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How Much Does a Granny Flat Cost in Western Australia?

A granny flat in WA typically costs between $120,000 and $300,000 depending on size, finish level and site conditions.

A compact studio or one-bedroom up to 40 sqm generally starts around $120,000 to $150,000. A two-bedroom flat between 50 and 70 sqm, the most common size in WA, typically ranges from $150,000 to $250,000. High-end finishes, sloped sites or regional locations can push costs higher.

On top of construction, budget around $10,000 for design, council approval (DA) and building permit (BP) documentation.

Use our cost estimator above to get an indicative range based on your specific project: size, finish level, site conditions and location across Western Australia.

Arcaia Studio prepares council-ready granny flat documentation for homeowners and builders across all of WA, including Perth, Busselton, Dunsborough, Margaret River, Geraldton and Exmouth. Fixed pricing, delivered typically within 14 days.

Granny Flat in Yallingup Currently under construction in Yallingup, Western Australia.
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