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Extensions + Additions

As time passes, the number of people living in a house naturally increases, which is where house extensions and designs become a necessity. People have more children who then get older and require more space for themselves.

Upgrade Your Property with House Extensions and Designs

With our home design expertise and detailed knowledge of the Development Application process, we can help you. When you want to create additional areas in your home or reconfigure existing areas, you typically have two options; build out or build up.


Adding extra rooms to the ground floor or building a second storey addition can give your property’s equity a great boost, not to mention the additional space for your growing family or entertaining guests. An attic conversion or a new storey might create more room and privacy for growing teenagers, and may also provide better views to the surrounding outlook, all without reducing the outdoor space that most Aussie families enjoy.


Our house designs to your extension will be sympathetic to your existing home, ensuring a cohesive look which will enhance the resale value on the property.


Building out typically involves adding a room at ground level, which is one of the most popular and cost effective types of additions. These options increase the footprint of your home by extending the house’s perimeter, which offers minimal disruption to the rest of the home.

If you want to expand your living space without increasing the footprint of your home, building up is the option for you. With this type of addition you might convert and extend attic space, add a room or rooms to the second storey, or even add an entire second storey onto the single storey home, as most builders will tell you, extending up is generally more expensive than expanding out so feel free to contact us for more information.


We develop plans for all types of extensions and additions. We prepare the plans from design through to approval delivery..

Stage 1 – Preliminary
Stage 2 – Concept Design
Stage 3 – DA/CDC (Working Drawings)

The Importance of Modern House Extensions

The decision to have a property extended comes around when space is at a premium. A growing family with more children needing their own space is a prime example. Other times, homeowners are bored with their current house and need to refresh it. 

Extensions aren’t only aesthetically pleasing; they are practical. Everyone loves extra space to cook in, or a man cave or even an additional bathroom to avoid those teenage arguments. 


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Common Mistakes People Make Regarding Modern Extensions on Old Houses

Since most people that decide to extend their property are doing it for the first time, there are mistakes that they make. 

  • Having an unrealistic schedule. Modern extensions can take time, especially if it’s a big project. In most cases, the family is occupying the property with the builders working around them; it’s highly likely to take longer. Instead of rushing the process to finish the work and ending up with mistakes everywhere, allow the builders to take their time and get the extension correct. 
  • Failing to research the building company. Having your house extended comes with a decent amount of stress and pressure. Always investigate the company you’re hiring to complete your job and avoid having your project turn into a series of arguments between you and the project manager. Ask other clients who have used a building company about their experiences before confirming to hire them. 
  • Getting the windows wrong. The modern extension will include new windows. However, the mistake people make is that they don’t match those with the older windows, and it results in an unsightly mismatch. Always go for the exact styling of your old windows, so they are uniform. 

These are only some of the mistakes people make when they decide to extend their property. It is avoidable by hiring builders that are reliable and considerate about what you want. 

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What You Gain when Using Duplex Building Design

We have a team with more than 20 years of experience in the industry and have been providing residential clients with a flexible and professional approach to building design. With a significant focus on customer service and high-quality design, we have sourced the latest software to produce 3D plans and design for approval authorities. 

Our team are on hand for the design and drafting of new homes, duplexes, townhouses, granny flats, extensions and dual occupancies, to name a few. Contact us for your free quote and start modernising your home with a new extension. 




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