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How big can a granny flat be in NSW?

The Granny Flat Experts build many granny flats across NSW for many clients. Finding out what size granny flat can be built is probably the first question we are asked. With so many variables to this answer, we have put together important information regarding this very topic.

Granny Flat size guidelines and build information. Granny flats are usually smaller than regular houses, but still offer the same amount of living space. 

How big can a granny flat be?

When considering building a granny flat, it is important to keep in mind the size restrictions that apply in your area. In most cases, the maximum size for a granny flat will be determined by the amount of land that you have available. Generally speaking, granny flats need to be at least 15 square meters if they are going to be used as living quarters. 


Some local councils also have regulations regarding the number of bedrooms or bathrooms in a granny flat, so it is important to check with your city or town hall before committing to a design. Here is the secondary dwelling information to check out from the NSW government website. It has some very interesting Frequently asked questions too.

Ultimately, however, the size and layout of your granny flat will depend on your own needs and preferences – whether you are looking for extra space for an elderly relative or just want another place to entertain guests. So go ahead and explore all of your options, and find the right solution for your unique circumstances!

Whether you're looking for a cozy little hideaway or roomy living quarters for family members, you should be able to find a granny flat that meets your needs. So if you're thinking of downsizing or simply need more space for your loved ones, consider investing in a granny flat 

designs for granny flats

What is the average size of a granny flat

The first factor is the size of your property. The Australian Government's National Planning Policy Framework states that granny flats should not take up more than 40% of the total area of the land on which your house is located. So, if your house is located on a 500 square metre block of land, your granny flat should not be larger than 200 square metres. This is the maximum size allowed by law.

The second factor to consider is local council zoning regulations. These regulations vary from council to council, so it's important to check with your local council before you start construction on your granny flat. Some councils have special rules in place for granny flats, so it's best to be informed before you begin any building work.

Typically the average size of a granny flat will always depend on the main residence and the block size.

Can you build a secondary dwelling on a block less than 450m2?

The area of your lot is the only factor that determines if you can have compliant development. If it's less than 450 square meters, then no matter how many bedrooms or bathrooms are in this secondary dwelling--it won't be considered complying with building codes and will therefore not meet accessibility standards for people with disabilities!

What is the approval process?  5 Steps

granny flat approval certificate.jpg
  1. Obtain approval for all works (Development Application or Complying Development Certificate)

  2. Construct granny flat

  3. Obtain Occupation Certificate (OC) for granny flat

  4. Construct the main house

  5. Obtain final Occupation Certificate for all works – within 5 years of first OC

Firstly, a Development Application (DA) for both the primary and secondary dwelling can be lodged and approved by the council or a Complying Development Certificate (CDC) issued by a private certifier (or council) for all works involved.

Best designs to suit your needs!

Granny flat planning procedures

It all starts with a query. The easiest part of any granny flat development or build is to talk to someone that knows best. It's no good to assume things before you talk to the experts in the industry. 

George Elias from The granny flat experts is ready to take your call and discuss your ideas with you. 

How big can a granny flat be?

View Our Projects

Different sized granny flats

Dual - Series 1

small 2 bedroom granny flat floor plan
larger 2 bedroom granny flat floor plan
very large granny flat floor plan
Granny Flat Floor Plan design-Dual - Series 4
tiny 2 bed granny flat
Lerge living area floor plan
Granny Flat size design
Granny Flat L-shaped design
double story granny flat

Dual - Series 2

Dual - Series 3

Dual - Series 4

Dual - Series 5

Dual - Series 6

Dual - Series 7

Dual - Series 8

Dual - Series 9


How big can a granny flat be in NSW? - Granny Flat Experts - Sydney

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