How to Quote a Bathroom Renovation: The Complete Breakdown
· 7 min read
Bathroom renovations are one of the most profitable — and most headache-prone — jobs in the trade. There are multiple trades involved, tight spaces, hidden problems, and clients who often don't understand why it costs as much as it does. Getting your quote right from the start is the difference between a smooth job and a bitter dispute at handover.
Here's how to approach a bathroom renovation quote, trade by trade, so nothing slips through the cracks.
Demolition and strip-out
Before anything new goes in, the old stuff has to come out. Demolition includes removing the existing vanity, toilet, shower screen or bath, tiles, and any old fixtures. Don't forget skip hire or disposal costs — these add up quickly and are often forgotten. If you're not doing the demo yourself, get a price from a labourer or demo contractor and include it as a line item. Also flag the risk of asbestos in older homes (pre-1990s) as a potential exclusion or separate cost if testing is required.
Waterproofing
Waterproofing is non-negotiable and often underquoted. It needs to be done to code, and in most states it must be completed by a licensed waterproofer with a certificate of compliance. Include the cost of the membrane, all materials, and the labour. Factor in drying time — waterproofing adds at least a day or two to the job timeline. If you're coordinating trades, this needs to happen before tiling, so sequence it correctly in your schedule.
Plumbing
Plumbing is one of the biggest variables in a bathroom renovation. A like-for-like replacement (same position, same fixtures) is straightforward. Moving drainage or shifting the toilet pan location is a completely different conversation — it may involve cutting concrete, relining walls, or rerouting pipes through joists. Quote these scenarios separately. If you're a plumber quoting the whole job, be specific about what's included: rough-in, fixtures, and final connections. If you're a builder coordinating a plumber, get their written quote and include it in your own with a clear margin.
Tiling
Tiling is both labour and materials, and both need to be broken down. For labour, calculate the total square metreage of floor and wall tiling. Factor in any feature walls, niche shelves, or tricky cuts around fixtures — these all add time. For materials, tile costs vary enormously: budget tiles start around $30–$50/m², premium tiles can hit $150/m² or more. Always specify the tile allowance in your quote (e.g., "Tiling allowance of $60/m² supply — client to select within budget") so you're not absorbing the cost if they pick something expensive.
Fixtures and fittings
Vanities, toilets, shower screens, tapware, towel rails, mirrors — these are often the biggest wildcard in a bathroom renovation budget. Some clients want builder's-grade; others have their hearts set on a $2,000 freestanding bath. The safest approach is to quote using a nominated fixture allowance and itemise each piece separately. That way the client can upgrade or downgrade individual items without blowing up your entire quote. Use instanttradequote to list each fixture as its own line item — it makes the quote far easier for the client to understand and adjust.
Electrical
Most bathroom renovations require at least some electrical work: a new exhaust fan, a heat lamp, a shaving cabinet with lighting, or upgrading to a safety switch. In many regions, all bathroom electrical work must be done by a licensed electrician. If you're not the electrician, get a subcontractor quote and include it. Common items to price: exhaust fan installation, downlight fitting, heated towel rail wiring, and any new circuits required by the scope.
Plastering and painting
If walls are being opened up or damaged during demo, factor in plasterboard repairs and plastering. Don't leave this out — it's easy to forget and clients expect it to be included. Painting a wet area also requires specific paint products designed to handle moisture. Include the product cost, number of coats, and whether any preparation (priming, filling) is needed.
Contingency
Always include a contingency — typically 10–15% of the total job cost — for older properties or any job where you can't see what's behind the walls. Call it out clearly in your quote: "10% contingency for unforeseen works (leaking pipes, structural issues, asbestos, etc.). Unused contingency will be credited on final invoice." This manages expectations upfront, protects your margin, and positions you as the professional who's thought of everything.
Pulling it all together
A bathroom renovation quote should be detailed enough that the client can see exactly what they're getting, but organised enough that it doesn't overwhelm them. Group costs by trade or phase, include your payment terms (a deposit, a progress payment, and a final payment at completion is standard), and be clear about your timeline. A well-structured quote wins jobs and prevents disputes — and a tool that lets you build that structure quickly means you spend less time quoting and more time working.