R-codes are used by developers to determine the number of dwellings that can be built on a parcel of land.

Local Planning Schemes, developed through local councils, will then apply a density coding to residential zoned land. The R-Codes apply to all properties and they not only determine lot sizes but important design elements such as:

  • Type of dwellings
  • Building height and size
  • Landscaping
  • Boundary set-backs
  • Parking
  • Privacy and much more

The current R-codes as they stand for single house(s) and grouped dwellings; and multiple dwellings in areas coded less than R40 are as shown in table 1.1.

Key items to note are the minimum and average lot sizes. The minimum size of the lot is the smallest size an individual lot can be. This area however cannot be applied to all lots, as developers still need to achieve the average lot size across the entire development. The minimum lot size is in place to help make use of awkwardly shaped lots while still providing a suitable space for a home.

Open space is, as the name suggests, space that isn’t occupied by a building. This includes open air pergolas and outdoor living areas, driveways and areas underneath the eaves.

Open space is not tied to any one building, but the development as a whole.

When designing developments, a portion of the open space requirement can be used to implement common driveways, gardens and visitor parking areas.

Table 1.1 R-codes

Putting the R-Codes into practice

To put this into perspective, consider the following example. Say we have purchased a plot of land that is zoned R40 and has a frontage of 20m and a length of 35m. This provides us with an area of 700m2.

With an R40 zoned property requiring an average lot size of 220m2, there is the potential to place three dwellings onto the property while still having room for amenities.

We must also consider that a development on an R40 lot will require a minimum of 45% of the area to be kept as open space. In this example we would need a total of 315m2 open space on the entire development, and the remaining 55% of the land area can be covered with buildings, otherwise known as the ‘site coverage’.

While this may seem straightforward enough, we need to consider accessibility to the rear lots. A simple solution here is to allow a 70m2 common driveway down the side of the property. This will become common property to the development and will also contribute 70m2 of open space for the lots it affects.

With 70m2 of open space being apportioned to the common driveway of lots one and two, those lots are left with an average of around 71m2 per lot to be used as open space.

As noted, part of this can be used by an outdoor area, such as a 20m2 Alfresco area. See example below. 

R-codes example

What influences the zoning R-Codes?

While most suburbs are zoned R20, areas with higher population density, such as those closer to major metropolitan hubs tend to have a higher zoning. In addition to existing zoning, councils may increase the zoning of an area if it is closer to public transport or shopping centres.

How do we find out the zoning and the size of a potential development property?

When looking for development properties, realtors will generally put the size of the lot in the listing. While this can provide developers with a fair estimate of the size, a more accurate figure can be found on the local council’s website. Each council will have their own online mapping service. By looking up the potential lot, the legal area, R zoning and any applicable town planning schemes are available.

What happens if I don’t have enough land to warrant a subdivision?

For current land owners or developers that would like to squeeze in an additional dwelling, but the property falls just short of achieving the average lot size there is still hope.

One option is to appeal to the planning commission. While the R Codes are fairly straightforward, there is the possibility of obtaining special approvals that allow for a 5% variance in the average lot size. This process can take some time however and does not always end with approval.

A second option involves purchasing land from a neighbouring property. This process is handled in the same way as any land sale, with the additional area being incorporated into the existing lot. It is important to note that this option can not be used to split the lot into individual green titled lots, but rather for built or survey strata developments.

These are not the only options available for developers to increase their opportunity for subdivision. For property owners looking to subdivide and get the most from their land, it’s always a good idea to get great advice. By working alongside a knowledgeable professional, your profits can be increased while considerably minimising your risks.

If you would like to learn more about maximising the potential of your property, or if you have any other development enquiries

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Disclaimer: Any advice contained in this article is of a general nature only and does not take into account the objectives, financial situation or needs of any particular person. Therefore, before making any decision, you should consider the appropriateness of the advice with regard to those matters. Information in this edition is correct as of the date of publication and is subject to change.