Imagine a homeowner in Melbourne's inner east with a weatherboard house, a deep backyard and a Heritage Overlay affecting the property. There appears to be enough room for a compact granny flat. Then two opposite answers arrive: one person says heritage means it cannot be built, while another says a granny flat under 60 m² never needs a planning permit.
Neither answer is reliable on its own.
Victoria has a specific Heritage Overlay exemption for some small second dwellings. But the exemption has conditions, and it does not automatically clear every other planning control or every piece of work needed to deliver the project.
The short answer
A Heritage Overlay is not an automatic refusal and does not always mean a planning permit is required for the small second dwelling itself.
Under Victoria's small second dwelling framework, a planning permit is not required under the Heritage Overlay when:
- the building height does not exceed 5 metres; and
- the building is finished in muted tones and colours.
If either condition is not met, a planning permit is required under that overlay. A building permit is still always required.
The important words are "under the Heritage Overlay". Your zone, another overlay, the size of the lot, earthworks or associated demolition may create a separate planning question. Our broader Granny Flat Rules Victoria guide explains how these layers fit together.
Why heritage does not give a simple yes or no
A Heritage Overlay protects a place or precinct identified in the local planning scheme. The schedule to Clause 43.01 lists the affected properties and may identify extra controls. The heritage study or statement of significance explains what is important about the place.
That matters because two properties with the same "HO" label can have different contexts. One may be part of a streetscape where the front house is the main heritage element. Another may contain an individually significant building, outbuilding, fence or garden element.
The correct starting point is therefore not the colour of the proposed granny flat. It is the property's complete planning position. A Land Eligibility Check should identify the zone, every overlay and the relevant schedule before a floor plan is treated as suitable.
The exemption is not a whole-property approval
Meeting the 5-metre and muted-colour conditions can remove the permit requirement under the Heritage Overlay for the small second dwelling. It does not necessarily remove approval requirements created by:
- another overlay, such as a Significant Landscape Overlay or flood-related control;
- a residential-zone trigger, including relevant requirements for smaller lots;
- earthworks, vegetation removal or work within a protected area;
- a separate demolition or alteration affecting a heritage element; or
- siting and design requirements assessed through the planning or building system.
This is why the phrase "no planning permit" should only be used after the complete address and complete scope have been checked. The Council Approval Guide is useful for understanding which authority considers each part of the project.
Check the work around the granny flat
The new dwelling is only one part of the build. A design may rely on other work that has its own heritage or planning consequences.
Removing an old garage or shed
A rear garage may look unimportant, but it should not be assumed to be exempt from heritage controls. Check the Heritage Overlay schedule, statement of significance and council advice before demolition is included in the programme.
Altering a front fence or crossover
Construction access may require a wider gate, fence changes or a different vehicle path. These works can affect the part of the property most visible from the street. Resolve the access strategy before ordering a standard plan.
Removing or working near trees
Trees may be relevant under the Heritage Overlay schedule, another overlay or local law. Even when removal is not proposed, foundations and service trenches can affect root zones.
Running services through a sensitive area
Water, sewer, electricity and stormwater routes may require excavation beside the existing house or through established garden areas. A low-risk dwelling location can become a higher-risk project if the service route is not considered at the same time.
The practical lesson is to assess the whole property path, not just the final building footprint. This is also why the construction sequence in How We Build begins with site information rather than finishes.
Design decisions to settle before detailed drawings
For a heritage-affected block, resolve these questions early:
- Is the proposal genuinely a small second dwelling? It must have a gross floor area of 60 m² or less, be on the same lot as an existing dwelling and operate as a self-contained residence.
- Will the height remain at or below 5 metres? Measure the proposed building correctly in relation to the site and final levels.
- What do muted tones and colours mean for the exterior? Record the proposed roof, wall, trim and visible service colours instead of leaving them as an undefined future selection.
- Does the location minimise disruption? Consider the existing house, significant elements, trees, access, drainage and service routes together.
- Are separate works required? List demolition, fence changes, tree work, excavation and utility connections as part of the approval review.
These choices also affect cost. A design that avoids unnecessary demolition or difficult service routes may reduce uncertainty, while a permit, specialist advice or constrained access may add scope. Use the Granny Flat Cost Victoria guide to compare a building price with the complete property-specific project.
A practical seven-step check
- Obtain the current Planning Property Report or VicPlan information for the address.
- Record the Heritage Overlay number and check its schedule.
- Find the relevant heritage citation or statement of significance.
- Check the zone and every other overlay, not only heritage.
- Test the dwelling height, external colours and floor area against the specific exemption.
- List all enabling works, including demolition, trees, fences, access, drainage and services.
- Confirm the planning pathway, then engage the building-permit process with the relevant professionals.
Do not rely on a nearby approval or a generic online answer. Planning controls attach to the property, while the approval pathway also depends on what you propose to build and remove.
Check the property before choosing the plan
A Heritage Overlay may narrow the design and approval pathway, but it does not automatically make a granny flat impossible. The useful question is whether the proposed small second dwelling meets the specific exemption and whether any other part of the project still needs approval.
MPLUS can review the initial planning context, usable space, access and obvious site constraints before you commit to a design. Start with a Free Land Check.
