Granny Flat Rules Tasmania: 2026 Guide (60sqm to 90sqm Reform)

TL;DR: Tasmania currently allows secondary dwellings (granny flats) up to 60sqm or 30% of the main dwelling’s floor area (whichever is less). In March 2026, the government announced a formal process to increase the limit to 90sqm — a 50% jump designed to tackle the state’s housing crisis. Granny flats must share utility connections and can be rented to anyone. Planning permits are not required in most residential zones if the Tasmanian Planning Scheme standards are met.

Key takeaways

• Tasmania’s current granny flat limit is 60sqm or 30% of the main dwelling (whichever is less).
• The government has begun a formal process to increase the limit to 90sqm — expected to take effect later in 2026.
• In most residential zones, a planning permit is not required if the Tasmanian Planning Scheme standards are met.
• A building permit is always required, even when no planning permit is needed.
• Granny flats must share services (electricity, water, sewer, telecom) with the main dwelling.
• There are no restrictions on who can live in a granny flat — rental to anyone is permitted.
• Only one secondary dwelling is allowed per property, and it cannot be sold separately.
• Use the grannyflatcost.com calculator to estimate your Tasmanian granny flat build cost.

What Tasmania calls a “granny flat”

Under the Tasmanian Planning Scheme (TPS), a granny flat is classified as a secondary residence — a self-contained dwelling on the same lot as an existing single dwelling. The key characteristics are:

• Located on the same property as a primary (single) dwelling
• Self-contained (kitchen, bathroom, toilet)
• Shares access, parking, and utility connections with the main dwelling
• Cannot exceed the size limits set by the TPS
• Cannot be subdivided or sold separately from the primary dwelling

“Secondary residence” is the official planning term, though “granny flat,” “ancillary dwelling,” and “backyard dwelling” all get used interchangeably.

Current size rules (as of early 2026)

The Tasmanian Planning Scheme limits secondary residences to:

Requirement	Current rule
Maximum floor area	60sqm
Percentage cap	30% of main dwelling’s total floor area
Applicable limit	Whichever is less
Bedrooms	Typically 1 (practically, due to size constraints)

What this means in practice

The dual limit (60sqm or 30%) catches many homeowners off guard. If your main dwelling is 150sqm, your granny flat is limited to 45sqm — 30% of 150sqm, not 60sqm. That’s a tight space: 45sqm barely fits a one-bedroom layout with a kitchen and bathroom.

For a 60sqm granny flat, your main dwelling needs to be at least 200sqm — a size many older Tasmanian homes don’t reach.

Main dwelling size	Maximum granny flat (30% rule)	Effective limit
120sqm	36sqm	36sqm (studio only)
150sqm	45sqm	45sqm (tight 1-bed)
200sqm	60sqm	60sqm (comfortable 1-bed)
250sqm	75sqm	60sqm (capped)

The 2026 reform: 60sqm to 90sqm

In March 2026, Tasmania’s Minister for Housing and Planning Kerry Vincent announced that the government has started a formal process to amend the Tasmanian Planning Scheme and increase the maximum granny flat size from 60sqm to 90sqm.

Why the change?

Minister Vincent stated: “We need to be coming at housing from all angles. Having a small, self-contained dwelling located on existing blocks represents low-hanging fruit as we look to increase our medium-density housing stock.”

The key reasons behind the reform: the current 60sqm limit typically only allows a single bedroom once a kitchen and bathroom are included; a 90sqm limit would enable genuine two-bedroom granny flats; Tasmania faces acute housing affordability and rental shortage pressures; and the Housing Industry Association (HIA) has reported builders expect to construct ten times more granny flats in 2026 than in 2022.

What the 90sqm change enables

Layout	Current (60sqm)	Proposed (90sqm)
Studio/open plan	Comfortable	Very spacious
1 bedroom	Comfortable	Spacious with study nook
2 bedrooms	Not practical	Comfortable
2 bed + separate living	Not possible	Achievable

When will the 90sqm rule take effect?

