Dual Occupancy and Subdivision in Melbourne: Minimum Lot Sizes, Garden Area, and What the 2025–26 Reforms Changed

What the Subdivision Act 1988 actually does — and does not do

The Act's stated purpose is procedural: to set out the procedure for the subdivision and consolidation of land, including buildings and airspace, and for the creation, variation or removal of easements or restrictions; and to regulate the management of and dealings with common property, and the constitution and operation of owners corporations.

That is the whole of it. A full-text reading of the authorised version of the Act — version 084, incorporating amendments as at 1 July 2026 — returns no occurrence of "minimum lot", "lot size", "minimum area", "minimum size", "square metre", "hectare" or "frontage" anywhere in its 147 pages. The Planning and Environment Act 1987 likewise contains none. The Subdivision Act tells you how to lodge a plan of subdivision, who the referral authorities are, how easements are created and removed, and how an owners corporation works. It does not tell you whether your land can carry two lots.

The corollary matters as much as the finding: because the Acts are silent, every lot-size number in the Victorian system lives in the planning scheme — in a zone clause or in a schedule to a zone. That is why the answer changes at council boundaries, and sometimes at street level.

This matters because the "600 m² minimum" that circulates on forums and in agent marketing is presented as though it were legislated. It is not. It is a rule of thumb — a reasonable one in many parts of Melbourne, because 600 m² is often about the point where a compliant two-lot design starts to work — but it is a rule of thumb, and quoting it as law leads people to dismiss blocks that would work and to pay premiums for blocks that will not.

Where the minimum lot size really comes from

This is where nearly every published guide, including some written by people who should know better, goes wrong. It is not true that "each residential zone lets a schedule specify a minimum lot size". Among the residential zones the provision exists only in the Neighbourhood Residential Zone, at Clause 32.09-3: "A schedule to this zone may specify a minimum lot size to subdivide land. Each lot must be at least the area specified for the land, except where an application to subdivide land is made to create lots each containing an existing dwelling or car parking space, where an application for the existing dwelling or car parking space was made or approved before the approval date of the planning scheme amendment that introduced this clause 32.09 into the planning scheme." The General Residential Zone (32.08-3) and the Residential Growth Zone (32.07-3) contain no minimum lot size provision at all — their subdivision clauses run permit requirement, then garden area (GRZ only), then the Clause 56 requirement, then VicSmart.

The operative words in the NRZ provision are "may specify". Where a council has specified a minimum in its NRZ schedule, that number binds. Where it has not — and in the GRZ and RGZ, where the provision does not exist — there is no numeric minimum to satisfy. That does not mean anything can be subdivided; it means the constraint is somewhere else.

Outside the standard residential zones the position is different again, and several zones do carry a state-wide default that applies when a schedule is silent: the Low Density Residential Zone default is 0.2 hectare where the lot is connected to reticulated sewerage and 0.4 hectare where it is not; Rural Living is 2 hectares; the Green Wedge A Zone is 8 hectares; and the Green Wedge, Rural Conservation and Farming Zones are 40 hectares. If your land is in one of those, there is a number — it is simply not the number people quote for suburban blocks.

To find the answer for a specific address you need three things, in this order: the planning property report for the address, which tells you the zone and every overlay; the schedule to that zone in your council's planning scheme, which tells you whether a minimum lot size has been specified; and then the garden area, height and assessment-clause tests, which are where most proposals actually fail.

This is also why a buyer should never take a vendor's "subdividable" or "development potential (STCA)" at face value. STCA means "subject to council approval", and it is a statement about the vendor's hopes rather than about the land.

The garden area requirement — the feasibility killer

Mandatory garden area applies in exactly two zones — the General Residential Zone and the Neighbourhood Residential Zone — and it is, in our experience, the provision that most often kills a townhouse feasibility. It applies to an application to construct or extend a dwelling, small second dwelling or residential building, and it requires a minimum percentage of the lot to be set aside as garden area. Planning Practice Note 91 (January 2026) states the scope in the same terms: "A minimum garden area requirement is a mandatory requirement that applies to all lots in the NRZ and GRZ that are 400 square metres or more."

The bands are widely misquoted, so here they are exactly as the clause states them:

Lots under 400 m²: a separate garden rule, in a different clause

The subdivision clause imposes its own garden requirement that the dwelling clause does not. An application to subdivide land that would create a vacant lot of less than 400 m² capable of development for a dwelling must provide at least 25% garden area on each such lot.

