Build your bathroom budget in five steps
In short
Your bathroom renovation cost depends on the scope, location, existing condition and fixtures you choose. A cosmetic refresh, a full replacement in the same layout and a layout change need different budgets. This guide does not give a national price range: it has no verified current dataset that would make one reliable. To set your budget, get written quotes after a site inspection, add costs you will pay separately and reserve money for unexpected work.
Step 1
Choose the scope before asking for prices
Write down the room dimensions, what you will keep and what you will replace. Include any leaks, damaged surfaces or access problems. Photos help, but they cannot show the condition behind walls or under tiles.
These are planning categories, not price bands. A small bathroom with hidden damage can need more work than a larger room in sound condition.
Three bathroom renovation scopes
| Scope | What to include in the brief |
|---|---|
| Cosmetic refresh | Paint, accessories or selected fittings, with the layout and wet-area surfaces retained. Ask whether the work will disturb existing waterproofing. |
| Full replacement, same layout | Strip-out, surface preparation, waterproofing, tiling and new fixtures. Keeping locations does not mean old pipes or damaged framing can stay. |
| Layout or structural change | Moving plumbing points, changing walls or expanding the room. Ask about design, structural advice, approvals and changes to services. |
Step 2
Account for the trades and fixtures
Depending on the scope, the work may involve a builder or renovation contractor, plumber, electrician, waterproofer, tiler, carpenter, cabinetmaker, glazier and painter. Ask who coordinates the work and which trades are included in the price.
Choose fixture models and tile finishes before signing where possible. A prime cost item is an allowance for a fixture or fitting that has not been fully selected or priced. A provisional sum is an estimate for work whose cost is not yet known. Either can change the final bill.
Step 3
Check waterproofing and permissions early
Waterproofing is the system that keeps water out of the building beneath wet-area finishes. Ask what areas will be treated, how the surface will be prepared and what records you will receive. Confirm the required credentials for that work with your state or territory regulator.
Licence, permit, contract and insurance requirements vary by jurisdiction and project. Check with your council or building certifier before work starts. In a strata property, check the owners corporation or body corporate process too. NSW, for example, treats renovations involving waterproofing as major renovations requiring strata approval.
Step 4
Compare quotes for the same bathroom
Give each contractor the same brief and selections, and arrange a site visit. Ask for more than one written quote. If a price is much lower, identify the different inclusions, allowances or exclusions before deciding.
Use the checklist below to ask each company what its price covers.
Step 5
Keep a reserve for unexpected work
Contingency is money set aside for costs you cannot confirm before work starts. Ask the contractor what remains unknown after inspection, such as concealed water damage or the condition of old pipes, and how those risks affect the reserve you need. There is no single percentage suitable for every bathroom.
Calculate your available budget against the quoted work, your separate purchases and fees, and that reserve. If this is your only bathroom, also plan and price any temporary arrangements while it is out of use.
Sources and useful links
Sources checked 6 October 2026
- YourHome: renovations and additions
Australian Government guidance on renovation planning and approvals; not a current bathroom price dataset.
- Consumer Affairs Victoria: building contracts checklist
Explains fixture selections, prime cost items and provisional sums. Legal requirements on this page apply to Victoria.
- QBCC: seeking and comparing quotes
Queensland guidance on site visits, quote inclusions, hidden costs and payment terms.
- QBCC: waterproofing guidance for homeowners
Queensland-specific guidance on licensed waterproofing work and documenting its scope.
- NSW Government: strata renovation rules
NSW approval categories, including work involving waterproofing. Other jurisdictions have different processes.
- Victorian Government: unexpected costs or going over budget
Explains contingency and the importance of planning for unforeseen costs.
