trade's own QA records, any RFI responses affecting the work.
  • Programme check. Where is this trade against their programme? Have they mobilised, started, completed?
  • Site coordination. Who from the head contractor is attending? Who from the trade? When and where?
  • PPE and induction. Standard site PPE, current site induction, any specific trade-area requirements.

A well-prepared audit goes faster on site and produces a sharper report.

On site, the structural checks

  • Materials on site match the specification. Brand, grade, size, source. Where alternative products have been used, is the substitution documented and approved?
  • Install sequence matches the manufacturer's instructions. Especially relevant for products with strict install protocols (waterproofing membranes, fire-rated systems, structural fixings).
  • Hold-points have been inspected and signed off. Each hold-point in the ITP up to this stage should have a corresponding sign-off in the trade's QA record.
  • Witness-points have been attended where required.
  • Sample testing has been done where the ITP calls for it. Concrete cylinder results, soil compaction tests, water tightness tests, captured and filed.
  • The work is in spec for measurable elements. Tolerances on dimensions, levels, finishes. Tape and level used.
  • The work is in spec for visual elements. Quality of finish, alignment, integration with adjacent trades.

On site, the documentation checks

  • Mill certificates and product certificates for all materials requiring traceability.
  • Manufacturer install certificates where the install requires a certified installer.
  • Conformance evidence captured at each hold-point per the ITP.
  • Trade's own quality records complete, current, filed.
  • Prior NCRs addressed, with evidence of close-out.
  • As-built documentation matches the installed work.

On site, the workmanship checks

  • Setting out and alignment. Lines, levels, plumb where the standard requires.
  • Joints and connections. Closed properly, sealed properly, structurally appropriate.
  • Edges and terminations. Treated to the standard's requirements (especially relevant for waterproofing, cladding, fire-rated systems).
  • Penetrations and interfaces. Where one trade's work passes through another's, the interface meets both trades' specifications.
  • Surface finishes. Free from defects that compromise function or aesthetic per the contract.

Trade-specific elements (varies by audit scope)

Different trades have different audit priorities. A few examples:

Waterproofing:

  • Membrane brand and grade against specification
  • Substrate preparation
  • Coverage thickness and continuity
  • Termination details (penetrations, junctions, drainage points)
  • Manufacturer install certificate
  • Water tightness testing record

Structural concrete:

  • Reinforcement detailing matches drawings
  • Cover and spacing
  • Concrete grade and slump per pour record
  • Cylinder testing record
  • Curing protocol
  • Post-tensioning records if applicable

Fire-rated separation:

  • System matches the FRL specified
  • Penetrations sealed to FRL
  • Doors, frames, hardware to specification
  • Manufacturer install records for fire-rated systems
  • As-built fire compartmentation diagram

Acoustic separation:

  • System matches the Rw / DnT specified
  • Penetrations sealed for acoustic performance
  • No flanking paths around or through the separation
  • Test results if commissioning testing is required

The audit report

The audit produces a written report:

  • Audit scope and methodology
  • Trade and sub-contractor identification
  • Conformance findings
  • Non-conformance findings with photographs, references, recommended close-out
  • Pattern observations
  • Assessment of the trade's own QA records
  • Overall conclusion

NCRs are issued separately for each non-conformance item, with the report referencing the NCR numbers for the audit trail.

After the audit

  • Issue the report to the head contractor.
  • Issue NCRs to the trade for each non-conformance.
  • Schedule close-out verification. Each NCR gets a follow-up inspection to confirm remediation.
  • Update the QA file.

For repeat trades on the project, audit findings feed the risk register and inform the next audit's scope.

Where QBFS conducts sub-contractor audits

QBFS conducts sub-contractor audits on residential, multi-residential, and commercial projects across Australia.

Call Paul on 0407 146 737.

Start With a Call

Tell Paul the project. The next step gets sorted on the call.

Best way to start is a phone call. Tell Paul the project, the issue, where you sit in the build cycle. The next step gets sorted on the call: site visit, desktop review, or a referral if QBFS isn't the right fit.
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