You've done the research, compared three quotes, and settled on a kitchen renovation budget of $30,000. Six weeks later, you're staring at a bill closer to $45,000 and wondering where it all went wrong.

You're not alone. Our pricing data across Australian cities shows kitchen projects exceed the original quote by 20–40% more often than not. The reason isn't dodgy tradies — it's that the standard quote doesn't cover everything you'll actually need.

20–40%
Typical budget overrun on kitchen renos
4–8 wks
Average duration of a full kitchen renovation
3+
Quotes you should always get
15–20%
Contingency you should build in

Where a $35k kitchen quote actually ends up

Let's track a real scenario. You accept a $35,000 quote for a full kitchen renovation — new cabinetry, benchtop, appliances, tiling, plumbing and electrical. Here's what the final bill typically looks like once the hidden costs surface.

Cost itemAmount
Original builder quote (cabinets, benchtop, tiling, labour)$35,000
Temporary kitchen setup (8 weeks of meals, bar fridge, microwave)$1,400
Asbestos testing + removal (splashback sheeting)$2,800
Switchboard upgrade for induction cooktop$3,200
Structural engineer (load-bearing wall assessment)$900
Council building permit + certifier$1,800
Appliance rush delivery (rangehood 4 weeks late)$650
Finishing touches (repainting, flooring transition, new pantry door)$2,400
Actual total$48,150

That's a 37.5% blowout — and every single item on that list is common. Let's break down each one so you know what to expect.

1. Temporary kitchen setup — $800–$2,000

Your kitchen will be completely unusable for the duration of the renovation. No sink, no cooktop, no fridge in its usual spot. Most families underestimate how expensive it is to live without a kitchen for 4–8 weeks.

The costs accumulate in ways you don't expect: takeaway meals and restaurant dinners ($50–$100/day for a family of four), a bar fridge ($150–$300 to buy), a microwave and electric kettle in the laundry, paper plates and disposable cutlery, and the sheer inconvenience tax of washing dishes in the bathroom sink.

💡 Pro tip Set up a proper temporary kitchen before demolition starts. A trestle table in the garage with a bar fridge, microwave, toaster oven, and electric kettle will save you hundreds in takeaway over the project duration. Some families also borrow a camping stove for basic cooking.

2. Asbestos discovery — $1,500–$5,000+

If your home was built before 1990, there's a real chance your kitchen contains asbestos. It commonly hides in splashback sheeting (fibro), vinyl flooring underlay, textured ceilings, and the backing of old wall tiles.

Testing costs $150–$300 per sample. But removal is where the money goes — and it's non-negotiable. In every Australian state and territory, asbestos removal over 10m² must be done by a licensed asbestos removalist. Your builder will legally stop work until it's handled.

⚠️ Critical Never attempt to remove asbestos yourself. It's illegal in most states for quantities over 10m², and even small amounts release microscopic fibres that cause mesothelioma. Licensed removal in NSW and Victoria typically costs $1,500–$3,000 for a kitchen-sized area. In Queensland, costs can be slightly lower. Budget for it, and get it tested before you sign the building contract.
Testing
$300
Small removal
$1,500
Medium removal
$3,000
Extensive removal
$5,000+

3. Electrical and plumbing upgrades — $2,000–$8,000

This is where budgets blow out most dramatically. The plumbing and electrical in your existing kitchen were designed for your existing layout. Change anything — and you almost certainly will — and the costs escalate fast.

Plumbing traps: Moving the sink even 300mm requires modifying drainage falls under the floor, which means pulling up flooring. Relocating a dishwasher to the other side of the kitchen adds a new water supply line and waste connection. Adding a pot-filler tap above the cooktop means running a new water line through the wall cavity.

Electrical traps: Switching from gas to induction is increasingly popular, but your switchboard may not handle the 32-amp circuit an induction cooktop requires. A switchboard upgrade runs $2,000–$4,500. Even adding under-cabinet LED lighting, extra power points, or a built-in microwave circuit adds $200–$600 per point.

Common upgradeTypical cost
Move sink <1 metre (modify drainage falls)$800–$2,000
Relocate dishwasher (new supply + waste)$500–$1,200
Switchboard upgrade for induction$2,000–$4,500
Additional power point (per point)$200–$400
Under-cabinet LED lighting (full run)$400–$900
Relocate gas line for cooktop$300–$800
New rangehood ducting through roof$600–$1,500
💡 Pro tip Ask for a separate, detailed plumbing and electrical scope before signing the building contract. Many builders include a vague "plumbing and electrical allowance" of $3,000–$5,000 that barely covers the basics. Get the plumber and electrician to walk through the design and price it properly first.

