How Much Does It Cost to Build A Duplex In Sydney?


There are more ways to access the equity in your property than to sell and make off with the profits. One strategy many property investors use is to build a duplex, which is two separate homes on a single title, with both dwellings sharing one roof.

Still, you don’t want to break the bank or overcapitalise, so how much does it cost to build a duplex in Sydney?


Reports and surveys

Before you can begin building in Sydney, you will need to have some reporting done on the state of your block. Reports will help you catalogue all your costs, as well as provide preliminary designs.

When dealing with development, reporting can be complicated and time-consuming. Consider using a building cost estimator to help you with this phase of your project. Quality building cost estimators have experience and understand the paperwork associated with the development. As a result, they can significantly speed up this process.


Physical factors of a site


There are many physical factors which will influence the cost of a duplex in Sydney, including:

  • Size and orientation of the block
  • The slope of the land
  • Rock removal
  • Retaining walls

Making yourself aware of the restrictions your block presents, and the additional expenses of modification will help you avoid any unnecessary costs. Again, making use of a building cost estimator’s experience will be a big help in this regard.


Duplex design


There will be many design features which will add to cost of a duplex, such as termite protection, parking areas, fencing, number of bedrooms and living areas, and the quality of kitchen and bathroom fixtures.


The kitchen and bathroom are areas which add the most cost to a duplex development, as the size, design, and range of fixture options is almost limitless. Water and electrical systems may also require upgrading, so they conform to current council standards.

If building a duplex onto an established property, there may also be demolition costs involved if part or all of the property needs removing to make way for the new dwelling.


Is a duplex the best investment?


The cost to build a duplex in Sydney will be more than the price to develop a single dwelling. There are a lot of hidden costs to uncover and factor into the equation before you can decide if a duplex is the most efficient way to maximise your property investment.

As you can see, a duplex development is a significant undertaking, which is why we highly recommend bringing on a building cost estimator as part of your development team to reveal hidden costs and maximise the return on your investment.


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