So sub-400 m² lots do catch a garden requirement — through the subdivision clause (32.08-3 and its equivalents, sourced to Amendment VC288, gazetted 18 September 2025 and operative 16 October 2025), not through the dwelling clause (32.08-4). This is precisely the distinction where most published guides are wrong, and getting it wrong in either direction is expensive: assume the requirement does not apply and your plan of subdivision fails; assume 32.08-4's 35% applies to a 380 m² lot and you have sterilised land that did not need to be given up.

There are exemptions to the dwelling-side garden requirement, and they are narrow: where the schedule to the zone specifies otherwise; where the land is identified as a medium density housing site in an approved precinct structure plan, incorporated plan or approved development plan; and for alterations to a building that already did not comply at the approval date of Amendment VC110.

The Residential Growth Zone has no garden area requirement at all

Clause 32.07, the Residential Growth Zone, contains no garden area provision. Not a lower percentage — none. That is a structural difference from the General Residential Zone and the Neighbourhood Residential Zone, and on a medium-density proposal it is often worth more than any other single planning attribute of the land.

It is also why "what zone is it" is the first question to ask about a development site and "how big is it" is the second. An RGZ block of 600 m² and a GRZ block of 600 m² are not the same asset, and the difference does not show up in the listing.

Height limits by zone — and which ones are mandatory

The second hard cap is height. What most people miss is that the zones differ not only in the number but in whether the number is mandatory or discretionary. The Residential Growth Zone is the one that is discretionary by default, and it has been for some time — the "should not exceed 13.5 metres" wording predates the 2026 Mid-Rise Code reform rather than arriving with it.

• A "large site" means a lot of at least 1,000 m² with a frontage of at least 20 m, or two or more contiguous lots with a combined area of at least 1,000 m² and a combined frontage of at least 20 m. Note the term is defined only for the table to Clause 32.10-8 — it is not a VPP-wide definition and does not carry into other clauses.
• A one-metre allowance applies where the natural ground level slopes more than 2.5 degrees across any cross-section wider than 8 metres of the site of the building.
• A basement is not counted as a storey.
• A building may also match the height of a pre-existing or lower abutting building in the circumstances the clause specifies.
• The RGZ provision expressly replaces the maximum building height specified in Clauses 54.02-2 and 55.02-2 — so on RGZ land the zone number governs, not the assessment clause number.

Which assessment clause applies to your proposal — this changed in 2026

This is the section where almost every pre-2026 guide is now wrong, because the clause boundaries moved. As at August 2026:

Clause 56: residential subdivision, and why a two-lot split is not assessed like a 60-lot estate

Clause 56 is the residential subdivision clause. It applies to subdivision in the Neighbourhood Residential, General Residential, Residential Growth, Housing Choice and Transport, Mixed Use and Township zones, and in any Comprehensive Development Zone or Priority Development Zone that provides for residential development. It does not apply to a subdivision into lots each containing an existing dwelling or car parking space.

The part almost nobody publishes is that the standards scale with the number of lots. A two-lot subdivision is not assessed against the same body of standards as a greenfield estate, and knowing which standards actually apply is the difference between a proportionate application and an over-engineered one.

The 2025–26 reform wave, decoded

Seven amendments in sixteen months changed the residential planning framework more than the previous decade did. Briefly, so you can tell which one a given article predates. Two dates matter for each and they are routinely conflated: the gazettal date, and the operative date on which the new provisions began to apply. Where they differ we give both.

