If you have ever considered purchasing a demolish and build property, or looked at developing a block of land, you might have seen the term residential design codes (R-codes). Every block of land in WA is assigned an R-Code, which determines how many dwellings can be built on that piece of land.
The higher the R-Code number, the more properties it can support.
What are R-Codes?
Officially, Residential Design Codes, or R-Codes, provide planning and design provisions for residential development across Western Australia.
R20
An R20 code indicates a low-density residential area, with the minimum site area per dwelling set at 350m2, with an average site dwelling of 450m2. This means that for a 900m2 block, a developer could build two dwellings.
R25
An R25 zoning requires a minimum site area of 300m2 per dwelling, with an average of 350m2 per dwelling. This allows for a smaller square footage of homes, but does not allow for more dwellings on our example block of 900m2.
R30
The minimum site area for each dwelling under an R30 code is 260m2, and the average site area is 300m2 per dwelling. This means three dwellings could be built on a 900m2 lot.
R40
In an area with R40 zoning, the minimum site area is 180m2 and the average site area is 220m2 per dwelling. As an example, four dwellings could be built on an 880m2 lot. The maximum building height for multiple dwellings is two storeys.
R50
For R50 zones, the minimum site area is 160m2 and the average site area is 180m2 per dwelling. In this instance, four dwellings could be built on a 720m2 lot. The maximum building height for multiple dwellings is three storeys.
R60
When it comes to developing dwellings, the minimum site area is 120m2 and the average site area is 150m2 per dwelling. This means approximately six dwellings could be developed on a 1000m2 lot. The maximum building height for multiple dwellings in R60 is three storeys.
Where can I find the R-codes for Western Australia?
You can find the R-codes for WA on a number of websites. The most reliable source for R-codes in Western Australia is the Western Australian government’s website under the Department of Planning, Lands and Heritage.
Most local council websites will also have copies of the WA residential design codes for ease of reference. You can also call them to ask about the zoning for a specific block of land.
Why are R Codes important?
R Codes are really important because they provide a framework for the residential development of an area. Not only do building codes for residential homes set standards for dwelling space, they are also important in ensuring that local resources are adequately planned to provide for residents.
They are also designed to encourage a diversity of housing types and a socio economic mix, allowing for a plethora of residential developments, including single, grouped and special-purpose dwellings.
As Western Australia continues to experience a housing shortage, the state government has revised the R-codes to support more affordable housing. This has resulted in many areas now being assigned higher R-codes, allowing developers to build more dwellings on the land there.
Do you need an R-code to subdivide?
Each piece of land should be assigned an R-code. It’s not that you need an R-code to subdivide. It’s that each block has an R-code, and you must adhere to it when you decide to subdivide.
The R-code dictates the minimum lot size allowed on that block. This size will determine how you subdivide it and how many dwellings you can achieve there.
What are the most common R-codes?
How common an R-code is usually depends on where in Western Australia it is. Higher R-Codes, such as R60 and above, usually denote high-density areas, likely to be found in inner-city location. These R-codes support high-density developments like apartments.
Further away from the city, into the outer suburbs, an R-code such as R20 allows for larger lot sizes and fewer dwellings. Typically, this indicates a lower-density area, where land and space are not so hotly contested.
It’s worth noting that some long-term residents in established suburbs object to the rezoning of their suburbs to allow for more dwellings. Working with an experienced developer who understands an area’s demographic and history can help to manage these relations as you begin a build.
Changes to R-Codes
Changes to the R-Codes in 2024 have seen a reduction in the average and minimum lot sizes of some R-Codes. Lots with a minimum site area of 350sqm are now permissible under the R20 code, 300sqm under the R25 code and 260 sqm under the R30 code.
It is worth noting that although minimum lot sizes have been reduced under several codes, in some instances the average lot sizes have stayed the same. This amendment allows for an increased flexibility in lot design, rather than additional dwellings.
Another important change is the amendment which allows granny flats to be constructed on a lot for occupation by a non-family member. This opened up new flexibility and additional income streams.
What do recent changes mean for me
Recent changes to the R-Codes should be seen as a good thing, because they reflect the government’s understanding of the challenges faced by developers. They also provide greater opportunities to increase housing density, which means individual blocks of land can be more profitable.
The update to the codes is also intended to reduce red tape, which should make property developing a smoother process.
It is, of course, vital for developers and homeowners to ensure they understand the changes and that they adhere to the new codes.
Other factors to consider when developing
While it’s essential for property developers to understand building codes for residential designs, there are also other factors to consider when deciding how to develop a block.
Overshadowing
It’s important that developers consider and mitigate against the possibility of overshadowing when planning the dwellings on their block. Overshadowing occurs when a house blocks the sunlight from entering its neighbour’s living spaces, and it can be caused by the height of a home, as well as its placement, fencing or trees.
Utilities
A block can look like a very attractive prospect on the surface but you also need to consider what is under the land. Underground utilities can be difficult to reach, particularly if you are looking to subdivide, and there may be extra costs to make sure you connect these services to additional dwellings on the block.
Don’t forget to take these complications, and costs, into account.
Access
When determining how many dwellings you plan to situate on a block, you need to make sure that each dwelling has ready access. Parking and separate driveways are also considerations that will make the properties significantly more attractive when the time comes to sell or rent them out.
How Novus Projects can help
We provide comprehensive building services, including land subdivision and the creation of new titles, offering a one-stop solution for all your design, construction, and development needs.
Over many years of developing projects, we have accumulated a vast amount of knowledge on how to overcome challenges and continually strive to make sure the project works for everyone, every time.
Using our knowledge of subdividing properties and building developments, we can help our clients avoid the potential pitfalls of property development. Contact us today to discuss your next project and see how we can help.