Small Second Dwellings in Victoria: Planning Rules for a Second Home on a Residential Lot

What it is

A small second dwelling in Victoria is a self-contained residence of 60 square metres gross floor area or less, sited on the same lot as an existing dwelling. The unit must include a kitchen sink and food preparation area, a bath or shower, a toilet plus a wash basin. The Victorian Building Authority defines this product class on its consumer page and in fact sheet PES-1 issued in August 2024 [1][2]. The framework sits inside the Planning and Environment Act 1987 (Vic) and the Victoria Planning Provisions, with parallel changes to the Building Regulations 2018 [3].

The category replaces the older Dependent Person's Unit pathway for new builds. A transitional period lets builders continue to use DPU rules in parallel until 28 March 2027 under the Victoria Planning Provisions amendment that took effect in 2024 [2]. Before the reforms, a second dwelling on a residential lot generally needed a planning permit triggered by the Residential Growth Zone or the General Residential Zone provisions of the relevant planning scheme.

Why the 2024 reforms matter for residential builders

The statewide reforms removed the planning permit requirement for most lots that meet the size and siting tests. A building permit is still required and the small second dwelling still has to comply with Part 4 of the Building Regulations 2018 plus the Plumbing Regulations 2018 [2]. The reform package forms part of Victoria's Housing Statement response, which the Department of Transport and Planning has progressively rolled into the planning system since late 2023 [3].

For a builder taking a contract on a residential lot, the practical effect is faster site start. The planning permit pathway that previously added several months has been removed for compliant projects. The trade-off is that the siting rules in the planning scheme still apply and the lot itself must already contain a lawful dwelling.

Lot eligibility and siting

A small second dwelling can be built on a lot already containing a dwelling in the Neighbourhood Residential Zone, the General Residential Zone, the Residential Growth Zone, the Mixed Use Zone, the Township Zone, the Low Density Residential Zone or specified rural zones. The lot must have a minimum area set by the relevant zone provisions, with the standard floor being 300 square metres in most residential zones [4].

Siting controls in Clause 54 of the Victoria Planning Provisions continue to apply. These cover street setback, side and rear setbacks, walls on boundaries, daylight to existing windows plus overshadowing of recreational private open space. Builders working in heritage overlay or environmental significance overlay areas should expect the overlay trigger to bring the permit requirement back in [4].

What the building permit covers

The building surveyor checks structural adequacy, fire separation from the existing dwelling, energy efficiency under NCC Volume Two and the 7-star NatHERS pathway, smoke alarms plus wet area waterproofing. Standalone water and sewer connection rules under the relevant water authority still apply.

Contracts and consumer protection

The Domestic Building Contracts Act 1995 (Vic) covers any small second dwelling job where the contract value exceeds the threshold for major domestic building work. The builder must hold a registered building practitioner class that matches the work scope, must issue an HBI Domestic Building Insurance certificate where the contract price exceeds the Domestic Building Insurance threshold and must follow the prescribed contract clauses [5].

Consumer Affairs Victoria publishes guidance for owners on the deposit cap, progress payment caps and the cooling-off rules that apply to these contracts. Builders should provide that information up front and keep the file showing the consumer received it [5].

Common compliance traps

Three issues recur on small second dwelling jobs in Victoria. The first is treating the unit as a non-habitable shed during early framing, which forces a later building permit amendment plus inspection. The second is assuming the small second dwelling can be sold as a separate title without first applying for subdivision under the Subdivision Act 1988 (Vic). The third is connecting plumbing without a licensed plumber issuing a Certificate of Compliance under the Building Act 1993 (Vic) and the Victorian Building Authority plumbing scheme.

Renting the second dwelling

The reform package allows the small second dwelling to be rented to any occupant, not only a dependent of the primary household. That means a Residential Tenancies Act 1997 (Vic) lease applies once the unit is leased to a non-household member [1]. Builders frequently get asked about minimum standards for rented premises under that Act; the unit must meet the rental minimum standards in the Residential Tenancies Regulations 2021 (Vic) before first occupation.

Short stay accommodation use is a separate question and depends on the planning scheme zone plus any overlay. Builders should refer that question to the owner's planner rather than guess.