What is a granny flat, and why are so many homeowners in Australia choosing to build one? These self-contained secondary dwellings provide a versatile and cost-effective way to create additional living space. They are commonly used for rental income, multi-generational living, or increasing property value, making them a practical investment.
With the demand for granny flats in Australia growing, understanding their dimensions, costs, benefits, and legal requirements is essential. This guide covers everything you need to know to determine if a granny flat is the right choice for your property.
What Is a Granny Flat?
A granny flat is a self-contained secondary dwelling located on the same property as the main residence. It includes essential facilities such as a bedroom, bathroom, kitchen, and living area, making it suitable for independent living.
Originally, granny flats in Australia were designed for elderly family members, providing them with privacy while staying close to loved ones. However, their use has expanded, and they are now used as rental properties, guest accommodations, or even home offices.
A granny flat must meet local council regulations, including size restrictions and land zoning requirements. Unlike a house with a granny flat for sale, which comes ready-built, constructing one on your property requires proper approvals and planning.
What Makes It a Granny Flat?
For a dwelling to qualify as a granny flat, it must be:
- A self-contained unit with a kitchen, bathroom, bedroom, and living space.
- Located on the same lot as the main house, without separate ownership.
- Limited in size, typically not exceeding 60 square metres in most Australian states.
Granny flats are sometimes referred to as granny apartments, secondary dwellings, or accessory dwelling units (ADUs). Despite different names, the concept remains the same.
What Rooms Are in a Granny Flat?
A standard granny flat typically includes the following rooms:
- Bedroom(s) – Most granny flats have one or two bedrooms, depending on space.
- Kitchen – A functional area with cooking appliances and storage.
- Bathroom – A toilet, shower, and vanity unit.
- Living Area – A lounge or sitting space.
- Laundry – Some granny flats include a dedicated laundry or a combined bathroom-laundry space.
What is a granny flat compared to an attached or detached living space? Attached granny flats share a wall with the main house, while detached layouts are standalone structures. The choice depends on privacy needs and available land space.
How Do Granny Flats Compare to Other Living Spaces?
Granny flats are a popular choice for additional living space, but how do they compare to other small housing options? While they share similarities with secondary dwellings, tiny houses, and outdoor studios, each has distinct differences in purpose, legal status, and functionality. Below is a detailed comparison to help homeowners understand how granny flats stand out.
Granny Flats vs. Secondary Dwellings
A granny flat is a type of secondary dwelling, but not all secondary dwellings are legally considered granny flats. The key difference lies in their intended use, self-sufficiency, and council regulations.
- Granny Flats – Fully self-contained secondary dwellings that must include a bedroom, kitchen, bathroom, and living area. They are regulated under granny flat-specific council laws and cannot be separately sold from the main house.
- Other Secondary Dwellings – Includes converted garages, basement apartments, or loft spaces. These may provide living space but often lack full facilities like a separate entrance, kitchen, or bathroom. Some councils do not classify them as legal granny flats unless they meet strict self-containment criteria.
A house with a granny flat for sale is typically more valuable than a property with unfinished secondary dwellings because a fully approved granny flat is legally recognised and can be rented out.
Granny Flats vs. Tiny Houses
Both granny flats and tiny houses are compact housing options designed for independent living. However, they differ significantly in construction, mobility, and legal classification.
- Granny Flats – Permanent, fixed structures built on a foundation and subject to building regulations and council approval. They require a minimum land size (usually 450 sqm or more) and must meet zoning requirements before construction begins.
- Tiny Houses – Often built on wheels, making them portable and movable. While they offer flexibility, they are not permanent dwellings and may not require council approval. Some councils classify them as caravans, meaning they cannot be legally occupied as a full-time residence without special permissions.
A granny flat in Australia is a better long-term investment because it adds property value and can be legally rented. Tiny houses, while appealing for off-grid living, may face restrictions in urban or suburban areas due to zoning laws.
Granny Flats vs. Outdoor Studios
Outdoor studios and granny flats share similarities in size, but they serve very different purposes.
- Granny Flats – Designed for full-time living, including all essential amenities such as a kitchen, bathroom, and bedroom. They are suitable for multi-generational living or rental income.
- Outdoor Studios – Used primarily as workspaces, creative studios, guest rooms, or hobby areas. They lack full facilities, such as a kitchen or bathroom, making them unsuitable for long-term independent living.
An attached granny flat may share similarities with an outdoor studio, but its legal classification and intended use set it apart. If homeowners plan to rent the space or accommodate family members, a granny flat is the better option. However, if the goal is to create a home office or occasional guest room, an outdoor studio may be sufficient.
The Benefits of Adding a Granny Flat to Your Property
A granny flat is a smart investment that offers financial and lifestyle benefits.
- Rental Income – Renting out a granny flat provides a steady income stream, whether for long-term tenants or short-term stays.
- Multi-Generational Living – Ideal for elderly parents or adult children, offering independent yet close living arrangements.
- Increased Property Value – A house with a granny flat for sale is more attractive to buyers, boosting resale potential.
- Flexible Use – Can serve as a home office, guest house, or personal retreat.
