Granny Flat Approvals…State by State Guide for success in 2025

Just starting out on the Granny Flat journey ?

The granny fat approval process need not be complex. First of all it’s best to identify if your local area council allows granny flats to be built. Most states of Australia allow a 2nd dwelling (granny flat) in some size or dimension and configuration. Differing rules & regulations apply across Australia on a “State by State” basis.

For countries outside of Australia check with your local Council or State body.

What is a Granny flat or Secondary Dwelling ?

A granny flat, or secondary dwelling, is defined as self-contained accommodation within, attached or separate to an individual home.

Most older existing homesites in Australia allow for permission to build a secondary dwelling (granny flat), with the appropriate complying approvals.

2 bedroom accessible series design pictured by designacube

There are three basic types of granny flats:-

1. A ‘conversion’ is a granny flat that is built in your existing home. If you have an unused bedroom and bathroom, for example, you might be able to convert the space into a granny flat.

2. An ‘extension’ is a granny flat that is attached to your home.

3. A ‘detached ‘granny flat is a separate dwelling on your property.

A council or accredited private certifier can certify granny flats as complying developments without the need for a Local Council development application, provided they meet specific standards in the relevant State Planning policies.

Building Approvals

Regulations vary in different states and relevant Council areas, but in general:-

Dependent on your property attributes and it’s State and /or location, you may have two options – via a Development Application (DA) or Complying Development Certificate (CDC).

Both approval pathways require a Council Certifier or a Private certifier to give you the final seal & tick of approval.

Regulations have changed a lot in recent years and vary wildly from state to state so please check with your Builder, Designer and / or Architect plus local Council to be fully abreast of what is required for your project.

What is Complying Development ?

Complying development is a combined planning and construction approval for straightforward developments that can be determined through a fast-track assessment by a council or an accredited private certifier.

Complying development applies to homes, businesses and industry and allows for a range of approvals of a new dwelling house including granny flats, alterations and additions to a house, new industrial buildings, demolition of a building, and changes to a business use.

How do I get a “fast tracked” building approval in NSW ?                              Approvals under the fast-track complying development pathway in NSW can be issued in as little as 20 days.

Granny Flat living area rendered image supplied by designacube

Exempt Development

Did you know that you can do some minor building works to your house, shop or business without a development application? This is called exempt development. This means that low impact works not requiring a full merit assessment by council can be done more quickly and with less cost…

more info on Exempt Development in NSW.

Granny flats as Complying Developments must be:-

• established in conjunction with another dwelling (the principal dwelling),
• on the same lot of land as the principal dwelling (and not an individual lot in a strata plan or community title scheme), and
• may be within, attached to, or separate from the principal dwelling.

The Approval Process for secondary dwellings

The approval process varies on a “State by State” basis. Each state has a set of planning laws to follow but by and large all state governments support the addition of secondary dwellings on existing house lots.

We’ve broken the approval process down for you in basic terms on a “state by state” basis below.

Australian State by State Approval Process

Each Australian State has varying rules for granny flat approval. We have listed each state below with information relating to specific conditions of approval for the relevant State.

We hope this helsp you navigate the at times complicated process of gaining approval for you granny flat.. Once approved the race is then on to get your granny flat built. Once approved you may be looking for a Builder of your granny flat ?

Granny flat approval requirements for New South Wales

To lodge an application for a granny flat in NSW as a complying development, you will need to complete your nominated accredited certifier or councils’ approved Complying Development Certificate (CDC) application form.

Using this approval pathway, the granny flat may be approved within 20 days. If the granny flat does not meet the requirements for complying development, a full development application will need to be lodged with the relevant council.

You will find more information on the NSW State Govt Planning Portal

NSW Requirements for Complying Development

the basics :-

• must be zoned residential
• one secondary dwelling per block
• minimum Lot Size of 450m2
• 12 metre width at the building line of the existing dwelling
• maximum size of granny flat – 60m2 (excluding decks)
• attached or detached (also on top of existing garage)
• side setbacks – 0.9m; rear setback 3.0m
• 3m from existing trees over 4m in height
• can’t be subdivided or strata titled

2 bedroom extended deck model pictured by designacube

Granny Flat approval requirements for Queensland

Granny Flat approvals process in QLD varies from Council to Council jurisdictions.

A certifier must approve any work for granny flats before you start construction in Brisbane City QLD. This is separate to a planning approval.

