One of the first questions every homeowner asks when considering a bathroom renovation is: how much will it cost?
The honest answer is: it depends. But "it depends" isn't helpful unless you understand what it depends on — and why those factors matter.
This guide breaks down realistic bathroom renovation costs in Australia, explains what drives price variation, and gives you the framework to budget properly before you start talking to builders.
What does a bathroom renovation cost in Australia?
The ranges below reflect typical costs for bathroom renovations across Australia in 2025. They're indicative — actual costs depend on size, location, materials, and site conditions — but they give you a realistic starting point.
Basic refresh
$8,000 – $15,000
Cosmetic updates only — new vanity, tapware, toilet, paint. No layout changes, no waterproofing work, existing tiles retained or painted.
Mid-range renovation
$15,000 – $30,000
New tiles, fixtures, vanity, shower screen, and full waterproofing. Layout unchanged. Most standard Australian bathroom renovations fall here.
Full renovation
$25,000 – $50,000+
Strip to frame, new waterproofing membrane, full fit-out with quality materials. May include layout changes, plumbing relocation, or structural work.
Premium renovation
$50,000+
Large bathrooms, high-end materials (stone, custom joinery, heated floors), complex layouts, or significant structural changes.
These are indicative ranges only. Your actual cost will depend on the specific factors covered below. Always get itemised quotes from licensed builders before budgeting.
What drives the cost of a bathroom renovation?
Size of the bathroom
Larger bathrooms require more tiles, more waterproofing membrane, more labour, and often more fixtures. A compact ensuite and a large main bathroom can differ by $10,000–$20,000 in cost even with identical materials and finishes. Always get quotes based on actual measurements, not rough estimates.
Scope of work — cosmetic vs structural
A cosmetic refresh (new vanity, tapware, paint) is fundamentally different from a full strip-out and rebuild. The moment you change the layout, relocate plumbing, or need to address waterproofing failures, costs increase significantly. Be clear with yourself — and your builder — about what you actually need, not just what you want.
Material choices — tiles, vanity, fixtures
Materials are one of the most variable cost drivers. Entry-level tiles can cost $30–$60/m²; premium stone or large-format tiles can reach $150–$300/m² or more. The same applies to vanities, shower screens, tapware, and baths. A mid-range renovation with premium materials can easily push into the full-renovation price bracket.
Waterproofing requirements
Proper waterproofing is non-negotiable in any bathroom renovation — and it's one of the areas where corners are most commonly cut. In Australia, waterproofing must comply with AS 3740. The cost of doing it properly is modest relative to the total renovation; the cost of doing it poorly — water damage, mould, structural rot — can be catastrophic. Any quote that doesn't explicitly include waterproofing should be questioned.
Plumbing and electrical changes
If your renovation involves moving a toilet, relocating a shower, or adding a bath where there wasn't one, you're looking at significant plumbing costs — potentially $3,000–$8,000 or more depending on complexity. Electrical changes (new lighting, exhaust fans, heated towel rails) add further. These costs are often underestimated in early budget conversations.
Hidden issues found during strip-out
This is the factor most homeowners don't budget for — and the one that causes the most budget blowouts. When tiles come off and walls are opened up, builders sometimes find mould, rot, failed waterproofing, non-compliant old plumbing, or structural damage. These issues must be addressed before the renovation can proceed. A 10–15% contingency budget is strongly recommended for this reason.
Builder quality and project management
The cheapest quote is rarely the cheapest outcome. A builder who cuts corners on waterproofing, uses substandard materials, or manages the project poorly can cost you significantly more in remediation than you saved upfront. Builder quality — their process, their communication, their accountability — is a cost factor that doesn't appear on the quote but absolutely affects the final result.
What should always be included — and what's often skipped
Three items should appear in every bathroom renovation quote, regardless of scope: proper waterproofing, demolition and waste disposal, and waterproofing certification. These are not optional extras — they're fundamental to a compliant, durable renovation. If they're absent from a quote, ask why.
Waterproofing is the most commonly skimped item in low-cost bathroom quotes. Some builders apply a minimal membrane that meets the letter of the standard but not the spirit — or skip it entirely in areas they assume won't be inspected. A waterproofing certificate from a licensed waterproofer is the only way to verify this was done properly.
