Duplex builders in Sydney
Thinking of building a new duplex? Duplexes have been our specialty for over 10 years. We tailor dual occupancy homes to your needs and can deliver a complete turnkey solution, whether the design comes from your architect or ours.
What’s included in a turnkey duplex build
- Demolition of existing buildings and outbuildings, and any excavation needed
- Construction of both new dwellings, attached or detached
- Driveways, footpaths and landscaping
- Design and approvals (CDC or DA) if you need them – see design & approvals
Experience that goes beyond building
We’ve designed, built, leased, maintained, sold and lived in duplexes, so we know what makes one work long after handover. That experience shapes the advice we give you at the design stage.
How a duplex build runs
- Free consultation. We visit your site or home, listen to what you want and give honest advice on what’s possible.
- Design and feasibility. Plans that suit your site, budget and the way you want to live, drawn with real building costs in mind.
- Approvals. We work out the quickest approval path, a complying development certificate (CDC) or a council development application (DA), and manage it for you along with all the consultant reports.
- Construction. Built on time and on budget, with Andrew supervising on site and constant communication with you.
- Handover. A final walkthrough together, with every certificate and warranty document handed over.
See our duplexes
What our clients say
“Andrew at AGA Building built two duplexes for me to an exceptional standard — and I managed the whole thing from overseas with complete peace of mind. A to Z project management — delivered on time and on budget, no surprises.”
Carolina G. – two duplexes
★★★★★ 5.0 on Google – read our Google reviews
Duplex FAQs
Can I build a duplex on my block?
Since July 2024, NSW allows dual occupancies in R2 low-density zones with development consent, but minimum lot sizes and other rules vary by council. Read which site is most suitable for a duplex, or send us your address for a free check.
Do you build attached and detached duplexes?
Yes. We build attached dual occupancies that share a party wall and, where the site allows, detached dual occupancies.
Planning a duplex? Book a free consultation
Tell us about your site or home and what you have in mind. We’ll talk through what’s possible, what council is likely to allow and the best next step. No cost, no obligation.