What's Included
A typical bathroom plumbing renovation covers:
- Rough-in plumbing (first fix): new hot and cold supply lines, waste pipes, and drainage connections to AS/NZS 3500:2025 Plumbing and Drainage (updated April 2025, mandatory from October 2025). Budget ~$1,500–$4,000 for rough-in.
- Fixture installation (second fix): fitting the toilet, basin, shower, and bath after tiling is complete. Budget ~$1,000–$2,500 for fit-off. Fixtures supplied by the homeowner or quoted separately.
- Isolation valves: individual shut-offs for each fixture, allowing future maintenance without turning off water to the whole house.
- Compliance testing: pressure testing supply lines and checking drainage falls meet code.
- Two-stage visits: rough-in before waterproofing and tiling, then fit-off after tiling is done. Plan for two separate plumber visits, typically 2–4 weeks apart.
Not typically included: waterproofing membrane (~$1,800–$3,500, separate trade, must comply with AS 3740:2021), tiling (~$4,000–$10,000), electrical work (~$1,500–$4,000), vanity cabinetry, or fixture supply unless quoted as a package.
Fixtures: What They Cost
Understanding fixture pricing by tier helps you evaluate quotes and control the budget. Fixtures are typically 30–40% of a full renovation cost.
| Fixture | Budget | Mid-Range | Premium | Notes |
|---|---|---|---|---|
| Toilets | $400–$500 (Caroma Profile II close-coupled) | $550–$700 (Caroma Luna Cleanflush, rimless) | $650–$2,000+ (wall-hung from Caroma, Villeroy & Boch, Duravit) | Wall-hung toilets need a concealed cistern frame (~$300–$600 extra) plus wall reinforcement |
| Vanities (wall-hung, 900mm) | ~$400+ (Highgrove, available at Bunnings) | $1,200–$2,250 (Timberline, ADP) | $1,500–$3,500 (Marquis, ADP made-to-order) | Australian brands offer made-to-order options with 6–8 week lead times. Freestanding vanities are simpler to install ($800–$2,500) |
| Tapware (full bathroom) | ~$120/piece (Dorf, Methven); ~$600 total | $200–$400/piece (Phoenix Tapware, Caroma); ~$800–$1,200 total | $500–$900+/piece (Sussex Taps, 30+ finishes); ~$1,500–$2,000+ total | Full bathroom = basin mixer, shower mixer, bath spout if applicable |
| Bathtubs | $250–$800 (built-in acrylic) | $1,700–$3,000 (freestanding acrylic, Decina) | $3,800–$7,500+ (Victoria + Albert, QUARRYCAST composite, 25-year guarantee) | |
| Shower screens | $400–$1,200 installed (framed) | $600–$1,800 installed (semi-frameless) | $800–$2,500 installed (frameless, 10mm glass) |
The Renovation Sequence
A bathroom renovation involves 5–7 separate trades in a strict sequence. Getting the order wrong causes delays and defect risk.
- Demolition (1–2 days, ~$500–$3,000). Strip tiles ($50–$150/m2), remove fixtures, remove wall linings. Asbestos testing recommended for pre-1990 homes (~$400 for professional inspection).
- Plumbing rough-in (1–2 days). Supply and waste pipes installed in walls and floor.
- Electrical rough-in (half to 1 day). Wiring for exhaust fan, lighting, power points, heated towel rail. Must comply with AS/NZS 3000 wet area zones: Zone 0 (inside shower base) allows only 12V equipment; Zone 1 (up to 2.5m above floor) prohibits power points; Zone 2 (0.6m beyond Zone 1) requires RCD protection for all outlets.
- Waterproofing (1 day + 24–48hr cure). Membrane applied to shower floor, walls to 1,800mm in shower zone, and at least 100mm up all bathroom walls. Timber or upper-level floors require full-floor waterproofing under AS 3740:2021.
- Waterproofing inspection (mandatory hold point). A certifier must inspect and approve the membrane BEFORE tiling begins. If it fails, the waterproofer strips and re-applies. This hold point adds 3–5 days if re-work is needed.
- Tiling (3–7 days). The most time-intensive stage. Wall and floor tiles installed and grouted.
- Fit-off (1–2 days). Plumber installs toilet, basin, shower, taps. Electrician connects fan, lights, towel rail. Painter finishes ceiling and exposed walls.
Total timeline: 3–6 weeks on-site. Custom vanities and stone tops can add 6–8 weeks of lead time before work starts.