Getting a kitchen quote? Check what others are paying in your area before you sign.

Check Kitchen Renovation Costs in Your City →

4. Structural surprises behind walls — $500–$8,000

Demolition day is when kitchens reveal their secrets. Once walls come down, you may find water damage from slow leaks you never noticed, termite trails or damage to framing, non-compliant wiring or plumbing from previous renovations, or the uncomfortable discovery that the wall you wanted to remove is load-bearing.

A structural engineer assessment costs $500–$1,500. If the wall is load-bearing, you'll need a steel beam (RSJ) installed to carry the load, which adds $2,000–$6,000 in materials and labour. The total remediation package for structural issues typically runs $2,000–$8,000.

✓ Good sign in a quote

Builder includes a contingency line item (usually 5–10% of the project value) specifically for "unforeseen structural or compliance issues discovered during demolition."

✗ Red flag in a quote

No mention of contingency. Fixed price with no exclusions listed. Builder says "we'll deal with anything that comes up" without putting a number on it.

5. Council permits and certifications — $500–$4,500

Not every kitchen renovation needs council approval. But many do, and the rules vary by state and council area. Generally, you'll need a permit if you're changing the building footprint (even slightly), removing or altering structural walls, significantly relocating plumbing, or making changes that affect fire safety or accessibility.

Building permits range from $500–$2,500 depending on your council and the scope of work. On top of that, you'll need a building surveyor or private certifier ($800–$2,000) to inspect the work at various stages and issue a compliance certificate when it's done.

⚠️ Don't skip this Some homeowners skip permits to save money. This is a costly mistake when you sell. Uncertified structural work must be disclosed, and buyers (or their conveyancers) will discover it. You may be forced to retrospectively certify the work — which often costs more than getting the permit in the first place — or discount your sale price.

6. Appliance delivery timelines — $500–$2,500

Your builder is on schedule. The cabinets are in, the benchtop is templated. Then you learn the Italian rangehood has a 12-week lead time, or the specific oven model you chose is backordered until next quarter.

The consequences are expensive. Idle tradies charge $400–$800 per day, because they've blocked out your job in their calendar and can't take other work. Rush shipping adds $500–$2,000 depending on the appliance and origin. Or worse, you compromise on a different model and it doesn't fit the cabinetry cutout — meaning modification costs.

💡 Pro tip Order all appliances the moment you sign the building contract — not when demolition starts. Check lead times before you finalise the kitchen design. Domestic brands (Fisher & Paykel, Westinghouse) typically ship in 1–2 weeks. European imports (Smeg, Miele, ILVE) can be 6–16 weeks. If a specific model has a long lead time, ask your kitchen designer to confirm the cutout dimensions match alternative models as a backup.

7. Scope creep and finishing touches — $2,000–$5,000

This is the sneakiest hidden cost because it feels like a series of small, reasonable decisions rather than a budget blowout. Once the new kitchen starts taking shape, you'll notice everything around it that suddenly looks old or mismatched.

Common scope creep items and their costs:

AdditionCost
Repaint walls and ceiling in adjoining living area$800–$1,500
New flooring transition strip / threshold$150–$400
Replace pantry door to match new cabinetry$300–$600
New light fitting in dining area$200–$500
Window treatment update$300–$800
Extended splashback / feature tile$400–$1,200
Soft-close drawer upgrades (per drawer)$30–$60

Each one is individually reasonable. Together, they add $2,000–$5,000 to your final bill. The way to manage this is to expect it: mentally allocate a "finishing touches" budget from day one.

Your pre-renovation checklist

Before you sign anything, make sure you've covered these bases:

The real budget formula

Take the quote you've accepted. Add 15–20%. That's your real budget. If you come in under, celebrate. If you hit the ceiling, you planned well.

A $35,000 quote means mentally committing to $42,000. A $50,000 quote means $60,000. This isn't pessimism — it's how experienced renovators budget. The homeowners who feel "ripped off" at the end are almost always the ones who treated the original quote as a fixed price rather than a starting point.

For a full breakdown of kitchen renovation costs by city — including cabinetry, benchtops, appliances, and labour — see our Kitchen Renovation Cost Guide.