The deck looks great. The garage conversion makes perfect sense. The extension is exactly what you wanted.
Then you read the contract.
No building permit.
That is when a building project that belonged to the previous owner can become something you need to deal with.
In August 2026, Prepared lawyers reviewed 330 Victorian contracts of sale.
31 of them, almost one in eleven, disclosed building works where the required permit wasn't in place.
The works ranged from decks and pergolas to extensions, carport enclosures and converted garages.
Most looked like perfectly ordinary parts of a home.
It’s a small detail that can make a big difference.
When you're inspecting a property, you're looking at what is there.
You don't necessarily see the building permit sitting behind it.
And you shouldn't have to be a building surveyor to know what questions to ask.
That's where the contract matters.
The Section 32 and other contract documents can reveal building work that isn't obvious from simply walking through the property.
In our August sample, the contracts disclosed:
Some contracts contained more than one issue.
The important point isn't the exact category. It's that the issue appeared in almost one in eleven contracts we reviewed.
Because building work doesn't become someone else's problem simply because someone else built it.
If you buy a property with an unapproved structure, you become the owner of that structure.
That doesn't necessarily mean you have to demolish it.
It doesn't mean the property is automatically unsafe.
And it doesn't mean the vendor has done something wrong.
But it does mean you need to understand what was built, when it was built, what approvals were required, and what paperwork exists.
The earlier you find that out, the more choices you have.
contracts involved owner-builder works
Of the 31 contracts we identified, 27 involved owner-builder works.
That makes sense.
Owner-builder projects are a common source of building work that requires closer attention to permits and documentation.
A previous owner may have built or substantially altered part of the property themselves.
Perhaps they added an extension.
Perhaps they enclosed a carport.
Perhaps they built a substantial deck.
Perhaps they converted an area of the house into something else.
Years later, you see a finished room.
The contract may tell a very different story.
Don't just ask, "Was it built properly?"
Ask:
"What approvals were required, and can I see them?"
Those are two different questions.
This is where the numbers become particularly interesting.
Of the 31 contracts, seven disclosed high-value or structural works without the expected permit.
These included things such as major extensions, structural work, slabs and significant roofing work.
These aren't cosmetic changes.
They're the sorts of projects where understanding the approval history matters.
If you're buying a house because you love the large extension at the back, you want to know more than whether the extension looks good.
You want to know whether the paperwork supports what you're buying.
The deck doesn't collapse.
The council doesn't send a letter.
Nobody complains.
The house changes hands.
One of the frustrating things about unpermitted work is that nothing may happen for years.
Then, years later, the issue can surface when the owner:
By then, the person who did the work may be long gone.
You own the property.
That's why the best time to investigate building work is before you buy it.
There are a few types of building work that deserve an extra look.
Particularly raised decks and decks with roofs or other substantial structures attached.
Especially where they're attached to the dwelling or form part of a larger extension.
An enclosed carport can look like a perfectly normal room from inside the house.
But enclosing it can involve more than putting up a few walls.
A converted garage can make an attractive extra bedroom, office or living area.
But there's a difference between a room that looks like a bedroom and a room that was approved to be used as one.
That distinction matters.
You don't need to become an expert in Victorian building regulations.
Start with the paperwork.
Look at the relevant building permit and owner-builder disclosures in the Section 32 and contract documents.
Don't just look for a yes or no. Read the details.
Walk through the house and ask yourself: Does what I'm seeing match what's been disclosed?
If there's an obvious extension, deck or conversion that doesn't appear anywhere in the paperwork, that's worth asking about.
A contract may refer to a certificate, report or other document. Make sure the document is actually there.
We've seen contracts where an important disclosure refers to an attachment that wasn't included with the documents provided for review.
Was it an owner-builder? A registered builder? When was it completed? What was done? What did it cost?
Those details can change what documentation should exist.
A building inspection and a legal contract review do different jobs.
Tell the inspector about any disclosed works so they can pay particular attention to them.
This is the key point.
Building problems are expensive to discover after settlement.
Contract problems are much easier to deal with while you're still deciding whether to buy.
This is where buyers need to be careful.
If the contract doesn't disclose building work, that doesn't necessarily mean there isn't any.
It may simply mean there is nothing to disclose.
But if you walk into the property and see a brand-new-looking extension, a converted garage or a substantial deck that clearly wasn't part of the original house, the absence of a disclosure is worth investigating.
A contradiction is a question.
And questions are much easier to ask before you've signed than after you've bought the property.
This is an important distinction.
A missing permit does not automatically tell you whether the building work is structurally sound.
Likewise, a permit doesn't automatically guarantee that every aspect of a building is perfect.
They're different questions.
A contract review can identify what the documents say and what appears unusual.
A building inspection can assess the physical condition of the property.
You may need both.
That's the part worth remembering.
When you're buying a house, you're not just buying the kitchen you can see.
And sometimes, you're buying a problem that was created years before you ever heard of the place.
Your advantage is finding that out while you still have a choice.
Our August sample found 31 affected contracts out of 330.
That's 9.4% — just under one in eleven.
But there's an important limitation.
Our figures are based on what was disclosed in the contracts we reviewed.
If building work wasn't disclosed, it doesn't appear in this dataset.
So this isn't a measure of how many Victorian homes actually contain unpermitted work.
It's a measure of how often our lawyers found the issue disclosed in the contracts presented to them.
That distinction matters.
And it's exactly why comparing the paperwork with what you can actually see is so important.
If we walked into a property and saw substantial building work, we'd want three things before signing:
Not because every unpermitted structure is a disaster.
Because you shouldn't buy uncertainty when you can investigate it first.
Before you buy the house, understand the paperwork behind it.
Send us your contract and a Prepared property lawyer will review it the same day, for free.
We'll identify the building work that's been disclosed, explain what it means and tell you what questions are worth asking before you commit.
Because it's much easier to investigate someone else's renovation before you own it.
Prepared lawyers reviewed 330 Victorian contracts of sale between 1 and 26 August 2026, across metropolitan Melbourne.
A finding was counted where a qualified reviewer identified the issue and it appeared in the published contract review.
The figures represent building work disclosed by vendors in the contracts and associated documents reviewed by Prepared. Undisclosed work is not captured by this analysis.
Some contracts contained more than one category of building work, so the categories cannot be added together to determine the total number of affected contracts.
This analysis is based on a single month's sample and should not be treated as a representative measure of all Victorian properties.