With granny flats in Australia growing in popularity, they provide versatile housing solutions while enhancing property value and earning potential.
4 Key Considerations When Building a Granny Flat
Building a granny flat requires careful planning to ensure it is functional, private, and council-approved. Key factors to consider include accessibility, parking, privacy, and landscaping.
1. Access
A separate entrance improves privacy for both the main house and granny flat occupants, especially for rentals. Councils may require dedicated entryways, and tenants prefer direct street access rather than passing through the main property. If that’s not possible, a marked pathway can provide privacy.
For elderly residents, accessibility features like ramps, handrails, and wide doorways are essential. Soundproofing—such as insulated walls and double-glazed windows—reduces noise, making attached granny flats more comfortable. A secure, well-lit entrance with smart locks enhances safety, particularly for those living alone.
2. Parking
Many councils require at least one dedicated parking space for granny flats, particularly in high-density areas. Checking local zoning laws ensures compliance.
For small properties, solutions like shared driveways, tandem parking, or designated spots work well. If the granny flat is a long-term rental, having private parking makes it more attractive to tenants. Where possible, adding visitor parking, a carport, or a garage increases property value and convenience.
3. Privacy
Positioning the granny flat at the rear or side of the property improves privacy. For attached granny flats, insulated walls and double-glazed windows help reduce noise transfer.
Fencing and landscaping—such as tall hedges or privacy screens—create a physical barrier between the main home and granny flat. Ensuring windows do not directly face each other increases privacy for both dwellings. Outdoor spaces, like patios or gardens, should also have clear separation for added comfort.
4. Landscaping
Good landscaping improves both functionality and aesthetics. Even in small spaces, vertical gardens, potted plants, and outdoor seating enhance appeal.
For larger properties, defining separate garden areas for the main house and granny flat maintains privacy. Pathways, decorative lighting, and private seating create a welcoming environment. For rentals, low-maintenance options like native plants or artificial grass reduce upkeep. Motion-sensor lighting along pathways also improves security.
A well-maintained outdoor space not only enhances the granny flat’s appeal but also increases rental and resale value.
How Much Does It Cost to Build a Granny Flat?
The cost of granny flats when it comes to building depends on size, materials, and design.
- Basic 1-bedroom granny flat: $80,000 – $120,000
- Custom-built or larger granny flats: $150,000+
Buy Granny Flat vs. Building One
If you need a quick solution, purchasing a house with a granny flat for sale may be easier. However, building a granny flat allows for customisation to meet specific needs and preferences.
With granny flats in Australia increasing in demand, both options offer long-term value, whether for rental income or personal use.
Getting Approval for a Granny Flat in Australia
Before building a granny flat, homeowners must obtain council approval to ensure the structure complies with local regulations.
General Requirements:
- Minimum Land Size – Most councils require at least 450 square metres.
- Maximum Floor Area – Typically 60 square metres, though some states may allow larger sizes.
- Zoning Compliance – The property must be in a residential zone where granny flats are permitted.
Each local council has specific rules, including setback requirements, height restrictions, and utility connections. Some councils also have restrictions on renting granny flats to non-family members.
Applying for approval usually involves submitting building plans, site assessments, and permit applications. Homeowners should check state-specific regulations to avoid delays or costly modifications.
Frequently Asked Questions About Granny Flats
1. What is a granny flat in Australia?
A granny flat is a self-contained secondary dwelling built on the same property as the main house. It includes essential living facilities and is commonly used for family accommodation or rental purposes.
2. What makes it a granny flat?
A structure qualifies as a granny flat if it is self-contained, located on the same property as the main house, and meets local size regulations.
3. What rooms are in a granny flat?
Standard granny flats include a bedroom, bathroom, kitchen, living area, and sometimes a laundry.
4. What is the new name for a granny flat?
Granny flats are also called secondary dwellings, accessory dwelling units (ADUs), or granny apartments.
5. How much does it cost to build a granny flat in Australia?
Costs range from $80,000 to $150,000+, depending on size, design, and materials.
6. Can I rent out my granny flat in Australia?
Yes, many councils allow granny flats to be rented out, but regulations vary.
7. Do I need council approval to build a granny flat?
Yes, most states require approval, with rules on land size, zoning, and dwelling size.
8. Can a granny flat have two storeys?
Some councils allow two-storey granny flats, provided they meet height and design regulations.
9. Are granny flats a good investment?
Yes, they provide rental income, increase property value, and offer flexible living options.
10. Can I buy a house with a granny flat?
Yes, properties with existing granny flats are available for sale and are popular among investors.
Is a Granny Flat Right for You?
What is a granny flat? It’s a valuable addition to any property, offering rental income, increased value, and independent living space. With the rising demand for granny flats in Australia, now is the ideal time to invest in one.
For a modern and efficient solution, Portalux offers high-quality modular homes that can function as granny flats. Their prefabricated, energy-efficient designs include fully equipped kitchens and bathrooms, ensuring comfort and convenience. With quick installation and minimal site preparation, Portalux modular homes provide a stress-free alternative to traditional construction.
Contact Portalux today and explore what a modular house can do for you just like what a granny flat can do for your property.