1. VC257, gazetted 25 February 2025 — the activity centres reform. Inserted Clause 32.10 Housing Choice and Transport Zone and Clause 43.06 Built Form Overlay into every planning scheme in the state, and reissued Clause 56.
2. VC267, gazetted 6 March 2025 and operative 31 March 2025 — the townhouse and low-rise code. Rewrote Clause 55 and restructured the residential zones. The two dates are routinely conflated; 31 March is the date the new provisions began to apply.
3. VC282, gazetted 11 August 2025 and operative 8 September 2025 — restructured Clause 54, brought small second dwellings into it, and moved the small second dwelling permit triggers into standalone zone clauses. VC292 (11 September 2025) followed with a single omitted cross-reference.
4. VC288, gazetted 18 September 2025 and operative 16 October 2025 — its published purpose is extending VicSmart to two dwellings on a lot and two-lot subdivision, but it is also the amendment in which the subdivision clauses first carry the prohibition on creating a separate lot for land containing a small second dwelling, and the sub-400 m² garden rule. Cite the gazetted ordinance for that, not the explanatory report, which does not mention it.
5. VC300, gazetted 19 March 2026 and operative 16 April 2026 — the Mid-Rise Code. Split the multi-dwelling assessment clauses by height: Clause 55 for three storeys or less, new Clause 57 for four to six storeys, Clause 58 for apartments.
6. VC308, gazetted and operative 17 April 2026 — the correcting amendment nobody cites, and the reason a guide written on the day VC300 commenced is already a day stale. It updated the Mixed Use, Township and Residential Growth zone schedules to align with the Mid-Rise Code and corrected technical errors in VC300, reissuing seven Clause 57 sub-clauses in the process.
7. VC312, gazetted and operative 16 June 2026 — corrections and updates, including Clauses 53.23-2 and 53.25-1. This is the current state of the Victoria Planning Provisions: as at 31 August 2026 there is no VC313.

Dual occupancy versus a small second dwelling — two different products

In Victorian planning terms a dual occupancy is simply two dwellings on one lot, assessed under Clause 55 where it is three storeys or less. It has no size cap, it can be designed as two comparable dwellings, and — subject to the zone schedule, the overlays and a compliant design — it is the pathway that can end in two separate titles.

A small second dwelling is a different thing entirely: capped at 60 m² gross floor area, assessed under Clause 54, and expressly incapable of being subdivided off. The zone clauses provide that a permit must not be granted which would allow a separate lot to be created for land containing a small second dwelling.

That distinction drives the investment decision. A second dwelling is a rental income and valuation play on one title, with a much lower capital requirement and no planning permit on most lots. A dual occupancy is a development play with a planning permit, a construction program and, if it completes, two saleable assets. They are not two versions of the same strategy and they suit different balance sheets entirely.

What stops a subdivision even when the numbers work

Zone and lot size get all the attention; overlays do most of the killing. A heritage overlay can prevent demolition of the existing dwelling, which is usually fatal to a rear-lot plan that needed the driveway. An environmental significance or vegetation protection overlay can make the removal of a single tree the determining issue. A land subject to inundation or special building overlay changes floor levels and drainage design and can make a small lot uneconomic. A development plan overlay requires a council-approved plan for the wider area before any application can be decided, which is a timing problem rather than a design one — but on a marginal feasibility, timing is the design.

Every one of these is disclosed on the planning property report for the address. There is no excuse for discovering one after you have exchanged, and yet it is the single most common expensive surprise we see.

Windfall Gains Tax if the land is rezoned

If a rezoning increases the value of your land, Victoria taxes the uplift. The Windfall Gains Tax commenced on 1 July 2023. An uplift of not more than $100,000 is nil; more than $100,000 but less than $500,000 is taxed at 62.5% of the part of the uplift above $100,000; and an uplift of $500,000 or more is taxed at 50% of the whole uplift. The two upper rows meet exactly at $500,000 — there is no cliff at the boundary, which is a point commonly got wrong. The rates have not been amended since enactment and are not indexed.

The liability can be deferred, with interest, until the next dutiable transaction, a relevant acquisition in a landholder, or for up to 30 years — three triggers, not two. Where the tax is payable rather than deferred, payment is due within 30 days of the trigger.

One provision to know before you negotiate a contract: the Windfall Gains Tax cannot be passed on to a purchaser by agreement. Section 10H of the Sale of Land Act 1962 makes that unenforceable, so a vendor cannot contract out of it and a purchaser should not accept a special condition purporting to shift it.

This is a rezoning tax, not a subdivision tax — subdividing land within its existing zone does not trigger it. But if your development thesis depends on a rezoning happening, the tax is a first-order item in the arithmetic rather than a footnote, and the deferral option is what makes many rezoning-dependent holdings workable at all.

What our own transaction record says about lot sizes

Across the 345 transactions we publish as open data, the median land size is 652 m² — which puts the typical property we buy in the 35% garden area band, the tightest of the three. That is not a coincidence: 600–700 m² is the band where a second dwelling works comfortably and a two-lot subdivision starts to become arguable, which is why so much investor competition sits there.

It is also a caution. A 652 m² block that must give up 35% of its area as garden has roughly 424 m² to work with across both the existing dwelling and anything new, before setbacks. The garden requirement scaling upward with lot size means the marginal 50 m² of land you paid for buys you less developable area than you would expect.