Builders and renovators · Variations

How should a builder communicate a price variation to a homeowner?

By BREME · Updated 22 October 2026

Who this is for: Residential builders and renovators in Australia who need to tell a homeowner that the price is changing mid-job, and want to keep the relationship intact while following their state's variation rules.

Why variations go wrong

Most homeowners don't object to a variation itself. They object to finding out late, finding out on an invoice, or feeling the number was decided without them.

The QBCC says that failing to properly record and approve variations before they are carried out is one of the most common causes of serious building disputes. The fix is mostly about order: conversation first, paperwork second, work third, payment last.

A variation is also a moment where the homeowner decides whether they trust you for the rest of the job. A clear, early, plain-English message does more for that trust than any discount.

What the rules say, state by state

In Queensland, the QBCC says a variation must be in writing and the owner must agree to it in writing before you start the variation work. The written variation must be easy to read, describe the change, state the date of the request, give your reasonable estimate of any delay, and state the change to the contract price (or how it will be worked out). If the price changes, it must say when an increase is to be paid or a decrease credited. You can't require payment for a variation before the variation work starts.

Queensland also sets a timing rule for the copy: give the owner a written copy before the domestic building part of the variation work starts, or within 5 business days of both parties agreeing, whichever happens first. The exception is urgent work where producing a written copy first isn't reasonably practicable. The QBCC also reminds contractors to update home warranty cover when a contract is varied.

In Victoria, Consumer Affairs Victoria says builders are legally required to use a Variation Notice to change a major domestic building contract, unless you reasonably believe the change won't need a permit change, won't cause delay and won't add more than 2% to the original contract price. It still recommends a Variation Notice for every change. You and your client must agree in writing before the work begins, and the contract must be updated with the new price and completion date.

Victoria also says the client shouldn't have to pay for variations ordered to fix things you should have identified before starting, such as excavation costs you could have predicted from the foundation data.

Other states have their own rules and standard contracts. Check your state regulator's guidance and your contract's variation clause, and talk to an adviser if you're unsure.

The order to do it in

1. Call or meet the homeowner the day you know a variation is likely. Explain what you found, why it matters and the options, before you put a number in writing.
2. Send the written variation the same day or the next, using your contract's variation form (in Queensland, a Form 4 or Form 5 depending on the contract type; in Victoria, the Variation Notice in Part D of the new homes contract template).
3. Include the description, the reason, the price change with a short breakdown, any delay in days, and when payment falls due.
4. Wait for their signed agreement before starting the varied work, unless it is genuinely urgent and your state's rules allow it.
5. Confirm in writing once signed, with the updated contract price and completion date.
6. Show the variation as its own line on the next progress claim so there are no surprises.

How to word it so it lands well

Lead with the reason, not the number. Homeowners accept a cost far more easily when they understand what changed: a hidden problem behind a wall, a council requirement, or their own change of mind.

Give a choice where one exists. Two or three options with different prices make the homeowner a decision-maker rather than someone receiving a bill.

Be specific about time. 'This adds about 4 working days' is better than 'a slight delay'.

Keep the written variation factual and the covering message warm. The form does the legal work; the message does the relationship work.

If the homeowner pushes back, slow down. Offer to walk them through it on site, and don't start the varied work until you both agree in writing.

Hi [first name], it's [your name] from [business]. While [doing the work] today we found [what you found]. It means [what needs to change]. I'd like to talk you through the options before anything goes ahead. Are you free for a quick call or a site visit at [time]? Nothing extra will start until you've agreed in writing.

Subject: Variation [number] for [address]: [short description]

Hi [first name],

Thanks for talking this through [today/yesterday]. As promised, the variation is attached for you to review.

What changed: [plain description of what you found or what they asked for].
Why it's needed: [reason, such as structural, council or safety requirement, or your requested change].
Options: [Option A and its price change] or [Option B and its price change].
Price change: [amount and breakdown].
Time: this adds about [number] working days, so the estimated completion date moves to [date].
Payment: [when the increase will be claimed, such as with progress claim number X].

We won't start this work until you've signed and returned the variation. If anything isn't clear, call me on [number] or I can meet you on site.

[Name]
[Business], [licence number]

Hi [first name], thanks for signing variation [number]. Your updated contract price is [amount] and the estimated completion date is [date]. We'll start this work on [date], and it will appear as its own line on progress claim [number]. Any questions, just reply.