Granny flat approval requirements for Brisbane QLD

Brisbane City Plan refers to an extension to an existing dwelling house in a residential zone for a granny flat as a ‘secondary dwelling’. It can be a maximum of 80 square metres in size.

A granny flat for a member of your household does not need Council approval. This is as long as you meet the accepted development, subject to requirements criteria in the Dwelling house code or Dwelling house (small lot) code.

In QLD you will need to lodge a development application if :-

• the granny flat is bigger than 80 square metres in size b.) it is more than 20 metres from the main house.
• you will need a development application for dual occupancy if you are renting it to someone who does not form part of your household.

QLD Requirements for Complying Development

the basics :-

• must be zoned residential
• minimum Lot size of 450m2
• maximum size of granny flat 80m2 (excluding decks)
• attached or detached

Victoria

VIC Requirements for Complying Development

the basics :-

Victoria is unlike any other state in terms of granny flat planning laws. Granny Flats in Victoria cannot be rented out. Only family members are allowed to use them. Tough planning requirements restrict the Victorian granny flat market.

In Victoria, the answer to why ? could have more implications than anywhere else in the country. The state has some of the toughest regulations on granny flats – and meeting the conditions can be time-consuming and expensive. (above link from RACV).

Council laws vary, but typically the occupant must be a dependant, and the building must be removed once they die or move out.

Victorians – information is available on your local council’s website. You can also visit Council chambers and talk to a planner or your local Building Consulting expert, architect and/or designer, builder or industry expert to seek advice.

Important Update for Victorian rules

As part of the Allan Labor Government’s bold planning reforms, it will soon be easier for Victorians to build a small second home on their property – giving families a space to grow together and boosting housing supply.

From next month, families will no longer require a planning permit to build a small second home on their property.

Too often, families want to keep their older and younger generations closer together – but are priced out of established areas around the state.

This change will make it easier for families to build a small second home on their own lot – near jobs, public transport, education and healthcare services, as well as existing social connections. For more information go to States react To Housing Affordability Crisis…new rules for Granny Flats

Granny flat approval requirements for Australian Capital Territory

A granny flat, known as a “secondary residence” in the ACT, can be anywhere from 40 m2 to 90 m2. Minimum land size of 500 m2 and must be zoned residential. It must be a water sensitive urban design and suit the needs of people with disabilities. It can be rented out, but you must provide private open space for tenants plus one car parking space.

ACT Requirements for Complying Development

the basics :-

• must be zoned residential
• minimum Lot size of 500 m2.
• minimum Granny Flat size .40 m2
• maximum size of Granny Flat 90 m2
• minimum one car parking space, cannot be in the ‘front zone’.
• clear, unobstructed pedestrian access
• only the primary residence owner can own the granny flat
• reasonable levels of privacy for adjoining residential blocks, including solar access to their dwellings.
• compliant with setbacks.

Compliant with the Australian Standard AS 4299 Adaptable Housing (Class C).         that is, “easily adaptable to suit the needs of people with disabilities“.

Urban series Studio model pictured by designacube

Granny flat approval requirements for South Australia

When building a granny flat in South Australia, you must abide by regulations set by the SA Government and your local Council. Otherwise, you may not gain approval for your development.

A granny flat is also called a “Dependant Accommodation” in SA. You must gain Development Approval from your local Council, ensuring it meets the requirements of their Development Plan.

Most Councils’ will give approval, under the provision that an immediate family member will occupy the granny flat. Meaning, they cannot be an investment.

As such, the unit must be connected to the same services (i.e. electricity, phone line, sewer and water) as your main home.

SA Requirements for Complying Development :-

the basics :-

• property must be a minimum of 600sqm.
• floor size must be a maximum of 60sqm or 70% of the total floor area of the main home (whichever is less).
• maximum of one separate bedroom and
• must provide at least 20sqm private open space
• a granny flat is also called ‘Dependant Accommodation’ by the SA Government. That means it is generally used for accommodation by a dependent relative – i.e. grandparent/s or a teenager.
• to be classified as “Dependant Accommodation”, the unit itself is required to be dependent on the primary dwelling for services.
• in SA this means your granny flat must be connected to the same services as the primary dwelling, such as:-
• Electricity
• Telephone line
• Sewerage / waste control system
• Water connection
• Driveway

There are generally 2 types of Consent required for Development Approval for a granny flat in South Australia:-

Development Plan Consent & Building Rules Consent

Each SA Council has its’ own Development Plan, a copy of which you can get from your local SA Council or at www.planning.sa.gov.au).

