Granny Flats rules in Perth
Building a granny flat in Perth? City of Perth applies the Western Australia planning framework. Here's what that means locally — plus the overlays worth checking on your specific block.
No planning approval if it meets the R-Codes
Yes. An ancillary dwelling of up to 70 m² that meets the R-Codes deemed-to-comply rules needs no planning approval - just a building permit - and there has been no minimum lot size since April 2024.
Key rules at a glance
| Maximum floor area | 70 m² (deemed-to-comply) |
| Minimum lot size | None (350 m² minimum removed April 2024) |
| Planning approval | Not required if deemed-to-comply |
| Setbacks | Per the local planning scheme |
| Can it be rented? | Yes - separately from the main house |
| Self-contained | Yes (own kitchen and bathroom) |
Heritage, flood and bushfire controls on your specific lot can remove the fast-track and require a full application — even when the general rules say you're fine.
Granny flats in Perth
City of Perth is the authority for Perth in Perth. The statewide Western Australia rules above set the baseline; the council can apply extra local controls, and heritage, flood or bushfire overlays on your lot can change what's allowed.
Frequently asked questions
Do I need council approval for a granny flat in Perth?
Often not. Western Australia allows a granny flat to proceed without a full development application when it meets the standards, and City of Perth follows that framework. But local overlays — heritage, flood or bushfire — can remove the fast-track, so check your exact address before you rely on it.
Which council approves a granny flat in Perth?
City of Perth is the consent authority for Perth (Perth). You can review local planning controls on the council website and lodge through your state planning portal.
Do I need planning approval for a granny flat in WA?
Not if it meets the deemed-to-comply rules of the R-Codes - up to 70 m² and the required setbacks - in which case only a building permit is needed.
Sources
- Ancillary dwelling (granny flat) information sheet - WA Planning ↗
- Revised R-Codes now in effect - WA Planning ↗
Related building rules
General guidance only — not professional planning advice. Local requirements in Perth can differ from the statewide summary and change over time; always confirm with City of Perth before starting work. Last reviewed: July 2026.
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