Permits, registration and contracts for a Victorian bathroom renovation
Permits, builder registration, contracts and warranty for a Victorian bathroom renovation in 2026, written for a Narre Warren homeowner doing a first one.
Four things trigger a building permit in Victoria, and a like for like bathroom inside the existing walls usually hits none of them. The paperwork you will certainly meet is a contract above ten thousand dollars, two trade certificates, and a warranty scheme that changed on 1 July 2026.
This page is the single place on this site where the Victorian rules are set out in full. Everything else here links back to it.
Two points of language first, because they matter when you are checking someone. In Victoria builders are registered and plumbers and electricians are licensed, so a builder holds a registration rather than a licence. And the regulator changed name and form: the Building and Plumbing Commission is now the body that registers builders and licenses plumbers. The Victorian Building Authority no longer exists, so anything still pointing you at it is out of date.
When is a building permit required?
All building work needs a building permit unless Schedule 3 of the Building Regulations 2018 exempts it. A bathroom renovation that replaces what was there, inside the existing external walls, floor and ceiling, usually falls inside those exemptions. The exemptions are conditional, though, so only a building surveyor can confirm it for a specific job. A permit is triggered when the work involves any of the following.
- Work affecting the structural soundness of the building.
- A change in floor area or in height.
- Underpinning.
- Removing or altering a loadbearing element.
Point four is the one that catches Narre Warren homeowners. The standard 1970s and 1980s three bedroom plan through this suburb puts the toilet in its own small room off the hallway, next to the bathroom. Combining those two rooms into one is the most requested change here, and whether the dividing wall is loadbearing has to be established before the job is priced, not discovered during demolition. If it is loadbearing, the job needs a permit and an engineered beam.
Waterproofing a wet area is not itself a permit trigger. Replacing a shower, a bath, a vanity, tiles and a membrane in the same positions generally is not either. Pushing the bathroom into the adjoining bedroom or the linen cupboard changes the layout of the building and needs checking.
In the City of Casey the building permit is issued by a private building surveyor engaged by the owner, not by the council. The council still handles things around the job rather than the job itself. If a skip or a materials load has to sit on the road or the nature strip, Casey asset protection and skip bin permits apply. Those fees change, so treat any figure you are quoted for them as current at the time of writing and confirm it when you apply.
Who is allowed to do the work?
| Trade | Requirement |
|---|---|
| Builder or renovator | Registered building practitioner for domestic building work worth more than ten thousand dollars, as Domestic Builder (Unlimited) or the limited class Domestic Builder (Limited to bathroom, kitchen and laundry renovation) |
| Plumber | Licensed plumber, compliance certificate required for plumbing work valued over seven hundred and fifty dollars and for below ground sanitary drains and gas work at any value |
| Electrician | Licensed Electrical Worker employed by a Registered Electrical Contractor, Certificate of Electrical Safety required |
| Asbestos removal | Licensed asbestos removalist |
| Waterproofer | Waterproofing applied to AS 3740, current edition 2021, as called up by the National Construction Code |
The limited registration class is worth understanding, because it is the right class for most bathroom work. Domestic Builder (Limited to bathroom, kitchen and laundry renovation) covers wet area work that does not extend beyond the existing external walls, floor or ceiling. A renovator holding that class can lawfully run your bathroom job. If the job pushes out past those boundaries, the unlimited class is needed.
The ten thousand dollar figure counts labour, materials and GST together, so it is the whole price of the job and not the labour component.
The certificates you should end up holding
The plumbing compliance certificate is the one most homeowners never see. The plumber has five days to issue it and five days to lodge it, and it carries six years of insurance from the date it was issued. Ask for a copy rather than assuming it will arrive.
The electrical side produces a Certificate of Electrical Safety, issued for the new exhaust fan, lights, power and any heat lamp. Both documents belong to you and both are worth keeping with the house papers, because a purchaser’s conveyancer will eventually ask about the wet area work.
What has to be in the contract?
A written major domestic building contract is required at the same threshold as registration: domestic building work worth more than ten thousand dollars. In practice every full bathroom renovation in Narre Warren is a contract job.
Deposit limits are set by law and they are low on purpose.
| Contract price | Maximum deposit |
|---|---|
| Under twenty thousand dollars | 10 per cent |
| Twenty thousand dollars or more | 5 per cent |
A request for a larger deposit, or for a cash payment up front before a contract is signed, is the clearest early warning sign there is. The contract should also carry the scope in detail, the start and completion dates, the progress payment stages, and how variations are agreed and priced in writing before the extra work is done.
The warranty that applies from 1 July 2026
From 1 July 2026 the First Resort Home Warranty Scheme replaced Domestic Building Insurance. It applies to work valued at more than twenty thousand dollars on a home up to three storeys. It covers defective work for up to six years after completion, and the maximum assistance is four hundred thousand dollars per home.
Domestic Building Insurance and its sixteen thousand dollar threshold still exist, but only for contracts signed before 1 July 2026. If your contract is signed now, the new scheme is the one that applies to you.
A job under the threshold is not covered by the scheme. That is worth saying plainly, because a smaller job priced just under twenty thousand dollars sits outside it. Separately from any scheme, the statutory warranty period for domestic building work in Victoria is 10 years. That 10 years is the limitation period for bringing a building action, and no renovator can convert it into a 10 year or lifetime waterproofing warranty of their own. Anyone offering one is describing something they have invented.
What standard does the waterproofing have to meet?
Wet area waterproofing is done to AS 3740, current edition 2021, as called up by the National Construction Code. Victoria adopted NCC 2025 on 1 May 2026.
Shower walls are waterproofed to 1800 mm above the floor substrate. That height is a National Construction Code requirement through the ABCB Housing Provisions rather than something set by AS 3740 itself, which is why a quote that names only the standard has not told you the whole requirement. The membrane is applied in coats, each coat cures before the next, and the finished system cures before tiling starts.
Asbestos in a pre 1990 house
Asbestos cement sheet was the standard wet area lining from the 1940s to the mid 1980s. That covers the great bulk of the older brick veneer through Narre Warren, including the first houses built out at Fountain Gate. Assume it is present in the wet area sheeting and behind the tiles until testing by a NATA accredited laboratory says otherwise, and have removal done by a licensed asbestos removalist as a priced item of its own. The Narre Warren South estate housing built from 1999 onwards is clear of it.
What to do next
- Work out whether the layout changes. If it does, ask a private building surveyor whether a permit is needed before you accept a quote.
- Check the renovator’s registration on the Building and Plumbing Commission register and confirm the class covers bathroom work.
- Get the scope and the contract in writing, with the deposit inside the legal cap.
- Keep the plumbing compliance certificate and the Certificate of Electrical Safety with your house papers.
The checklist for choosing a renovator turns those into questions you can ask on site, and bathroom renovation cost in Narre Warren shows which band your job is likely to sit in. Every quote through the quote form is written and fixed for the scope described, with work done by registered and licensed trades.