The short answer
In Victoria, NSW and Queensland the rule is the same in spirit: extra work should be agreed in writing, with the cost and any extra time, before it starts. Do not agree to extras on the spot or by text alone, and do not pay for a variation before the work on it has started.
General information read in full from government pages on 12 November 2026, not legal advice. Exceptions exist, such as urgent work.
What each state says
From the regulators:
- VictoriaYou and the builder must agree in writing to variations using a Variation Notice before the work starts. A notice is not required if the builder reasonably believes the change will not need a permit change, cause delay or add more than 2% to the original price. The contract must record the details, the new total price and the new completion date.
- New South WalesVariations must be in writing, attached to the contract and signed by both you and the builder. If there is likely danger to someone or damage to property, the written variation may be done after the work.
- QueenslandThe contractor must present the variation to you in writing and you must agree to it in writing. You must get a written copy before the variation work starts, or within 5 business days of agreeing, whichever is earlier. The contractor cannot require payment for a variation before the variation work has started.
Protect yourself
- ask for every change as a priced written variation
- check the new total price and finish date
- do not pay for extras until the signed variation is in place
- keep copies with your contract
Common questions
Can a builder do extra work without a written variation?
The regulators say variations should be in writing before the work starts, with narrow exceptions such as urgent work.
Is there a size limit for a Victorian variation?
A Variation Notice is not required if the change will not need a permit change, cause delay or add more than 2% to the original price, and the builder reasonably believes that.
Sources
- Consumer Affairs Victoria: changing a major domestic building contract, checked 12 November 2026
- NSW Government: contracts for residential building work, checked 12 November 2026
- QBCC: contract changes and variations, checked 12 November 2026