Demolition and disposal is another area where quotes vary. Some builders include full strip-out and skip bin hire; others quote only for the installation work and expect you to arrange disposal separately. This can add $1,000–$3,000 to a project if it's not included.
When comparing quotes, look for these items explicitly. A quote that doesn't mention waterproofing, disposal, or certification isn't necessarily cheaper — it may simply be hiding costs that will appear later.
Watch for "allowances" in quotes
Some quotes include line items like "tile allowance — $50/m²" rather than a fixed cost. This means the actual cost will depend on what you choose — and if your selection exceeds the allowance, the difference is added to your bill. Allowances are not fixed prices. Ask your builder to replace allowances with actual costs based on your confirmed selections before you sign.
Fixed-price quotes vs quotes with allowances
A fixed-price quote commits the builder to a total cost for a defined scope of work. Every element — tiles, waterproofing, labour, fixtures, disposal — is priced based on your actual selections. What you're quoted is what you pay, unless you request changes or genuinely unforeseen conditions arise during the build.
A quote with allowances is different. An allowance is a placeholder — a budget figure for an item that hasn't been fully specified yet. Common allowances include tiles, tapware, and vanities. The problem is that allowances make it very easy to compare quotes on paper while the actual costs remain unknown. A quote with a $40/m² tile allowance and a quote with a $90/m² tile allowance look similar until you choose your tiles.
Allowances also create a mechanism for budget blowouts. If your selections exceed the allowance — which is common, because allowances are often set conservatively — the difference is added to your contract price. By the time you discover this, work may already be underway.
The safest approach: make your material selections before you finalise your quote, and ask your builder to replace all allowances with fixed costs based on those selections. This is how a genuinely fixed-price quote works — and it's the only way to compare quotes accurately. For more on this, see our guide on how our renovation process works.
How to set a realistic bathroom renovation budget
A realistic budget starts with clarity about what you actually want — not what you hope to spend. Here's a practical framework:
Start with the outcome, not the number.
Define what you want the renovation to achieve — a fully waterproofed, retiled bathroom with a new shower and vanity is a different project from a cosmetic refresh. Be specific about scope before you ask for quotes.
Get at least 2–3 itemised quotes.
A single quote gives you no basis for comparison. Multiple itemised quotes let you see where costs differ — and why. If one quote is significantly lower than the others, ask what's been left out.
Include a 10–15% contingency.
Hidden issues found during strip-out — mould, rot, failed waterproofing, non-compliant plumbing — are common and must be addressed. A contingency budget means you're prepared for this, not caught out by it.
Ask specifically what is and isn't included.
Before you sign anything, confirm: Is waterproofing included? Is demolition and disposal included? Are all fixtures and fittings priced at your actual selections? Are there any allowances that could change the final cost?
What Japan Homes includes in every bathroom renovation quote
Every Japan Homes bathroom renovation quote is fixed-price and fully itemised — waterproofing, demolition, disposal, tiling, fixtures, labour, and certification are all included and individually costed. We don't use allowances for items that can be specified upfront. If you've made your material selections before we quote, the number we give you is the number you pay — unless you request changes or something genuinely unexpected is found during the strip-out, in which case we document it, explain the options, and get your approval before proceeding.
We work this way because it's the only approach that's genuinely fair to the homeowner. A quote that hides costs in allowances or excludes waterproofing isn't a lower price — it's an incomplete one. If you'd like to understand more about how we approach the quoting and renovation process, our FAQ page covers the questions we're asked most often.
Getting the budget right from the start
Knowing the realistic cost range for a bathroom renovation — and understanding what drives variation within that range — gives you a significant advantage before you start speaking to builders. You'll know what questions to ask, what to look for in a quote, and what warning signs to take seriously. The homeowners who get the best outcomes from renovation projects are almost always the ones who did this groundwork first.
Want an accurate quote for your bathroom renovation?
We provide clear, itemised, fixed-price quotes after assessing your bathroom — no guesswork, no surprises.
Book a Free Consultation