As the demand for smaller self-contained homes grows, so too do the types of people wanting to move into them. With this in mind, here is a selection of some of the best granny flat ideas.

Also referred to as secondary residences, granny flats have experienced a massive surge in popularity in recent years, though these days they are just as likely to house complete strangers as grandparents or other close relatives.

granny flat backyard

The original granny flat concept was all about providing independence to older relatives, without breaking up the family unit altogether; and ensuring you could keep an eye on those family members who needed such assistance.

Granny flats have a long history. They date back to the Dowager houses of the Victorian period. These were smaller houses on large estates across England, Wales, and Scotland, into which widows would move after the death of their husbands (the formers owners of the estates). At this time, the heir to the estate (normally a son) would move with his family into the main residence.


Why the recent granny flat boom?

There are several advantages of building a granny flat. Apart from the already mentioned original motive of keeping loved ones close at hand, it allows you to add a new residence to your property without actually sub-dividing. This can provide a source of rental income (including the tax advances this brings). Those choosing to rent granny flats include everyone from students to young professionals, older couples, and everyone in between who doesn’t require a larger house.

Adding a granny flat can also increase the value of the overall property. Caution needs to be taken, however. There are negatives. The amount by which a granny flat will boost your house value is not uniform across the country. Indeed, in some cases it is almost negligible. Also, once the granny flat is built, you are no longer free to subdivide your block. In addition, not everybody likes the prospect of living so close (as little as 3m) away from neighbours.


What are the rules/regulations around building a granny flat?

In Australia, granny flat construction regulations vary from state to state. In recent years, regulations have become more free.

NSW - In NSW, granny flats must be at least 60m2 in size. They may only be built on blocks of at least 450m². Sydney has the largest number of granny flat ideas in the country.

ACT - In the ACT, granny flats must be at least 90m2 in size.

Tasmania - In Tasmania, granny flats must be at least 60m2 in size.

Western Australia - In WA, the dimensions of granny flats must be between 60m2 and 70m2. New laws mean that it is possible to lease them to non-family members.

Queensland - In Brisbane and across Queensland, the dimensions of granny flats must range between 60m2 and 80m2.

South Australia - In Adelaide and across South Australia, granny flat designs must have a size of between 60m2 and 70m2.

Victoria - Until recently, Victoria had extremely strict regulations that meant granny flats had to be movable and could only be occupied in house by relatives. However, The Victorian Government is currently running a trial planning code across four council areas (two regional councils and two in metropolitan Melbourne). Under the trial, the granny flat floor plans must measure under 60m2 and they must be under 5m in height. Also, anybody can live in them.


How much do granny flats cost to buy?

Depending on quality and size, granny flats can cost anywhere between $20,000 to more than $200,000 to build. At that lower level, there are flat-pack DIY granny houses. Meanwhile, $70,000 is how much you would need to buy and install a one-bedroom prefabricated granny flat. At the top end ($200,000), you can expect to buy a custom designed larger two bedroom granny flat or three bedroom granny flat.


Granny flat plans – granny flat designs

Here are eight of the best granny flat plans available across Australia.

manor 31 exterior

manor 31 plan

1. ‘Manor 31’ granny flat

Available from Granny Flat Solutions, this functional little 3 bedroom granny flat features a full bathroom with laundry space. You can buy it with your choice of floor covering.


clubhouse exterior

clubhouse floor plan

2. ‘Clubhouse’ granny flat

Boasting an attractive L-shaped layout, this granny flat from Ranbuild comes with a double skillion roof for a modern aesthetic. In addition, it comes with plenty of room to add a deck for entertaining. It is available from Backyard Shacks.


sea spray exterior

sea spray plan

3. ‘Sea Spray’ granny flat

Measuring just 9.9m x 4.7m, with a 46m² floorplan, the one bedroom, one bathroom Seaspray granny flat is simple, clean, sturdy, and most importantly affordable. It is now available form Imagine Kit Homes.


silverdale exterior

4. The ‘Silverdale’ granny flat

Backyard Grannys’ Silverdale granny flat features an impressive double skillion roof. At 60m² it is surprisingly spacious. Apart from its two bedrooms, the Silverdale features a beautiful living area with a raked ceiling, as well as highlight windows.


abbotsbury exterior

abbotsbury plan

5. ‘Abbotsbury’ granny flat

Available from Rescon Granny Flats, the ‘Abbotsbury’ is a sturdy 2 bedroom dwelling with a 60m² floorplan. One of the best 2 bedroom granny flat floor plans, its highlights include built-in wardrobes and highly liveable open plan living/kitchen area. The Abbotsbury is also available in a ‘Designer Plus’ model that includes a covered front entry, an upgraded fa├žade, and upgraded windows. It is available from Rescon Granny Flats.



the mod house backyard

mod house plan

6. ‘The Mod House’

Though also available in larger versions, this one bedroom Mod House from Prebuilt may be configured to suit all sorts of locations, including rural locations, beach side locations, or dense urban settings. It features spacious open plan living zones, extensive full-height glazing, flexible plan options and high-quality internal inclusions. This is surely one of the best 1 bedroom granny flat floor plans.


samford valley exterior

samford valley side view

samford valley house plan

7. Samford Valley Small House

Located 21km outside of Brisbane in the Samford valley and with a granny flat floor plan of just 80 sqm, this granny flat boasts large decks that seem to be at odds with its compact size. Making the most of its sub-tropical South-Eastern Queensland location, its decks can be used as an extra living space for most of the year. A two-bedroom house, it is based on a design from Baahouse + Baastudio called Lincoln 2B.


waratah granny flat plan

8. ‘Waratah’ Granny flat

Available from Granny Flats Australia, as this granny flat floor plan shows, the Waratah features two multi-purpose bedrooms which can easily serve as study, spare room, gym, or art studio, depending on preference.