Duplex Mortgage Australia 2026 — Finance Both Sides of a Duplex

General information only — not financial advice. This content is intended as educational guidance. Consult a qualified financial adviser, mortgage broker, or legal professional before making financial decisions. See our full disclaimer.

Buying a duplex on one title is treated as standard residential lending with rental income from the second dwelling assessed at 70–80%. Building requires a construction loan with progressive drawdowns.

Frequently Asked Questions

Can I live in one side and rent the other?

Yes — this is a common strategy. You occupy one dwelling as your principal residence and rent the other. The rental income can count toward your serviceability. The rented side will have CGT and income tax implications.

What is the minimum block size to build a duplex in Australia?

NSW requires 600m² total in many councils for a CDC duplex. QLD and VIC also have 600–800m² minimums in standard residential zones. Check local council zoning rules before purchasing a block for duplex development.

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