Bathroom renovations are one of the most common home improvement projects in Melbourne — and plumbing is almost always the biggest single trade cost. Getting the plumbing scope right from the start prevents costly rework and avoids the issues that come with unlicensed plumbing work.
What Plumbing Work Is Involved in a Bathroom Renovation?
- Relocation of fixtures: If you’re moving the toilet, shower, bath, or basin from their current positions, drainage and supply pipes need to be moved — this is significant plumbing work and requires opening floors or walls
- Like-for-like replacement: Replacing fixtures in the same position is much simpler — new connections to existing supply and drain points
- New shower installation: Drain installation, waterproofing coordination, and hot and cold supply connections
- Tapware replacement: Replacing mixers, showerheads, and basin taps to existing supply points
- Hot water tempering valve: Required by Victorian law for new shower installations in bathrooms used by the elderly or children
What Requires a Licensed Plumber in Victoria?
All of the following require a VBA-licensed plumber and a Certificate of Compliance:
- Any drainage work (new drain, relocated drain, drain connection)
- Water supply pipe work (new pipes, relocated pipes, isolating valves)
- Installing or replacing fixtures connected to supply or drainage
- Installing or replacing hot water connections
- Tempering valve installation
DIY plumbing beyond washer replacement in an existing fitting is illegal in Victoria and will void your home insurance for any resulting damage.
Typical Plumbing Costs for a Melbourne Bathroom Renovation
- Like-for-like fixture replacement (same positions): $800–$2,000 plumbing labour
- Full bathroom reconfiguration (relocated fixtures): $3,000–$8,000+ plumbing labour, depending on floor/wall access
- New shower drain installation: $500–$1,200
- Tapware supply and installation: $300–$800 per fixture (mid-range tapware)
Coordinating Plumbing with Other Trades
The sequence matters in bathroom renovations:
- Plumber does rough-in work (pipes to location) before tiling
- Waterproofing is done after rough-in but before tiles
- Plumber returns for fit-off (connecting fixtures) after tiling is complete
A common and expensive mistake is starting tiling before plumbing rough-in is signed off. Any change after tiling is a costly rip-out.
Sedcon Plumbing handles bathroom renovation plumbing across Melbourne — rough-in, fit-off, and everything in between. Call 0468 013 012 | VBA Lic. 120392