How Much Does a Custom Home Cost in the Illawarra?
The short answer: between $3,000 and $6,500+ per square metre for construction, depending on your design complexity and finish level. A 250m² home with mid-range finishes will cost roughly $800,000–$1,100,000 to build (excluding land).
But that number means nothing without context. Below, we break down exactly where your money goes and where most people get caught out.
But that number means nothing without context. Below, we break down exactly where your money goes and where most people get caught out.
Construction Cost Per Square Metre (2026 Illawarra Rates)
These are the rates we are quoting in 2026 for custom homes in the Wollongong, Shellharbour, and Kiama local government areas:
- Standard single storey (project-style, standard finishes): $2,800–$3,500/m²
- Standard double storey: $3,200–$4,200/m²
- Custom architecturally designed (single or double): $4,000–$5,500/m²
- High-end/luxury (premium finishes, complex geometry): $5,500–$6,500+/m²
These rates include everything from slab to practical completion: structure, roofing, cladding, internal linings, kitchen, bathrooms, flooring, painting, electrical, plumbing, and landscaping allowance.
They do not include land, demolition (if KDR), design fees, or council contributions.
They do not include land, demolition (if KDR), design fees, or council contributions.
Real Examples from Our Projects
Our Bulli Custom Home involved a challenging steep block with bushfire requirements. Our Woonona Custom Home was a more straightforward build on an easier site. The cost difference between projects like these comes down to site complexity and finish level.
Builds on steep, constrained sites with premium features (raked ceilings, cantilevered balconies, large glazing spans) push into the $4,500–$5,500/m² range. Straightforward designs on flat blocks with standard finishes typically sit in the $3,200–$3,800/m² range.
The difference? Complexity. Raked ceilings, large unsupported spans, steep sites, and non-standard materials all push costs up.
Builds on steep, constrained sites with premium features (raked ceilings, cantilevered balconies, large glazing spans) push into the $4,500–$5,500/m² range. Straightforward designs on flat blocks with standard finishes typically sit in the $3,200–$3,800/m² range.
The difference? Complexity. Raked ceilings, large unsupported spans, steep sites, and non-standard materials all push costs up.
Where Budgets Actually Blow Out
After 50 years of building custom homes, here is where we see people go over budget:
1. Site costs they did not expect
Sloping blocks, rock, reactive clay, or poor drainage can add $30,000–$80,000 to your foundation costs. In the Illawarra, the escarpment suburbs (Balgownie, Mount Pleasant, Keiraville, Mount Ousley) almost always have challenging soil. A geotechnical report ($2,000–$4,000) before you commit to a design saves you from nasty surprises.
2. Design changes after contract
Every change during construction costs more than the same change during design. A wall moved on paper costs nothing. A wall moved on site costs thousands. Finalise your design before you sign.
3. Allowances that are too low
Some builders set unrealistically low allowances for kitchens, bathrooms, and flooring to win the contract. When you go to select your finishes, you discover the allowance covers laminate, not the stone you assumed. We set realistic allowances from day one and show you exactly what each level of finish looks like.
4. External works
Driveways, retaining walls, fencing, landscaping, and pools are often excluded from the building contract. Budget 10–15% of your build cost for external works.
Full Cost Breakdown (Typical 250m² Custom Home)
Category | Estimated Range (AUD) |
Design + engineering + surveys | $30,000–$60,000 |
Council fees + contributions | $15,000–$40,000 |
Site preparation + excavation | $20,000–$80,000 |
Construction (at $3,500–$4,500/m²) | $875,000–$1,125,000 |
External works (driveway, landscaping, fencing) | $50,000–$120,000 |
Contingency (10%) | $90,000–$140,000 |
Total (excluding land) | $1,080,000–$1,565,000 |
This assumes a mid-to-high specification on a moderately challenging Illawarra site. A flat block with standard finishes will be lower. A steep site with premium everything will be higher.
How to Keep Costs Under Control
- Get a geotechnical report before you design. Knowing your soil type lets us design the right foundation first time.
- Lock in your design before you sign a contract. Changes cost exponentially more during construction.
- Understand what is included and excluded. Ask for a full scope of works, not just a per-square-metre rate.
- Set realistic allowances. Visit showrooms early so you know what things actually cost.
- Use a fixed-price contract. We quote a fixed price so your budget does not move unless you change the scope.
Is It Worth Building Custom?
A project home (volume builder, standard designs) in the Illawarra currently costs $2,200–$2,800/m². A custom home costs $3,000–$6,500+/m². The premium is real.
But you get a home designed for your specific block, your specific lifestyle, and your specific views. You get to choose every material. You get a builder who answers your calls (not a call centre). And in 10 years, your custom home will be worth more because it was designed with intention, not pulled from a catalogue.
If you are serious about building, book a consultation with Duane. We will discuss your brief, your block, and your budget, and tell you honestly what is achievable.
But you get a home designed for your specific block, your specific lifestyle, and your specific views. You get to choose every material. You get a builder who answers your calls (not a call centre). And in 10 years, your custom home will be worth more because it was designed with intention, not pulled from a catalogue.
If you are serious about building, book a consultation with Duane. We will discuss your brief, your block, and your budget, and tell you honestly what is achievable.