Short answer: sometimes yes—but only if you’re keeping the changes “cosmetic.” The moment you start moving walls, plumbing, or altering the layout, new approval is usually required.
In Sydney, combining a separate bathroom and toilet is a very common renovation idea. It sounds simple—knock down the dividing wall, open up the space, and suddenly you’ve got a bigger, more functional bathroom. But here’s the catch: that dividing wall is rarely just “a wall.”
If your plan involves removing or modifying a wall, even if it looks non-structural, you may need approval or at least certification. Walls can contain plumbing, ventilation ducts, or even play a role in fire separation—especially in apartments or semi-detached homes. Once structural or building performance elements are affected, the work must comply with the Building Code of Australia and may require a Complying Development Certificate (CDC) or Development Application (DA).
Then comes the plumbing question—which is where most surprises happen.
Combining spaces usually means relocating fixtures like the toilet pan, basin, or shower. Even small adjustments can require new pipework, changes to floor gradients, and updated waterproofing. These are not considered “cosmetic” works. In fact, plumbing changes must be carried out by licensed professionals and often require compliance certificates under regulations overseen by NSW Fair Trading.
Let’s make it practical.
If you’re simply updating finishes—new tiles, new vanity, same layout—you might not need approval. But if your idea of “combine” involves knocking down the wall and redesigning the space, then yes, you’re stepping into approval territory. And skipping that step can come back to bite you later, especially when selling or dealing with insurance claims.
There’s also another layer people forget: ventilation and waterproofing compliance. A combined bathroom must still meet moisture control and ventilation standards. Removing a wall without upgrading these systems can lead to condensation issues, mould, and long-term damage—things that don’t show up on day one but definitely show up later.
So what’s the smart move?
Before starting, have a licensed renovation professional assess your layout and confirm whether the wall is structural, what services are involved, and what approvals (if any) are required. A quick check at the beginning can save weeks of delays and thousands in rework.
Bottom line: combining a bathroom and toilet can add real value and improve usability—but only when it’s done properly. If it changes structure or layout, assume approval is needed and plan accordingly. It’s the difference between a smooth renovation… and a very expensive “oops.”
Contact us for bathroom renovation and kitchen renovation services in the following areas
Bondi, Manly,Epping, Mosman, Balmain,St Ives, Artarmon, Chatswood
