Figures checked 1 October 2026. Consumer Affairs Victoria’s Owner builders guidance says a builder, contractor or tradesperson must give an owner-builder domestic building insurance (DBI) for work more than $16,000, while the owner-builder must also take out DBI to protect a future buyer and obtain their own insurance for their own work; a written contract is required for domestic building work more than $10,000, even if the owner signed the building permit. If the owner sells within six years and six months after completing the building work, they must provide a defects inspection report no more than six months old from a registered building practitioner for all work, regardless of value; the same guidance says DBI covers costs up to $300,000 to fix structural defects for six years and non-structural defects for two years, and a buyer can use it only if the owner-builder dies, becomes insolvent or disappears.
What makes someone an owner-builder in Victoria?
Consumer Affairs Victoria says a person is an owner-builder if they intend to:
- use their own skills to build, extend or renovate their home;
- manage subcontractors who will do the work; or
- work on their own property as a registered builder.
The role carries many of the responsibilities of a registered builder, along with the associated financial risks. Most laws applying to registered builders also apply to owner-builders. Their rights and responsibilities are governed by the Domestic Building Contracts Act 1995 and the Building Act 1993.
An owner-builder is responsible for doing all or part of the work personally, except work that must be carried out by licensed tradespeople. Consumer Affairs Victoria recommends always using licensed plumbers, along with licensed electricians and asbestos removalists where asbestos removal is required.
What does the owner-builder have to arrange?
The owner-builder remains responsible for the project even when specialist tradespeople carry out parts of it.
| Area | Owner-builder responsibility |
|---|---|
| Own work | Do all or part of the work personally, except work requiring licensed tradespeople. |
| Tradespeople | Contract the work and check that tradespeople are registered and licensed where required. |
| Insurance | Arrange insurance and retain the relevant insurance documentation. |
| Worker safety | Take responsibility for the occupational health and safety of workers. |
| Planning | Obtain relevant planning permits from the local council and be named as the owner-builder on permits. |
| Building approvals | Engage a building surveyor to obtain building permits, including an occupancy permit or certificate of final inspection on completion. |
| Inspections | Arrange legally required inspections at the relevant stages of the work. |
| Compliance | Ensure the work meets building regulations, standards and other laws. |
An owner-builder may also engage a building consultant for independent advice during construction. The consultant can check the quality of both the owner-builder’s work and the work of other people engaged on the project.
When is a written plumbing contract required?
Consumer Affairs Victoria records that, from 1 August 2017, the threshold for a major domestic building contract increased from $5,000 to $10,000.
| Trigger | Contract requirement |
|---|---|
| Domestic building work more than $10,000 | The owner and builder, contractor or tradesperson must enter into a written contract, even if the owner signed the building permit as owner-builder. |
| Before signing a major domestic building contract | The builder must give the owner-builder a copy of the Domestic Building Consumer Guide. |
Consumer Affairs Victoria recommends using registered builders for work over $10,000, or to reblock, restump, demolish or remove a home regardless of the work’s value.
Be careful if a plumber or other tradesperson asks you to sign the building permit while they will do the work. Consumer Affairs Victoria warns that the tradesperson may be unregistered and/or trying to avoid legal responsibilities, which can cost more than expected. Contact Consumer Affairs Victoria or a lawyer for advice before agreeing to act as owner-builder in those circumstances.
What does the $16,000 DBI threshold trigger?
The $16,000 threshold connects several separate requirements. It is not a substitute for checking the consent, contracting and insurance rules together.
