Perth, Western Australia

Granny Flat Prices in Perth

6 services from $5,000

Granny Flat Prices in Perth

Prices include GST. Allow 12–20 weeks for a standard granny flat build from approval to handover. Site conditions, council requirements, and finishes affect final costs.

Filter by price range$5,000 – $275,000
$5,000$275,000
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Granny flat prices in Perth

Granny Flat Tips for Perth

Western Australia's "ancillary dwelling" rules allow granny flats on lots over 450m² in most residential zones — Classic Granny Flats is a well-known local builder

Perth's sandy soils generally make for easier and cheaper slab construction compared to clay sites in eastern states

Perth granny flat build costs are moderate compared to Sydney — expect 5–10% less for equivalent specifications

WA requires a building permit for all granny flats — the process typically takes 4–8 weeks through your local council

Popular Options at a Glance — Perth

1-Bed Granny Flat

$106,000

avg · $78,000$135,000

Complete 40m² build with kitchen & bathroom

2-Bed Granny Flat

$156,000

avg · $118,000$195,000

Full 60m² build with 2 bedrooms

Kit/Prefab (1-bed)

$70,000

avg · $48,000$92,000

Factory-built kit delivered & assembled

Granny flat prices in Perth start from $5,000/job. A 1-bedroom granny flat costs $106,000 on average. Prices include GST. Allow 12–20 weeks for a standard granny flat build from approval to handover. Site conditions, council requirements, and finishes affect final costs.

The best granny flat type depends on your budget, lot size, and intended use. Kit/prefab options in Perth start from $48,000 for a 1-bedroom. For rental income, a 1-bedroom or 2-bedroom with standard finishes offers the best return on investment. For family use, consider accessibility features and a more generous layout.

A standard granny flat in Perth takes 12–20 weeks from slab to handover. A 2-bedroom build averages $156,000 and takes 16–20 weeks. Kit/prefab builds can be completed in 8–12 weeks. Council approval adds 2–24 weeks depending on the pathway.

Yes — all granny flats in Perth require building or planning approval. Your builder or certifier will advise on whether you can use a fast-track approval pathway or need a full development application. The approval process, costs, and timeline vary by council area.