What Affects the Cost
- Layout changes. Keeping fixtures in their existing positions is significantly cheaper than re-routing waste and supply lines. Moving a toilet on a concrete slab requires slab cutting (~$3,000–$5,000 for the toilet alone). A full layout change with all fixtures relocated can add $5,000–$10,000+ to the plumbing scope.
- Number of fixtures. A full bathroom (toilet, basin, shower, bath) requires more pipe runs, connections, and labour than a compact ensuite (toilet, basin, shower).
- Floor construction. Concrete slab requires diamond-saw cutting for any fixture relocation. Timber floors (common in pre-war homes and Queenslanders) allow easier sub-floor access for pipe runs.
- Wall type. Double-brick (common in Melbourne and Adelaide) is harder and slower to chase pipes through than timber-framed plasterboard. Stone walls in Adelaide cottages (300–500mm thick) are the most difficult and expensive.
- Pipe material. Replacing old galvanised steel or lead pipes with modern PEX or copper adds cost but is often required in pre-1970 homes. Cast iron waste pipes in Victorian-era terraces should be replaced with PVC during the renovation.
- Hobless (walk-in) shower vs hob shower. Hobless showers cost 20–35% more (~$3,200–$10,000 vs ~$1,300–$3,000) due to more complex drainage falls and additional waterproofing. They require precise floor grading by the tiler and waterproofer.
- Electrical add-ons. Heated towel rail (~$350–$1,800 installed), underfloor heating (~$800–$4,000 for a bathroom), exhaust fan with humidity sensor (~$400–$900 installed).
A fixture-in-place renovation in a timber-framed home with sub-floor access and budget fixtures sits toward $3,000. A full layout change on a concrete slab in a double-brick home, with premium fixtures, hobless shower, heated towel rail, cast iron pipe replacement, and slab cutting pushes toward $8,000.
City and Regional Price Comparison
City-level differences: Sydney (NSW) sets the baseline for bathroom plumbing renovation costs. Melbourne tracks within 5% of Sydney pricing. Brisbane can be slightly cheaper due to the prevalence of high-set Queenslanders with accessible sub-floor plumbing that reduces labour time. Perth and Adelaide tend to run 10–15% higher, driven by smaller plumber pools and regional material costs.
Home warranty insurance thresholds vary significantly: NSW requires coverage above $20,000, VIC above $16,000, QLD above $3,300, WA above $20,000, and SA above $20,000 (increased from $12,000 in November 2025). Most mid-range bathroom renovations will cross these thresholds when all trades are combined.
Suburb and regional-level differences: Construction type varies significantly within each city and directly impacts plumbing complexity. Inner-city terraces in Paddington (Sydney) or Fitzroy (Melbourne) typically have cast iron waste pipes, narrow footprints, and limited access, pushing costs toward the upper end. Older stone cottages in Norwood or Prospect (Adelaide) have thick masonry walls that are slow and expensive to chase pipes through. High-set Queenslanders in Woolloongabba or Paddington (Brisbane) have open sub-floor space that makes pipe runs straightforward. New-build estates in Oran Park (Sydney), Tarneit (Melbourne), or Springfield (Brisbane) have modern PEX plumbing and timber-framed walls on concrete slab, making fixture-in-place renovations the simplest jobs.
Common Cost Blowouts
The most expensive surprises in bathroom renovations are hidden behind the tiles you just demolished:
- Water damage behind tiles. Rotted timber framing, termite damage, or mould growth invisible until demolition. Can escalate a cosmetic renovation into structural repair. Budget a 10–20% contingency.
- Asbestos (pre-1990 homes). Flat asbestos cement sheet behind tiles, vinyl floor tiles with asbestos adhesive. Licensed removal runs ~$1,500–$3,000 for a small bathroom. Roughly one-third of Australian homes built before 1990 contain asbestos somewhere.
- Non-compliant previous waterproofing. Faulty waterproofing is one of the most common building defects in Australia, causing as much damage as termites. If the old membrane fails inspection, it must be completely stripped and re-done before tiling.
- Plumbing that does not meet current code. Once walls and floors are opened up, existing plumbing must be brought to current AS/NZS 3500 standard. Galvanised steel, lead supply pipes, or inadequate drainage falls trigger mandatory upgrades.
How We Calculate
Estimates are based on current licensed Plumber rates adjusted for each state, standard material costs, and typical renovation complexity. All prices include GST. Ranges reflect the difference between a like-for-like fixture swap and a full layout change requiring slab cutting and new pipe runs. The plumbing figures on this page cover the plumbing trade only. Waterproofing, tiling, and electrical costs are separate.