Do I Need Council Approval Before I Build a Granny Flat?

So, you’ve decided that you would like to add a granny flat to your property. Great decision!

Granny flats, also known as secondary dwellings, can benefit tenants and property owners in numerous ways. But there is much more to a granny flat build than most people realise. First things first, you need to figure out whether you need council approval before building.

The need for council approval when building a granny flat will depend on two things.

  1. Your main property and block of land.
  2. Where you live.

In Australia, the laws that regulate the building of granny flats differ between states. Often within a state the rules will also be different for each local council. For the majority cases you will need approval from the council before starting to build your granny flat. In some cases, where certain requirements have been met,  a full development application is not needed. This said, it is a good idea to always involve the local council to ensure that you are truly meeting these requirements.

The council rules for granny flats can be very confusing and for this reason many people choose to engage the help of a professional. Despite being quite different across the states and often local councils within a state, the granny flat laws are all in place for the same underlying reason: to prevent renters or granny flat dwellers from being subject to unsafe living conditions. Let’s review some of the granny flat rules that apply in each state!

The Granny flat approval process is different in each state

New South Wales

The state of NSW is relatively open minded when it comes to granny flat approvals. There are two types of developments: a complying development and a non complying development.

If your granny flat plans meet the complying development requirements, you can let out a big sigh of relief, as you won’t need to submit a full development application. Complying developments are usually approved within 20 days. If your granny flat plans turn out to be non complying. Your chance of building lies in the hands of your development application, which will need to be lodged with your local council.

Once your flat is approved, you should also have the option of renting it out. Which is not always the case for the other states.

The rules for complying granny flats in NSW are outlined in the State Environmental Planning Policy (Affordable Rental Housing) 2009.  There may be some variation between the exact specifications of local councils. A brief summary below:

  • Property must be located in a specified residential zone.
  • Land must be at least 450sqm.
  • Granny flat size maximum: 60sqm.
  • Additional parking space must be available.
  • No plans for a basement or addition to existing basement.
  • No plans for a roof terrace on the topmost roof of a building or additions to existing roof terrace.
  • No sub division of land.


In Victoria, granny flat approval laws are very specific to the local council. If you move just an hour away, if is safe to say that the rules that applied to you previously will be slightly different for your new property. So, when it comes to getting approval for your granny flat in Victoria, hurry on over to your local council and get acquainted with the laws that apply.  There are quite a few things that can impact your application, including the following, as stated on the City of Whitehorse website:

  • Existence of planning overlays.
  • Size and location of the land.
  • Title restrictions, easements, covenants or agreements.
  • Impact on surrounding neighbours.
  • Whether the proposal meets the objectives of other relevant Council policies.

What about if you just want to build something simple for a family member?

In many areas of Victoria, the easiest and also often the only way to build a granny flat, is to build a Dependent Persons Unit or a DPU. It is described as a moveable building used only for housing a dependent member of the existing household.

For some councils, you won’t need a permit to build a Dependent Persons Unit. However, if you don’t stick to the rules exactly, it could easily become an illegal dwelling. In some cases it is necessary to inform the council of the person who will be living there, and when they leave, it must be removed. Which isn’t very practical.


In Queensland the rules, yet again, are very much tied to your local council. In many cases, if you are planning to house family members in the dwelling you don’t need to submit a full development application. However, you do need to make sure that the dwelling does meet some other requirements before proceeding.  Actually understanding these requirements can be very hard for someone not in the industry so it is best to consult to professional. More details on the requirements from the Brisbane council can be found here.

The Brisbane city council notes three things that indicate certainty of a development application requirement for your granny flat.

  • The granny flat is larger than 80 sqm.
  • The granny flat is more than 20 metres from the main property.
  • You intend to rent to someone outside of your household.

Unfortunately some councils in queensland don’t allow you to build a granny flat with the intention of renting to external parties – even if you submit a full development application. If you intend to use your granny for rental income at any point in the future it is always best to talk to the local council. You may find out once you sell the property that the new owners don’t see the value in a granny flat that can’t be used to generate extra income.

South Australia

Let’s move down even further south, to South Australia. Rest assured the rules for granny flats are different here yet again. Granny flats in this state are not able to be rented to third parties, even those armed with a full development application and approval.

