The number everyone wants up front
For an early house-size exercise, this guide uses an illustrative range of $3,000 to $4,000 per square metre, before land and site-specific work. Use the calculations to compare sizes, then ask the team for current pricing against your design and section. These planning figures are not a priced offer.
A rate per square metre cannot tell you which specification is included. Put the proposed cladding, glazing, kitchen, bathrooms, heating and finishes beside the number. Ask separately about external work, so a landscaping allowance is not confused with the house construction cost.
Illustrative budgets for different home sizes
Rates per square metre only mean something against the sizes families actually build:
- 145 m² three-bedroom starter: roughly $435,000 to $580,000
- 186 m² four-bedroom family home: roughly $560,000 to $745,000
- 224 m² five-bedroom with two living zones: roughly $670,000 to $900,000
The costs price guides leave out
Keep site work visible beside the house estimate: earthworks, retaining, ground information, engineering, approvals, service connections and the finished driveway. Confirm which landscaping and outside finishes are included in the proposal for your property.
Start with a free site evaluation to discuss the section and identify what needs investigating. Ask what information is required for the next pricing step, which items remain allowances and what sits outside the proposed set-price scope.
Run your own numbers
Our build-cost calculator does the per-square-metre maths for your size, finish and site type, and the mortgage calculator turns the total into a weekly figure. Both are free and neither asks for your email first.
Separate the headline figure into a project budget
Create rows for the house, the site, professional work, outside finishes and your own moving arrangements. Mark each figure as an estimate, allowance or quoted amount. Leave missing items visible rather than treating them as zero.
- Does the figure include land or just construction?
- Which site and external costs sit outside it?
- What information is needed for a written proposal?
Quick answers
Is it cheaper per square metre to build bigger?
Generally yes. Kitchens and bathrooms are the expensive rooms; simple extra floor area dilutes them, so a larger home usually costs less per square metre than a small one.
Do these rates include GST?
Ask for GST to be explicit in the written estimate or proposal, so you are comparing totals on the same basis. The calculations here are planning examples, not a contract figure.