Consumer Affairs Victoria sets out the following requirements:
| Rule | When it applies | What must happen |
|---|---|---|
| Certificate of consent | Before carrying out domestic building works over $16,000 | The owner-builder must obtain a certificate of consent from the Building and Plumbing Commission (BPC). This is a consent requirement, not the DBI itself. |
| Builder’s or tradesperson’s DBI | Work more than $16,000 | A builder, contractor or tradesperson must give the owner-builder DBI for the work. It protects the owner-builder if that provider dies, disappears or becomes insolvent. |
| Protection for the property buyer | Owner-builder work over $16,000 | The owner-builder must take out DBI to protect a future property buyer. |
| Cover for the owner-builder’s own work | For work over $16,000 | The owner-builder must obtain their own domestic building insurance to cover their own work. |
The builder’s or tradesperson’s obligation does not remove the owner-builder’s responsibility to insure their own work. Consumer Affairs Victoria also says warranties still apply.
Why does my own work need separate cover?
If a registered building practitioner carried out work for the owner-builder under a major domestic building contract, Consumer Affairs Victoria says that work should be covered by the practitioner’s DBI. That does not cover the work the owner-builder personally carried out.
The guidance therefore treats these as separate needs:
- the practitioner provides DBI protection for work the practitioner carries out;
- the owner-builder takes out DBI to protect a future buyer; and
- the owner-builder obtains their own domestic building insurance for their own work.
To obtain DBI, ask the insurance provider which documents it requires. Consumer Affairs Victoria says the owner-builder will need the defects report and the domestic building insurance certificates supplied by builders or tradespeople for work on the project.
What must I provide if I sell early?
An early sale creates a separate owner-builder reporting requirement. Consumer Affairs Victoria requires the owner-builder to provide a defects inspection report with the following features:
| Requirement | Rule |
|---|---|
| Sale window | The property must be sold within six years and six months after completion of the building work. |
| Report age | The defects inspection report must be no more than six months old. |
| Author | It must come from a registered building practitioner. |
| Scope | It must cover all work regardless of value, including extensions, renovations, garages and verandas. |
This reporting requirement and DBI have different time limits. The defects-report requirement is tied to a sale within six years and six months after completion, while DBI no longer covers the property after six years.
What does DBI cover for a buyer?
DBI, formerly called builders warranty insurance, is intended to protect a buyer in specific circumstances. It is not a response to every building defect.
| Question | Consumer Affairs Victoria rule |
|---|---|
| When does cover become effective? | Once the contract of sale is signed. |
| When can the buyer use it? | Only if the owner-builder has died, become insolvent or disappeared. |
| How much is covered? | Costs up to $300,000 to fix covered defects. |
| How long are structural defects covered? | Six years. |
| How long are non-structural defects covered? | Two years. |
| What happens after six years? | The property is no longer covered by DBI. |
| Are listed defects covered? | DBI does not cover defects or incomplete work identified in the defects inspection report. |
Warranties still apply despite DBI. The owner-builder should therefore not assume that every issue recorded in an early-sale defects report can be claimed under DBI.
Did the Domestic Building Contracts Amendment Bill 2025 change these thresholds?
Consumer Affairs Victoria records that the Domestic Building Contracts Amendment Bill 2025 passed the Victorian Parliament on 11 September 2025. Its current owner-builder guidance continues to set out the $10,000 contract threshold and the $16,000 consent and insurance thresholds; the cited material does not state that passage of the Bill replaced either amount. Check the regulator page before signing a contract or starting work.
What should I check before work starts?
- Confirm who is acting as owner-builder and who will be named on the permits. Do not sign a building permit merely because a plumber or other tradesperson asks you to.
- For domestic building work more than $10,000, put the agreement with the builder, contractor or tradesperson in writing and obtain the Domestic Building Consumer Guide before signing a major contract.
- For work over $16,000, obtain the BPC certificate of consent before starting, arrange buyer-protection DBI and separate cover for your own work, and check the builder’s or tradesperson’s DBI documentation.
- Obtain relevant planning permits from the local council and engage a building surveyor for building permits and completion approvals.
- Check that tradespeople are registered and licensed where required, and use licensed plumbers.
- Arrange required inspections and make sure the work will comply with building regulations, standards and other laws.
Partner links. Using them costs you nothing extra and may earn us a commission.