And why are South Australian granny flat laws so tough? You will have to speak to your local council members for that answer!

If you do decide to build a granny flat for members of your household, you will still need to get it approved by your local council. Some requirements outlined on the City of Mitcham website are as follows:

  • Your land occupies at least 600 sqm.
  • The land is not split into more than one title.
  • The granny flat cannot exceed 60sqm.
  • Private open space of at least 100sqm to be shared by both residences.
  • Additional car parking space for granny flat occupant
  • The granny flat is similar in architectural style and general appearance to the main dwelling.


Western Australia

When it comes to granny flat laws Western Australia is certainly keeping up with their easternmost neighbours in NSW. The rules were relaxed on the west coast in 2013, in response to a sharp rise in the cost of housing.

As outlined by the City of Waneroo website, you don’t always need a planning permit for a granny flat, but you always need a building permit. Rural properties generally need planning approval for granny flats. Some common rules are as below, but remember, they do vary for each local council.

  • Land must be at least 450sqm.
  • Granny flat cannot exceed 70sqm.
  • There must be an additional parking space.

If your property in Western Australia includes an approved granny flat, you can rent it out to whoever you like; family, friends or tenants who don’t form part of your household.

Australian Capital Territory

The ACT boasts the largest square metre allowance for a granny flat in the country; your granny flat can be up to 90 sqm. Like in NSW, a development application is not required when certain conditions are met. As always, they do vary between localities.

There is no distinction made between a granny flat you would use for members of your family or one that you intend to rent out and derive income from.

Despite not requiring development approval, building approval is always required. This is mostly the case, no matter which state you live in.


In Tasmania, you won’t have to submit a development application if your plans comply with the local council laws. These requirements can be pretty extensive, so best to consult an expert and get them in writing. Extras such as flood risk and also heritage requirements make compliance more difficult. The Glenorchy city council outlines some general rules on their website. We have briefly summarised some of the points below:

  • Minimum lot size for general residential: 450sqm.
  • Minimum lot size for inner residential min lot size: 200sqm.
  • Minimum lot size for low density residential: 1000 sqm.
  • Private open space of 24 sqm.
  • Sunlight: must have at least one habitable room (other than a bedroom) that faces between 30 degrees west of north and 30 degrees east of north.
  • Privacy: limit overlooking into private open space or habitable rooms by ensuring adequate separation and screening of windows, decks and balconies.
  • Car parking provision and access.

Northern Territory

2014 was the year that made building a granny flat in the Northern Territory much simpler. The regulations were eased, making it a faster process,  It also gave residents the ability to rent out their granny flat to external parties, if so desired.

In the Northern Territory, residents often don’t require council approval to build a granny flat. However, it still does need to meet all the required conditions. Even though you might not need council approval, to build a granny flat you will need to either employ a NT registered building certifier or seek a building approval before you start.  

It is also advisable to consult your local council in regards to the specific laws that govern your property. Below some common council conditions that you may need to fulfil for your granny flat build.

  • The floor area of the granny flat can’t exceed 50 sqm for residential properties or 80 sqm for those in rural areas.
  • There is no specified land size, this should be confirmed with the local council.
  • Standard building height and dimension requirements.
  • An extra car space for the granny flat resident.

Related Questions

How much does Granny flat approval cost ?

The cost for approval will vary according to your situation. For example if your land is already in a state that meets the requirements it will be much lower. Using the online calculator on this granny flat approvals website, came to a total of $8,000. It could also reach as high as $15,000.

How many granny flats can I have?

You are permitted just one granny flat on your block of land. There is to be one main residence and one extra dwelling only. This rule is consistent across each state of Australia.  

Can a granny flat be attached to a house ?

Yes, your granny flat can be attached to the main residence. Depending on various factors, this type of granny flat build is normally more expensive than if it was to be detached.  A free standing granny flat also generally offers more privacy to tenants. Make sure to check with your local council.

So now you know, building a granny flat is not as simple as just making the decision to go ahead! It some areas it can be quite a long and costly process just to get approval, in others it is much faster. It all comes down to where you live, and the site that you wish to build on. Just remember, it is important to consult your local council for the rules that apply to you and to follow through with building approval before going ahead. Cutting corners may land you in a situation where your granny flat is deemed illegal. And that is not a situation you want to be in.

Leave a Comment