National guide · Australia
How much does a granny flat cost in Australia?
A granny flat (or secondary dwelling) can add family space or rental income - but prices range widely by type and site. Here's the national 2026 picture, the costs that catch people out, and where to find builders near you.
Granny flat cost by type
Kit / prefab studio (~30m²)
Factory-built, delivered and installed. Fastest and most affordable path.
1-bedroom built on site (~45m²)
Site-built with a proper kitchen and bathroom. More design flexibility.
2-bedroom secondary dwelling (~60m²+)
Larger footprint, often for rental income or multi-generational living.
National 2026 ranges, build only. Approvals, siteworks and service connections are usually extra.
What drives the price
- Site access and slope - a crane or difficult access adds thousands
- Connecting water, sewer and power to the main dwelling
- Council approval pathway and whether it can be rented separately
- Finish level, inclusions and whether it needs its own driveway or parking
Whether a granny flat can be rented out separately - and what approval it needs - is set by your state and council. Check the local pages below before you commit.
Local costs & builders
Get a real quote and local rules.
BuildPilot is live in South Australia and Victoria and expanding across Australia. Open your state for local granny flat costs, the approval pathway and experienced builders.
Building in Australia
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