What is a House Behind a House? Backyard Houses Explained

Many homeowners have a reasonably sized backyard. People opt for larger properties, so they have room for pets, children or throwing the occasional BBQ. But for some, that larger piece of land may sit there, unused. That’s why more and more Australians are utilising that space and investing in building a second house behind their homes. 

A house behind a house (HBH) is known by many names; the most common are the Rear Strata Development or a Battle-axe Development
. Smaller ‘house behind house’ dwellings may be considered granny flats or secondary dwellings.

But there’s more to houses behind a house than just building on a rear lot. That’s why we have gone ahead and outlined everything you’ll need to know about building your first HBH.

What Do You Call A House Behind A House?

A house behind a house is also called a Rear Strata Block, Battleaxe Block or Rear Strata Development. 

Unlike street-facing residential-style homes, there are quite a few more requirements before an HBH can be built within your property. There’s a lot of reasons why people decide to have a rear strata development within their block, the most common reasons are;

  • Renting out the rear strata development while staying in their current home.
  • Sell the original property to reduce mortgage and move into the rear strata development.
  • Sell both properties for higher profits.


Most people tend to overlook the benefit of having a rear strata development built rather than new freestanding property. First is the reduced investment risk. As a homeowner, you already own the lot where the new property will be built upon. The other advantage is the peace of mind that comes with going through the construction and development process from the comfort of your home.

Subdividing your block and building a new home is a generally more streamlined process for sourcing finances and going through council approvals. This is also considered one of the best ways to get into the real estate/ property development business.

A rear strata block is an excellent financial investment. Many people decide to build on a battleaxe block or rear strata so they can generate income with much less risk than buying and building on a new property. You can use your property to build a house that you can rent or sell to have some passive income coming in while you continue to work or enjoy retirement.

Many Australians also look to rear strata blocks to functionally use as housing. Some people use it as temporary accommodation while your main home is being renovated while others have it for temporary or permanent accommodation for family members. 

What Is A Small House Behind A House Called?

Smaller houses behind an existing home – or backyard houses – may be granny flats or secondary dwellings, though they can also be rear strata or battleaxe block developments. 

That terminology is used by people within the building and real-estate industries. A small house in the backyard is more commonly known as a granny flat or guest house.

A battleaxe block is simply the rear part of a subdivided block. These dwellings may be accessed through a narrow road or driveway on one side of the property, creating the inverted L-shaped “battleaxe” it’s named after.

Although generally interchangeable, the terms ‘rear strata’ and ‘battleaxe’ actually have a slight difference in the context of HBHs. Unlike a battleaxe development, rear strata developments do not require the narrow access road/ driveway at the side. Instead, other access points may be provided for the rear property that does not necessarily create the inverted L-shaped driveway. 

Can I Build A House Behind My House?

It’s possible to build a house behind your house if your lot is big enough. You will have to meet council requirements for lot size and boundary setback, among other requirements, to receive planning permission for a secondary dwelling.

It could be a small studio, an office, or even a compact one-to-two bedroom dwelling. In some cases, homeowners opt to build a duplex or even a triplex on a small lot. However, keep in mind that a larger property is needed to facilitate building a second house. 

The most common reasons why people opt to construct another house within their block are; additional accommodation, increase in living space, and rental income.

Individuals planning to have a house or development built behind their home should keep in mind local council planning regulations and requirements, as these differ when it comes to building on a rear lot. 

To learn more about requirements for rear strata developments, see our guide to building on a battleaxe block.

Determining If Your Property Allows For A House Behind A House (HBH) 

Each Australian state and council has specific rules and regulations regarding building a house behind a house. It’s always best to check with local councils about the process in your area. However, a general checklist to follow is:

  1. Identify if your block has development potential, check your area of residence’s residential design codes. In Perth, these are referred to as R-codes
  2. Identify the feasibility of your block. Many factors need to be taken into consideration to check your block’s feasibility. The most critical are the minimum driveway distance between the existing home and the fence, local council policy, and the available space in the backyard.
  3. Confirm the external costs. Take into account infrastructure requirements and their costs. Engineering, water corporation, electrical, gas, and National Broadband Network (NBN) are some of these requirements.

What Is A Battleaxe House?

A battleaxe House or development is a type of HBH in which the access point is through a narrow driveway to the side of the block. This creates an inverted L-shape that resembles a battleaxe. Battleaxe house designs result from the subdivision of a block of land either by the owner of the original standing house or by property developers.

What Is A Secondary Dwelling?

A secondary dwelling, also known as a granny flat, is a type of self-contained accommodation. It can be found within, attached to, or separate from an individual home.

What Is The Difference Between Dual Occupancy And  Secondary Dwelling?

The most obvious difference is that a secondary dwelling is a smaller home that is secondary in terms of size and location relative to the main home. On the other hand, a dual occupancy house does not have a primary home and are each considered the main dwelling.

Aside from this, some specific characteristics differentiate the two types of properties such as:

  • The limits to the size of the dwellings.
  • The number of households allowed for each kind. 
  • The street addresses.
  • The number of car parking spaces.
  • The nature of leasing and the subdivision, among others.

What Is Urban Infill?

Urban Infill is a new development located on vacant or underdeveloped land within an existing community surrounded or enclosed by other types of building development. The term is commonly used to refer to single-family houses built in existing neighbourhoods, but it may also refer to new commercial, office, or mixed-use areas.

Urban infilling brings with it some benefits for the neighbourhood and surrounding communities;

  • It removes the aesthetic and safety concerns associated with underdeveloped or vacant property.
  • It allows involved communities to achieve and sustain the population density required to attract amenities such as parks or community services.
  • It may be effective in increasing the supply of more affordable homes.

What Are The Benefits Of Higher Density Housing?

There have been debates about the advantages and disadvantages of high-density housing. 

Wherever you stand in the debate, higher density housing inevitably come with advantages, such as:

  1. It reduces the carbon footprint of individuals since apartment living saves more space and is a very energy-efficient way of living.
  2. It’s much more affordable and may help address issues facing society such as homelessness and affordability of housing for young people in low/ minimum wage jobs and families with single parents.
  3. Areas/ communities with higher density tend to receive improvements regarding the amenities of the area. This could come in the form of more restaurants, gyms, or services. In turn, this helps generate more revenue for local businesses within the community.
  4. High-density housing can improve transport options within and around the communities. This may also result in a significant increase in the walkability of the neighborhood.

Share This Post

Share on facebook
Share on linkedin
Share on twitter
Share on email

More To Explore