If you've ever done extra work on a job and then struggled to get paid for it, you're not alone. Variation orders — sometimes called change orders or extras — are one of the biggest sources of lost income for NZ tradies. Research from MBIE's Building Performance unit consistently shows that disputed variations are a leading cause of construction payment disputes in New Zealand.
The good news: a clear, documented variation process protects you legally, keeps clients happy, and puts money in your pocket. This guide covers exactly how to set one up.
What Is a Variation Order?
A variation (or variation order) is any change to the agreed scope of work in your original contract or quote. This includes:
- Additional work the client requests mid-job (extra room, upgraded fittings, design changes)
- Unforeseen conditions you encounter (rotten framing behind cladding, asbestos, poor ground conditions)
- Design changes initiated by an architect, engineer, or the client's builder
- Compliance-driven changes where council or WorkSafe requires something not in the original spec
The key principle: if it wasn't in your original quote, it's a variation. Full stop.
Why Tradies Lose Money on Variations
The most common trap is doing the extra work first and raising the invoice later. At that point, the client has already got what they wanted — and now they're questioning your price. Without a signed variation, you have very limited legal standing.
Under the Construction Contracts Act 2002, a variation that isn't documented and agreed to in writing can be genuinely difficult to recover. If a dispute ends up at adjudication, a verbal "yeah, just do it" from the client rarely holds up.
The second trap is under-pricing variations. When a client asks for a quick change mid-job, it's tempting to give them a rough ballpark. But variations often carry hidden costs: remobilising labour, reordering materials at short notice, breaking and redoing finished work, and extending your overall programme. Use our Job Cost Calculator to price variations properly before you agree to anything.
The Right Way to Handle a Variation
1. Stop work (or flag it) before proceeding
As soon as you identify a potential variation, stop and communicate. A simple message — "Hey Dave, this is outside our original quote. Happy to do it but I'll need to send you a variation first." — sets the right expectation and protects you professionally.
If stopping work would cause damage or safety issues (e.g., you've opened a wall and found unexpected structural issues), document everything with photos and timestamps immediately, then raise the variation as soon as practicable.
2. Prepare a written variation order
A variation order doesn't need to be fancy — even a clear email or PDF with these elements is sufficient:
- Job reference (your quote or contract number)
- Date
- Description of the variation — be specific about what's changed and why
- How it differs from the original scope
- Additional materials (itemised with quantities and unit costs)
- Additional labour (hours × rate, including travel if mobilising)
- GST-exclusive subtotal, then GST, then total including GST
- Impact on programme (extra days or weeks if applicable)
- Acceptance field — a space for the client to sign and date
You can build a clean variation document quickly using our Quote Builder Wizard, which handles the GST calculations automatically.
3. Get sign-off before you start
This is non-negotiable. A signed variation is your insurance policy. In practice, many clients will approve via email or text — under the Construction Contracts Act, written communication (including email) counts as a valid contract variation provided the terms are clear and accepted.
If a client won't sign off before you start, that's a red flag. You may choose to proceed for relationship reasons, but do so with your eyes open: you're taking on financial risk.
4. Price variations at your current rates
Don't price variations at the same rate as your original quote, especially if:
- Material costs have risen since you quoted (and in 2026, many have — steel, copper, and timber all saw price increases in Q1 2026 according to Statistics NZ PPI data)
- The variation requires short-notice orders or express delivery
- You're mobilising a team back to site for a small scope of work
A fair approach is to price variations using your standard charge-out rate plus a materials markup (typically 15–25% for NZ tradies to cover procurement, storage and warranty risk). Use our Markup & Margin Calculator to make sure you're hitting your target gross margin.
What to Include in Your Original Contract
The best time to make variations easy is before the job starts. A well-written contract should include:
- A clear variation clause stating that all variations must be requested in writing and approved in writing before work proceeds
- Your standard labour rate for variation work (hourly rate applies if not separately quoted)
- Materials markup percentage (e.g., "materials at cost plus 20%")
- Programme impact — how variation work affects the overall timeline and whether it triggers any delay costs
- Deposit and payment terms for variation invoices (e.g., payable within 14 days of completion)
MBIE's standard construction contract guidance recommends all residential building work over $30,000 includes a written contract — and variations are a core part of that.
Handling Disputes Over Variations
If a client refuses to pay a variation invoice, you have options under NZ law:
1. Payment claim under the Construction Contracts Act 2002 If the variation is related to construction work, you can serve a formal payment claim. If the client doesn't respond with a valid payment schedule within the statutory timeframe (5 working days for residential, 20 working days for commercial), the full amount becomes payable by law.
2. Adjudication Fast, relatively cheap dispute resolution through AMINZ or Building Disputes Tribunal. Many adjudicators are experienced in variation disputes — having your written variation order, approval evidence, and contemporaneous notes (photos, messages, site diary) will make or break your case.
3. Debt collection / small claims For smaller amounts, the Disputes Tribunal handles claims up to $30,000 without needing a lawyer.
Practical Templates
Many NZ tradies use Fastcrew to manage variations digitally — clients can approve variation requests from their phone, with a timestamped audit trail that holds up in disputes. It integrates with Xero and MYOB, so your variation invoices flow straight through to your accounts.
For a paper-based or editable template, download our free NZ tradie contract and variation templates at tradietools.nz/templates/
Quick Reference: Variation Pricing Checklist
Before you submit any variation order, run through this:
- [ ] Have I itemised all additional materials (with current market prices)?
- [ ] Have I included labour hours at my current charge-out rate?
- [ ] Have I accounted for travel and remobilisation?
- [ ] Have I noted any programme (timeline) impact?
- [ ] Is GST correctly applied?
- [ ] Have I included an acceptance/sign-off field?
- [ ] Am I getting sign-off before starting the work?
The Bottom Line
Variations are a normal part of construction — but they're only profitable if you manage them properly. Tradies who document variations diligently, price them correctly, and get written approval before proceeding protect their margins and have far fewer payment disputes.
It takes a little discipline up front, but it's the difference between a job that makes money and one that quietly bleeds it.
NZ Tradie Tools provides free calculators, templates and guides for New Zealand tradies. Visit tradietools.nz.