That’s not a Granny Flat… It’s a minihome

We are passionate about making your tailored ideas a reality. This means we’re flexible, transparent and direct with our communication, working with you around the clock, and following up your every need.

We will ensure that your build is hassle free with seamless delivery.

Let us help you with building:

  • Your dream Home
  • Your high yielding investment property
  • Extra room for loved ones

Unbeatable Quality Assurance

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First in the Industry

Granny Flats Australia is Australia’s original Granny Flat builder operating since 2009

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We are the Builder

Yes! We are builders and handle everything from start to finish, even council!

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100% Satisfaction

Over 50% of our annual builds are repeat or referral builds

Our Display Homes

Walk through a real Granny Flat

At the Granny Flats Australia display centre you can walk through two of our most popular designs. We have on show two 60m², 2bedroom designs. The spacious ‘Banksia’ design with standard inclusions and our open plan, fully upgraded, luxury ‘Belmont’. While you’re here you can view our wide range of materials, colours and upgrade options, pick up some design ideas and speak with our granny flat specialists.


Saturdays Closed
Weekdays 9am-4:30pm


8/10 Anella Ave,
Castle Hill NSW 2154

Over 50 floor plan designs to choose from or customise your own

Browse through our extensive range of floor plans for 1, 2 and 3 bedroom designs. You’ll find our standard 2 bedroom granny flat plans and other more complex designs with two bathrooms, garages, carports, alfresco areas and patios. Our plans come in all different shapes and sizes and you’ll certainly find something to fit your needs.

Customer Testimonials

Nearly 5 yrs ago we had a Granny Flat from Granny Flat Australia(GFA) built for my mother in law. We did our homework before selecting GFA which included speaking to others who had also used GFA. GFA were and are still a pleasure to deal with, all their tradesmen were of a high standard and very pleasant to deal with.

Jim B

I’m a home buyer/investor - we've just finished our 4th granny flat, a 60ms, 2 bed, brick, 15ms alfresco, + single garage in North Sydney. From the initial project planning and help with interior design, to the execution it has been a fault free experience - coming in on time and on budget. They did a superb job on time and the quality of their work was excellent as always. I was also pleased with the follow up and after care – the entire team are easy to work with, they are very good at project management.

Alexanda G

Cid & the team built us a fantastic house after we suffered a horrible experience using another granny flat company at our previous address. My husband was referred to you by another Grannyflat company who couldn’t handle the complexity of our build and we are so glad we were. You all helped us tremendously during the decision making process as well as the design and planning phases. It was so hard to envision, but the build turned out spectacular, better than we ever envisioned...we love the design, layout, and quality of construction.

Beki L

“Helen and I can’t express to you all enough how happy and amazed we are with the beautiful Granny Flat you have built us. We distinctly recall getting serval quotes and seeing several sample flats and we believed GFA seemed the most professional. We knew Granny Flats Australia was the team to trust with our new home.”

Ben & Helen

I’m not one to usually leave feedback but I am making the effort to share my experience with everyone hoping it somehow helps you just like they helped me, after having lived in the same house in Baulkham Hills for nearly 20 years, it was time to make some changes and build a granny flat. After I did extensive research, I found Granny Flats Australia and I contacted them, told them about my situation and couldn’t be happier that I did. From day one, their involvement was great.

Christopher S

Hi everyone - an excellent review from us because it's well deserved. My experience has been terrific, I've sent you a feedback email but I thought it would be nice to post it as well for others to read. After reading all your other reviews below it seems everyone has the same great feedback and experience I've had. Your entire staff is so personable, I didn't think the experience would be so easy but well I haven't had to do a single thing, I thought I'd have to do so much more, so easy from my end, just sat back and your team did it all, all I did was pay haha seriously!!

Bree L

"I would like to start off by thanking the team for their professionalism along the journey of the granny design and construction. The team is committed with strong customer focus. In the present moment, I’m considering Granny Flats Australia for my next project. Hands down, if anyone was to ask for a great team who will work for you to achieve any desired granny flat solution, there is no hesitation to mention the team I dealt with."

Tony – St Andrews

I and my wife are strongly impressed with your company thus far, you came highly recommended above the rest from our dear friend in the construction industry and based on the comparison of the gentleman who conducted the quote to all the 4 companies who attended our home we can now clearly understand why they held your company with such high regard, the information, attention to detail, preparation and professionalism given to myself and my wife in our own home was incomparable.

Maneesh D

Guys honestly thank you so very much for everything, your honesty and integrity is what we need more of in this industry. We paid for quality and we got it, we are now living in our granny flat and renting out the main house, it was a dream run with you, this is a thank you from me and my whole family, i wish you would please also build our new house, if you change your mind we'd love for you and you only to build it for us. i look forward to another future build with your company, until then take care and thank you so much again. (Phillipe & Family)

Phillipe G

Please accept this email as a word of appreciation for prompt and excellent service provided by your contractors and the staff at your office. We will highly recommend my families and friends to contact you for any building of granny flats they have in mind.

Yash & Mamita – Erskine Park

They were always upfront and honest. The whole team is extremely professional and genuine. Good communication throughout the job. The quality of construction, materials, and appliances was great! Polite professional trades. The contractors are fast, nice and professional.

Michael S

Thank you so much. It has been a pleasure to have your team build our Granny flat. It’s been the smoothest project we have ever undertaken. Keep up the good work. Please pass on a huge thank you to the entire team. Would highly recommend you guys.

Anthony – Narellan Vale

I visited your showroom in Castle hill on the wk-end & i feel it's important i leave a review, the Belmont is gorgeous, it's like i walked into a brand new home just smaller, the finishes are divine. Your staff were really personable & the overall vibe i got from your company was beautiful.

Angie P

"Everything flowed beautifully from the first visit to the showroom where I was given undivided attention. Cid helped me come up with the development idea that would work on my block. At no time did I feel pressured to sign up to anything other than what I wanted – a 50 square metre granny flat even though a 60 square metre flat could have worked as well. Sandra’s advice with material selection was invaluable and it all looks fantastic."


Your Dream Granny Flat Is Closer Than You Think

  • Get your keys in 6 months guaranteed
  • Customise your design in 3D with us
  • Easy to get started – we handle it all from design to approval to construction
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