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Dual Occupancies




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Dual Occupancy

A Dual Occupancy, also known traditionally as a Duplex, is fast becoming one of the most popular forms of construction across New South Wales and Australia. A dual occupancy gives you the ability to build two dwellings on one block of land and in most council’s you are able to subdivide into a smaller parcel of land than the usual minimum lot size.


At Duplex Building Design, we have built and developed our business to be a niche designer for investors, developers and builders. Due to the profit and potential that comes from dual occupancies, we work on these kind of projects week in week out.

Dual Occupancy Design Process

Project Feasibility Analysis

This is a phase that gets missed by many firms, a surgeon would not do surgery until first diagnosing what the problem is, this is the most important phase of any project. Here we carry out due diligence on the site, check all of the site constraints and council controls. Here we also check the area you are wanting to build in to ensure that you don’t over capitalise on the project. 

Concept Design & Design Development

Once we have studied all of the site constraints and controls and your project needs, we now have a very detailed brief to design a dual occupancy that meets all of your needs, is compliant with council controls and comes in within your budget. Because we are a niche duplex designer, we work on hundreds of dual occupancy projects each year, we know what work, we have a strong knowledge of design options and understand the need to maximise space, create natural light, solar passive design and cost saving measures. At this stage you will get some high level sketch floor plans and 3D Views with the option to make revisions as we go along.

Approval Documentation

Once the design is finalised, we then work closely with you to prepare all of the plans and documentation for approval. At this stage we will either do a development approval through your local council, or if the location and site allows we can get your dual occupancy approved as a complying development, which is a much faster and fast track approval process. As most of our clients are investors we understand time is important, the longer you hold the land the more interest you pay so fast approvals are key.

Key Questions About Dual Occupancies

What is the difference between a duplex and a dual occupancy?

In Australia they are the same thing, a duplex is an attached dual occupancy, meaning that you can have two (dual) occupants on one parcel of

Can you subdivide a Dual Occupancy?
Yes in most cases you can subdivide a dual occupancy, most council’s in NSW allow for a torrens title subdivision for dual occupancies. The great thing about a dual occupancy is that generally the minimum lot size for the dual occupancy is much less than the minimum lot size for a standard subdivision. The main difference here is that the subdivision of the dual occupancy can’t happen until after the dual occupancy is built.
What size block do I need for a Dual Occupancy?
Every council is different across NSW, the main key elements to look for are found in the Local Environment Plan (LEP) and Development Control Plan (DCP) for the particular area you are looking to build. The key things to look for are the following;
Can you build a dual occupancy on a sloping block?

Yes you can, we do a large number of dual occupancies on sloping sites, just be careful on which area you develop a dual occupancy in, the costs on a sloping site are always more expensive than a flat block, just make sure it’s not a low socio area where you may overcapitalise. Another key thing to ensure is for stormwater, make sure the block slopes to the street otherwise you will need to get an easement through your neighbouring site should the block be sloping to the rear.


If you are looking for a property investment that doubles your income, doubles your equity growth and maximises the value of your land, then a duplex or dual occupancy development could be a great option for you.

Duplexes and Dual Occupancies are a low cost way of adding value to your existing home site as well as increasing the house density in established older suburbs with great sized house blocks.

With land becoming increasingly more valuable, the duplex and dual occupancy developments are more popular than ever. Duplex Building Design specialises in these kind of developments, hence the name of our business. With our wealth of experience and knowledge we can design a development that has two attached or detached dwellings on one allotment of land. Subject to council’s local environmental plan (LEP) and council approval, your duplex or dual occupancy home may be subdivided as either Torrens or Strata title.
Our main goal is to remove the stress from designing your project and getting the Development Application or Complying Development approved.

Duplex or Dual Occupancy Brief
It’s important you speak with an expert who understands the planning process for a dual occupancy or duplex development. Duplex Building Design takes the stress out of the process right from the beginning. We will look at the following key areas from the initial design brief meeting upon engagement.



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