Do You Need Council Approval for a Granny Flat in WA? What Homeowners Should Know First
- Jun 23
- 4 min read
Planning a granny flat in Western Australia just became a lot more straightforward. Since April 2024, sweeping reforms to the state’s Residential Design Codes have removed the need for council planning approval for many homeowners looking to build an ancillary dwelling. But “no planning approval” does not mean you can build without any sign-off at all. There are still rules to follow, permits to obtain, and design decisions that will determine whether your project runs smoothly or stalls before a slab is poured. This guide breaks down exactly what the changes mean, what approvals you still need, and what to confirm before you get started.
What Changed in April 2024
In April 2024, the WA State Government’s revised Residential Design Codes (R-Codes Volume 1) came into effect, removing several barriers that had previously made building a granny flat slow and complicated. The WA Government described the reforms as nation-leading changes designed to cut unnecessary red tape and boost housing supply across the state. The table below summarises what shifted.
Requirement | Before April 2024 | From April 2024 |
Planning (council) approval | Required in most cases | Not required if R-Codes are met |
Minimum lot size | 350sqm | No minimum lot size |
Maximum floor area | 70sqm | 70sqm (unchanged) |
Grouped dwellings and strata lots | Not permitted | Now permitted |
Extra car bay | Required in most cases | Not required in most cases |
Design compatibility | Required to match main home | Currently under review |
Planning Approval vs Building Permit: Know the Difference
This is the point where most homeowners get tripped up, and the distinction is important.
A planning approval (also called a development approval or DA) is assessed and issued by your local council. It evaluates whether your proposed granny flat is appropriate for its location, zoning, and surrounding area. Under the new rules, a compliant granny flat no longer needs this.
A building permit, however, remains mandatory regardless of whether planning approval is needed. It confirms your structure will meet safety and construction standards under the Building Code of Australia. Building permits are processed by a registered private building surveyor or your local council’s building department and typically take around ten business days to issue.
The key takeaway: you likely will not need to deal with the council’s planning team, but you will still need a building permit before construction can begin.
When You Still Need Council Planning Approval
The planning approval exemption does not apply to every project. You will need to lodge a development application with your local council if:
Your granny flat exceeds 70sqm in internal floor area.
Your property does not meet the setback requirements in your local planning scheme.
Your property sits within a heritage overlay, special control area, or bushfire-prone zone.
Your local planning scheme includes provisions that override the standard R-Codes exemption.
If any of these conditions apply, speaking with a building designer experienced in council assistance processes before finalising your design is strongly recommended.
Key Requirements to Qualify for the Exemption
According to the official government info sheet on ancillary dwellings, your granny flat must satisfy the following to be exempt from planning approval:
Maximum internal floor area of 70sqm.
Located on residentially zoned land.
Setback requirements of the local planning scheme must be met.
Can be attached to, integrated with, or detached from the main dwelling.
Permitted on grouped dwelling and strata lots.
No additional car bay required in most locations, with exceptions in areas with limited public transport access.
Who Can Live in the Granny Flat?
Under the current rules, there are no restrictions on who occupies an ancillary dwelling. It can house an elderly parent, a teenager seeking independence, or a private tenant under a standard rental agreement. Renting the granny flat out is fully permitted, making it an increasingly popular option for homeowners who want to generate rental income while contributing to WA’s tight housing supply. Family status does not affect eligibility.
Design Matters as Much as Compliance
Satisfying approval criteria is only one part of building a successful granny flat. Thoughtful design is equally important. A well-considered ancillary accommodation design will make the most of the 70sqm limit, delivering two bedrooms, a bathroom, and open-plan living without feeling cramped. It will also integrate comfortably with your existing dwelling and site conditions. Design decisions made early are far cheaper to change than those discovered once construction has started. Engaging experienced building design specialists who understand both the R-Codes and your local council’s expectations reduces the risk of delays and costly redesigns.
Frequently Asked Questions
Do I need council approval to build a granny flat in WA?
For most homeowners, no. Since April 2024, compliant granny flats up to 70sqm on residentially zoned land are exempt from planning approval. A building permit is still required in all cases.
What is the maximum size for a granny flat without planning approval?
The maximum internal floor area is 70sqm. Anything larger will require a development approval from your local council before construction can begin.
Can I build a granny flat on a small block?
Yes. The previous minimum lot size of 350sqm was abolished in April 2024. You can now build on any size block, provided all setback and zoning requirements are satisfied.
Can I rent out my granny flat to someone who is not family?
Yes. Anyone can legally occupy an ancillary dwelling, including private tenants. Standard residential tenancy laws apply.
Does my granny flat need to match the style of my main home?
The previous requirement for colour, roof pitch, and material compatibility is currently being reviewed by the State Government. Confirm the current position with your local council or building designer before finalising your design.
Are building permit fees still payable if I don’t need planning approval?
Yes. Building permit fees are separate from planning fees and are still required. Fees vary by local government and are based on the estimated construction value of the project.
Start Your Granny Flat Journey with North Coast Design
At North Coast Design, we have been helping Perth and Mandurah homeowners design and document exceptional living spaces for over 20 years. Our team specialises in ancillary accommodation design and provides end-to-end support, from initial concept through to building permit documentation and council assistance. We work closely with clients throughout the process so nothing is left to chance. Ready to get started? Book a consultation with our team today and let us bring your granny flat to life.