What Is a Duplex and How Can You Develop One?


A duplex is simply a residential dwelling with two homes sharing a common wall in the middle. Each side has its own entrance and amenities, such as laundry and garage. This option can offer several advantages for the person wanting to develop a vacant block or tear down and rebuild a single occupancy home.

A duplex gives you flexibility

Having two properties side by side gives you a range of options.

  • You can live in one side and have family members live next door. This could be the best choice if you have older parents or grown children who want to live nearby.
  • You can rent out one side to generate income and live on the other side or rent out both and receive two rental incomes from the property.
  • You could sell both sides of the duplex.

If developing on a block of land, a duplex opens up a range of possibilities that you won’t get from building a single occupancy home. For investors, the land cost will be split between two homes

Legal and regulatory considerations

A duplex can be on one title or two titles. Having two titles will make it possible to sell each side as a separate home – or keep one and sell one if that’s what you choose to do. Although there will be additional costs for subdividing, the benefits will make it worthwhile by making it possible to sell the residences as separate properties.

Local councils will have different rules for approving duplex developments. Zoning is also an important factor that will determine whether dual occupancy is an option in a particular area. Councils will have requirements for factors such as the width of the block frontage, block dimensions, site orientation, house footprint coverage, and driveway crossovers. The approval process can be complex, so it’s important to work with an architect or builder who will manage the council approval process. Silverline Homes can assist you with this if needed.

Options for developing a duplex

If you have a block of land or a single occupancy dwelling that you plan to tear down, an architect can design the project and then work with a town planner to get council approval.

At Silverline Homes, we work with many clients who have completed and approved plans which we build from. This includes duplexes and other forms of multiple occupancy developments.

If you have a block land or dwelling and need advice and consulting, Silverline Homes can provide the full service, from determining feasibility, getting the project design, managing the council approval process, and building the dual occupancy residence.

Understand the steps for duplex development

Here is a brief list of the common steps to follow for developing a duplex:

  • Seek initial pre-approval for financing.
  • Learn about the local environmental plan and the development control plan of the local council.
  • Conduct project feasibility study prior to committing yourself to the project to ensure the financial benefit with the best outcome. 
  • Appoint an architect of your choice or have Silverline Homes to undertake the process on your behalf to go through the council zoning and planning regulations to make sure that there are no covenants on the land title nor council restrictions that could hinder the project.
  • Once you have met the town planning compliance requirements, have Silverline Homes look at the initial proposed plans for general feedback to ensure all parties are on the same page to achieve adequate design to fits your goals.
  • Secure the final loan approval for duplex development.
  • Once the town planning permit has been obtained for the development, Silverline Homes can liaise to arrange all building documentation, reports, service providers permit as well as obtaining the building permit which will ease any stress attached to go through such a detailed process.    
  • Start duplex construction.
  • Apply for a subdivision certificate.

These steps can vary depending on your particular circumstances, such as if you are tearing down and existing residence you own or already own a block of land. Whatever step you are in the duplex development process, Silverline Homes is ready to assist.

Townhouses, Knockdown Rebuild or Duplex Development

Project Modelling

We can arrange for a project model to replicate the exterior and interior of the project which real estate agents love as it assists them to better rent or sell your property.

Liaising with Service Providers

We will be delighted to help you foresee requirements that you may not be aware of and assist with your decision making on areas such as Melbourne water consent, water board PIC consent, owner corporation insurance and town planning inspections


We have a crew of demolition contractors and asbestos removal experts who take care in the demolition process including council asset protection with the demolition permit.

Our staff can also help add a personal touch to your project by letting you choose from a range of internal and external colours and finishes from our beautiful showroom.