Evidence That Wins Adjudications: A Subcontractor Checklist

You’ve done the work. The invoice is overdue. The head contractor isn’t returning calls. Now you’re thinking about adjudication—and wondering if you’ve got enough to win.

The truth is, adjudication under Australia’s Security of Payment legislation isn’t a lottery. It’s a process that favours the subcontractor with the better paperwork. If you can show the adjudicator what you’ve done, when you did it, and what you’re owed, you’re in a strong position. The problem is most tradies and small builders don’t realise what counts as “strong” until it’s too late.

This checklist walks you through the evidence that actually matters in an adjudication—and what you should be gathering now, before a dispute happens.

1. Your Contract and Variation Orders

Start here. Every Security of Payment Act across Australia—whether it’s the NSW SOP Act 1999, QLD Building Industry Fairness (Disputes) Act 2017, or VIC SOP Act 2002—hinges on what you were contracted to do and what you were paid to do it.

You need:

• Signed contract (or email chain showing agreement if nothing was signed)
• Scope of works, specifications, or drawings you relied on
• Any variation orders, change requests, or written amendments to the original scope
• Email approval from the head contractor or site manager authorising extra work
• The agreed payment schedule (lump sum, progress claims, hourly rate—whatever was agreed)

If your contract is shaky or missing, don’t panic. Courts and adjudicators accept evidence of agreed work through correspondence, text messages, and site manager instructions. But a clean, signed contract saves you headaches later.

2. Your Payment Claims and Correspondence Trail

This is gold. Every email, message, or formal claim you send creates a time-stamped record of what you’ve done and what you’re chasing.

Keep and organise:

1. Copies of every payment claim you’ve issued (with dates)
2. Invoices with line-item descriptions of work performed
3. Emails chasing payment (these show the head contractor knew about the debt)
4. Any acknowledgement from the head contractor that they received your claim
5. Responses where they dispute part of the work or say “payment coming next week”
6. Proof of your previous payments being made on time (if they were)

Under the NSW SOP Act 1999 and similar legislation, the respondent (head contractor) has specific timeframes to respond to your payment claim—usually 10 business days. If they don’t respond, they owe you what you claimed. If they do respond with a payment schedule saying they’ll pay less, or nothing, that’s evidence they’ve rejected your claim. Write that date down.

Text messages and WhatsApp chains count. Keep them.

3. Site Records and Work Evidence

Adjudicators want to see that you actually did what you say you did. Your word alone isn’t enough. Evidence of the work is.

Gather:

• Daily site diaries or timesheets – signed by you or a witness, showing what work you did each day
• Photos and video – dated images of your work in progress and completed (phone photos are fine; they’re automatically time-stamped)
• Site inspection reports or handover documents – signed by the head contractor or their rep accepting the work
• Material delivery dockets – showing what you supplied, when, and where it went
• Payroll records or subcontractor timesheets – proof of labour you’ve paid for
• Quotes from suppliers – for materials you claim you’ve provided

If you can show the head contractor signed off on your work or a stage payment, that’s powerful. It’s harder for them to later claim the work wasn’t done.

4. Communication About Disputes or Delays in Payment

Record every conversation about payment. Not just the final “you owe me” message, but the whole story.

Document:

• When you first raised the issue and how (email, message, in person)
• What the head contractor said about why payment was delayed (cash flow, waiting for another payment, disputing quality)
• Any promises to pay and when they said it would happen
• Follow-up requests and responses (or non-responses)
• Any indication they were disputing only part of the work, or the timing, not the whole claim

This narrative matters. An adjudicator reads it and gets a clear picture of good faith on your side and avoidance on theirs.

Before You File: Get Organised

Before you file a payment claim, spend a day pulling together everything above. Create a folder with:

• Contract and variations
• Payment claim(s) and invoices
• Email trail (in chronological order)
• Site diaries and photos
• Any handover or sign-off documents
• Proof of your costs (wages, materials)

You don’t need to attach everything to your initial claim. But have it ready. If the head contractor disputes your claim in their response, your evidence is already organised and ready to go to adjudication.

The faster you can pull it together, the faster you can move through the process. Under most state SOP Acts, an adjudication decision happens within 10–15 business days of the adjudicator being appointed. That’s tight. Being prepared now means you don’t panic later.

The Bottom Line

Adjudication isn’t about who has the loudest voice—it’s about who has the clearest evidence. Contracts, claims, photos, diaries, and emails all tell a story. The subcontractor who tells that story clearly wins the adjudicator’s attention and trust.

Start gathering this evidence now. Don’t wait until money is owed. The tradies and small builders who stay on top of paperwork are the ones who sleep easier when cash flow gets tight.