Construction approval in SA can be obtained by either a Private Certifier or Council certifier.

Important Update for South Australian rules

New SA planning rules ensuring ‘granny flats’ can be rented to anyone and refining criteria to fast-track approvals for new homes in master-planned areas are now in effect,

Amended regulations now ensure all existing ancillary accommodation (granny flats) can be leased or rented out, potentially bringing hundreds of new homes to the rental market.

These changes mean it is no longer an offence to enter into an agreement to rent a granny flat with anyone, even if development approval limits use or restricts occupation to family of the main home’s residents.

This important change has been made given the housing accessibility and affordability issues within the State. For more information go to States react To Housing Affordability Crisis…new rules for Granny Flats.

Western Australia

Granny Flat approval process in WA is not dissimilar to NSW

You must have a minimum property size of 450sqm (unless your local Council states differently). The maximum floor area your granny flat is allowed is 70sqm. Although this may differ across local Councils up to 100sqm.

It is possible to rent out your granny flat to non-family members, but approval from your local Council is typically required first.

Granny flat approval requirements for Western Australia

the basics : –

• must be zoned residential
• one secondary dwelling per block
• minimum Lot Size of 450m2
• maximum size of granny flat – 70m2 although some Councils will allow up to 100m2
• can’t be subdivided or strata titled

one bedroom coastal series model pictured by designacube

Granny flat approval requirements for Tasmania

Granny Flat rules in Tasmania define the maximum size to be no more than 60sqm and or 30% of the total area of the main dwelling (whichever is less).

Granny Flats in the land of the “Big Apple” can be rented to anyone. There is no obvious rule regarding a minimum block size. In fact there is actually no state-wide policy on what you can and can’t do, so the rules will vary between local Councils themselves.

Please Note: above information is a guide only. Please consult with your local Planning Consultant, Architect and or Designer, Builder or Local Council when deciding or checking on the process for approval and construction of your granny flat.

Owner Builder Advice

Whilst being an Owner/Builder can be a satisfying experience it can also be a nightmarish journey. If you’re not 100% confident or have an anxious type personality and don’t connect well with people then maybe owner / builder isn’t for you ?

Co-ordinating and supervising trades can be a challenging and exhausting business. A building project is not a simple task for a novice. The best trades people also generally like to work with Builders who are in consistent control of the co-ordination of the build and provide regular on-going work.

For example you don’t want the plasterer arriving on site after travelling two hours to get to site to find out the electrical & plumbing ‘rough-ins’ haven’t been completed.

There are a myriad of reasons why its not always a great idea to “do it yourself” including maintaining your sanity and peace of mind knowing that the work has been completed by a professional.

You wouldn’t let your Builder extract your teeth or perform surgery on your family members, so consider carefully before jumping in as an owner builder.

Often overlooked as well but extremely important is if you are in a relationship. Building can be very stressful, especially if you are a “first timer”. You don’t want to be a successful owner/builder but also separated or divorced in the process !

There are distinct advantages of utilizing the services of licenced professional Builders and or Project Managers. Owner Builders can make the mistake of not considering the “actual cost” of their own time and labour.

The three most important elements of Project management are Time, Cost & Quality. If any one of these three elements lack then your project cost can ‘blow out’ substantially.

Professional input at every stage of the design & build process is critical for a successful project. Professionals do add exceptional value and advice throughout the process plus add dollars in capital value, so think carefully before deciding whether to be an owner builder.

The Australian Housing industry in general is top of the class in business when it comes to efficiency in both delivery and cost.

Housing Industry professionals are usually found as members of the Housing Industry Association (HIA) or as members of the Master Builders Association in your state.

one bedroom urban series model pictured by designacube

Conclusion

Gaining approval for a granny flat project can be an easy process if you know where to look. The complying development approval process is the easiest and less stressful path. Approval under a Complying development can be gained within 10-20 days if all information is ready at hand to present to the Private Certifier.

If you are required to go down the path of a “full blown” Development Approval (DA) process, be prepared for lengthy delays with your Local Council. DA’s can be triggered by such things as flood prone land, bushfire zones, environmental issues ie.) rare species of native fauna, high traffic location issues etc.

Every DA also requires a “Statement of Environmental Effects” (SEE) which can only be prepared by a professional consultant such as a Town Planner…. very costly as multiple reports from various consultants wil be required.

So, before rushing in to gain approval, do your home work carefully before committing. Thank you for visiting grannyflatnews.