How do I know if I can build a duplex on my land?

Before you consider building a duplex on your existing land or buy land to build a duplex you need to do your homework to fully understand where you can and cannot build.

Not so long ago, the regulations varied a great deal from Council to Council but in 2018 a new code was introduced by the NSW Government that makes it easier to understand the requirement to build a duplex, and provide uniform rules for the entire state.

It is also possible to have land rezoned but this can be a protracted and costly exercise so ideally, you’ll buy an existing block where a duplex is already allowed. Either way, ZAC Homes assists clients with permits and rezoning applications to make it easier for you. We understand all the regulations and can guide you through the process.

What is a duplex?

In simple terms, a duplex construction is two homes built on the same block of land that share a common wall. The two dwellings can either share one land title and owner, or can be subdivided into separate titles so they can be owned and sold separately.

Building a duplex on your current land can be an excellent investment or a great multi-generation home, but there are several things to consider before deciding whether it’s a great option for you and your family.

What are the land requirements to build a duplex in NSW?

On 1 July 2020, the NSW Government renamed its existing Low Rise Medium Density Housing Code to the Low Rise Housing Diversity Code (LRHDC) to reflect the diverse housing choices it provides. The Code applies to all local government areas in NSW.

The LRHDC allows dual occupancies to be approved through the fast-tracked Complying Development process.

The Code applies to properties zoned R1, R2, R3 and RU5 across NSW, where this type of housing is already permitted under a council’s Local Environmental Plan (LEP).

Under the code, blocks must be either 400 square metres or the minimum lot size required by the council, whichever is greater. As well, blocks need to be a minimum of 15 metres wide, or 12 metres wide where the required car parking is provided at the rear or accessed by a secondary road.

For a duplex, the dwellings must be located side-by-side and each dwelling must have a frontage to a public road. No dwelling can be located behind another dwelling on the same lot except on a corner or a parallel road where each dwelling fronts a different road.

Dwellings must be no higher than 8.5 metres and no more than two storeys.

There are also several setback requirements for both primary and secondary roads, and adjoining properties. The minimum side setback is 0.9 metres.

The code requires each dwelling to be a minimum of five metres wide and off-street parking must also be provided for at least one car per dwelling.

Can my land be rezoned for a duplex?

The first step is to consult your local council. Councils produce detailed strategic plans, showing what areas and suburbs are set to be rezoned so check that first.

If that doesn’t apply to your situation then generally if you want to build, extend, subdivide or change the use of your land you will need to lodge a development application (DA) with the local council.

Keep in mind that rezoning a property can be a difficult and costly process. There are public hearings and there are no guarantees that your DA application will be approved.

The NSW Government is currently reviewing the process and aims to make it easier and quicker to apply for rezoning with the new rules coming into play by 2023.

The reforms aim to cut the time it takes to process a proposal to change planning rules by a third and establish an appeals pathway for planning proposals to overcome delays and progress rezonings that are consistent with strategic plans.

Can I subdivide my duplex?

As mentioned previously, a duplex can be either two homes that share one land title and owner or can be subdivided into separate titles so they can be owned and sold separately.

It can be subdivided in certain circumstances and in particular local government areas with certain zoning. Factors like the lot size and width, privacy between the two dwellings, and some environmental constraints like stormwater drainage, are taken into consideration.

As well there are floor area limitations like floor space ratios, and parking rules governing how many parking spaces are provided.

How can ZAC Homes assist with zoning for my duplex?

When building a Duplex with ZAC, everything is taken care of. We have facilitated over 300 duplex builds and are experts in size, position and house style. We can advise on the best way to get the most value out of your investment and your block.

We take care of everything from design, approvals, demolition (if required) and construction. 

ZAC Homes builds with trust, respect, integrity and pride, which we work hard to deliver to every client. Call us on 1300 350 793 or send us an online enquiry and our team will work with you to design and build your dream home.

Want more information?

Contact our team using the form or using the details below

Phone: 1300 350 793


Address: Unit 6, 119 Coreen Avenue, Penrith, 2750

Book an appointment online or visit us at our display homes at Box Hill and Marsden Park

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