Duplexes

1300 650 495

Visit Our Showroom 2/22 Hudson Avenue, Castle Hill, NSW 2154

Granny Flat Builder Sydney

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Popular Duplex Designs

If designing your own duplex is not an option for you, you can select from our best selling layouts below. These layouts can also be modified to further suit your property and personal requirements.

View by Design
View by Floor Plan

Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
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Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more

Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design 2

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more
Duplex Design 4

Our granny flats boost a modern, contemporary look for, 2 bedrooms with built in wardrobes and a shared bathroom and laundry. The modern kitchen is open plan features lots of storage space and well-sized living room area. Our design have the option of an alfresco area which is perfect for entertaining friends and family. View […]
- 0 Bed
- 0 Bath
- 0 Car
View more

Custom Built Duplexes in Sydney

At Inhouse Granny Flats, we understand that every person is different. We know that a set design may not be to your liking. Unlike other companies, we allow every client the opportunity to specifically design their own layout. Every block is different. Why should you settle on a layout that wasn’t designed for you? Liaising with our onsite duplex designer, each customer will be able to create their own floor plan, including room sizes and change of location. That way your duplex will be one of a kind.

the process

1. Getting a Quote

The first step to building a granny flat is an enquiry. When you call or email us, we will send you a free information pack so you get a better understanding of what we do. From there, our qualified builder will inspect your backyard free of charge to check the area and discuss your needs and requirements. Our sales representative will then send you a fee proposal, which outlines the necessary requirements for your granny flat as well as its inclusions and overall price.
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2. Flats and drawing stage

Once you have accepted the terms and conditions of our fee proposal, provided us with a 10.7 planning certificate (formally known as 149 Certificate) from council, a sewer diagram and you have paid a deposit, we will organise for a surveyor to carry out a site survey on your property.
Once we have received your survey our qualified Inhouse design team will then draw up a concept floor plan and organise a personalised meeting to sit down with you to ensure your needs are met and any design alterations are made.
Once you are happy, we will proceed to start your approval with a private certifier or via council.
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3. Contracts

Once your completed approval has been issued by a Private Certifier or Council, we will ask you to sign a Fair Trading Home Building Contract and organise your Home Owner’s Warranty. We will invite you in for a meeting to select all the materials and colours for your granny flat from our wide range of selections available in our showroom.
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4. Construction

We will schedule your project to start and order all materials you have selected for the build.
We will then be on-site organising earthworks, excavation and piering to prepare for the slab.
You will be appointed a site foreman who will guide and update you throughout the construction until the handover is complete.
At Inhouse, we know that this investment is important to you and we do our best to finish construction as soon as possible while not compromising the quality of your building. Your brand new granny flat will be completed within 12 -14 weeks.
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