Dual occupancy and duplex builders in Melbourne's south east

Plenty of families in Wheelers Hill, Glen Waverley, Mount Waverley, Rowville, Noble Park, Keysborough, Berwick and Narre Warren are sitting on a block that can hold two homes instead of one. Older house, generous land, established street.

Dual occupancy is how you unlock that. Two dwellings where there was one, either side by side or front and back, built to the same standard we apply to a single custom home.

Side by side or front and back?

Which layout suits your block comes down to width, orientation and access.

• Side by side. Usually needs a wider frontage. Both dwellings get their own street presence and their own driveway. Generally the stronger resale option.
• Front and back. Suits deeper, narrower blocks. The rear dwelling is accessed by a shared or dedicated driveway down one side.
• Retain and build. Keep the existing house and add a second dwelling behind it. Lower cost, but you are working around a home that was never designed for it.

We work out which of these your block actually supports before you spend money on design.

What decides whether your block works

• Zoning and site coverage. How much of the block you can build on depends on the zone. Neighbourhood Residential is generally 60 percent, General Residential 65 percent, and the Residential Growth, Mixed Use, housing choice and transport zones 70 percent.
• Block size. Around 600 square metres and above is where dual occupancy usually becomes viable. Small second dwellings have their own pathway on blocks under 300 square metres.
• Overlays. Heritage, bushfire, flood and vegetation overlays change what is possible and how long approvals take.
• Easements and covenants. These sit on the title and can restrict where and how high you build, and they catch a lot of people out.
• Access and services. Driveway width, crossovers, and whether services can be split across two dwellings.

The Townhouse and Low-Rise Code, gazetted 6 March 2025 and in operation from 31 March 2025 under Amendment VC267, changed how a lot of these projects are assessed. Clause 54 changed again on 8 September 2025 under Amendment VC282. We work to the current rules, not the ones that applied when your neighbour built.

What shapes the cost

Every block is different, so we do not publish a single price. These move the number most:

• Whether you are demolishing, retaining, or building on vacant land
• Site coverage and how much of the block you can use
• Single or double storey across each dwelling
• Ground conditions, slope and access for machinery
• Level of finish in each dwelling
• Subdivision, planning and authority fees, and splitting services

Under Victorian law any domestic building work over ten thousand dollars needs a major domestic building contract, and work over sixteen thousand dollars needs domestic building insurance. New homes must also meet the seven star minimum thermal performance standard that applied from 1 May 2024.

What you are covered by

Every KGN dwelling comes with a three month defect period, a two year non-structural warranty and a ten year structural guarantee. We return at three months to inspect with you.

Most builds finish within eight to twelve months once approvals and selections are done. Dual occupancy adds time at the front end for town planning and subdivision, and how long that takes depends on your council.

Why owners choose us

KGN Homes is run by the Baloch family from our office and showroom in Noble Park. Sher Baloch, our founder, has a background in structural engineering and forty years in engineering and construction. We take on a limited number of projects each year, so the people who quote your job are the same people who run it.