How Much Does a Knockdown Rebuild Cost in Australia? (2026)

The most common question from homeowners considering a KDR is: "What will it actually cost?" The honest answer is: it depends. But here's a realistic breakdown to help you budget.

The Major Cost Components

1. Demolition ($15,000–$35,000)

Demolition costs vary by house size, materials (asbestos adds significant cost), and access. A standard 3-bedroom brick veneer house in Sydney typically costs $18,000–$25,000 to demolish including skip bins and site clean-up. Asbestos removal can add $8,000–$20,000 depending on extent.

2. Construction ($250,000–$700,000+)

The build cost is the largest variable. As a rough guide:

• Budget project home: $1,800–$2,200/m²
• Mid-range custom home: $2,500–$3,500/m²
• High-end custom: $4,000–$6,000+/m²

A 250m² home at mid-range would cost $625,000–$875,000 to build.

3. Professional Fees ($20,000–$60,000)

These include architect or draftsperson ($8,000–$25,000), town planner ($5,000–$15,000), structural engineer ($3,000–$8,000), and private certifier ($3,000–$6,000).

4. Council and Government Fees ($5,000–$20,000)

DA lodgement fees vary by council and project value. Expect $3,000–$12,000. Contributions levies (Section 7.11 in NSW) can add significantly in growth corridors.

5. Landscaping and External Works ($15,000–$50,000)

Often underestimated. Driveway, fencing, lawn, garden, letterbox, clothesline — the list adds up quickly.

State-by-State Build Cost Summary

All figures are per m² of floor area and reflect 2026 market rates. Budget = project/volume builder; Mid-range = custom or semi-custom; Premium = architect-designed, high-specification finish.

State	Demolition	Budget (per m²)	Mid-range (per m²)	Premium (per m²)
NSW (Sydney)	$18,000–$30,000	$1,900–$2,400	$2,800–$3,800	$4,500–$7,000+
VIC (Melbourne)	$15,000–$25,000	$1,800–$2,300	$2,600–$3,600	$4,200–$6,500+
QLD (Brisbane)	$12,000–$22,000	$1,700–$2,200	$2,400–$3,200	$4,000–$6,000+
WA (Perth)	$12,000–$20,000	$1,600–$2,100	$2,200–$3,000	$3,800–$5,500+

Note: These are indicative ranges only. Final costs depend on design complexity, site conditions, materials selected, and current builder availability. Always obtain 2–3 fixed-price tenders before committing.

The Biggest Cost Variables

Three things move the number most: size of the new home, level of finish, and site conditions (slope, soil type, services). Always get a soil test done early — reactive clay or rock can add $20,000–$50,000 to your slab cost.

Getting an Accurate Quote

The only way to get a firm number is to have your design completed, then get 2–3 fixed-price tenders from builders. Never commit to a builder based on a preliminary estimate alone.