The formal amendment process has begun but isn’t finalised. The typical timeline for Tasmanian Planning Scheme amendments:

1. Initiation (completed March 2026)
2. Public exhibition and submissions (typically 28–60 days)
3. Tasmanian Planning Commission review
4. Minister’s decision
5. Gazettal and commencement

Realistically, expect the new 90sqm limit to take effect in late 2026. Until it’s gazetted, the current 60sqm/30% rules remain in force.

Should you wait?

If you are designing a granny flat now, your options are: design to the current 60sqm rules if you want certainty and a fast start; design at 90sqm if you can tolerate a delay and planning risk; or design a 60sqm flat that could be extended later as a compromise. It’s also unclear whether the 30% cap relative to the main dwelling will remain under the new rules. Monitor progress on the Tasmanian Planning Commission website.

Planning permit requirements

When you do not need a planning permit

In most residential zones (General Residential, Inner Residential, Low Density Residential), a planning permit is not required for a secondary residence if the property already contains a single dwelling, the secondary residence meets all Acceptable Solutions in the relevant zone, no applicable overlays trigger a permit requirement, and the secondary residence meets setback, height, and size requirements.

When you do need a planning permit

A planning permit is required if the proposed granny flat doesn’t meet one or more Acceptable Solutions, the property is affected by flood, bushfire, heritage, or landslide overlays, the property is in a zone where secondary residences require discretionary assessment, or you’re proposing something larger or taller than the Acceptable Solutions allow.

Building permit is always required

Even when no planning permit is needed, a building permit is mandatory. This ensures the structure complies with the National Construction Code for structural adequacy, fire safety, weatherproofing, energy efficiency, and accessibility. A building permit is obtained through your local council or a private building surveyor.

Setback and site requirements

Setback requirements vary by zone, but typical standards for residential zones in Tasmania are:

Setback	Typical requirement
Front boundary	4.5 metres (or consistent with existing streetscape)
Side boundary	1.5 metres minimum
Rear boundary	3 metres minimum
Distance from main dwelling	No minimum specified, but fire separation requirements apply

A few things worth knowing: setbacks can vary significantly between zones and councils, some zones allow reduced setbacks for outbuildings and secondary residences, battle-axe lots have specific access handle requirements, and properties on slopes may face additional setback requirements. Always check the specific Acceptable Solutions for your zone.

Shared services requirement

Secondary residences must share connections and meters with the main dwelling for electricity (no separate meter or connection), water (shared TasWater connection), sewer (shared TasWater connection), and telecommunications. Access and parking arrangements are also shared.

Your granny flat’s utilities run through the main dwelling’s infrastructure. Many landlords either include utilities in the rent or install sub-meters for internal tracking, though the formal connection remains shared.

Rental rules

Tasmania has no restrictions on who can live in a secondary residence. You can rent your granny flat to family members, friends, or unrelated tenants — anyone at all. The tenant has standard residential tenancy rights under the Residential Tenancy Act, with no requirement for the occupant to be elderly, disabled, or related to the property owner.

Construction access and site considerations

Tasmania’s varied terrain creates real site challenges for granny flat construction.

Steep blocks — Many Tasmanian properties, particularly in Hobart, Launceston, and coastal areas, have significant slopes. This can add $20,000–$50,000+ to construction costs for retaining walls, stepped footings, or suspended slabs.

Rock — Dolerite (the rock that forms Mt Wellington/kunanyi) is common across much of southern Tasmania. Excavation through rock is significantly more expensive than standard earthworks.

Heritage overlays — Many Hobart suburbs (Battery Point, Sandy Bay, North Hobart) and Launceston areas (Trevallyn, West Launceston) have heritage overlays that impose design restrictions.

Bushfire zones — Large parts of the Tasmanian urban fringe are designated bushfire-prone. This triggers a Bushfire Attack Level (BAL) assessment and may require specific construction methods and materials.

Limited access — Narrow side access is common on older Tasmanian properties. A minimum of 1.5m wide by 2.1m high is typically needed for construction access.

Cost estimates for Tasmanian granny flats

Based on current Tasmanian construction costs:

Component	Estimated cost range
Design and plans	$3,000 – $8,000
Council/planning fees	$500 – $2,000
Site preparation	$5,000 – $30,000 (heavily slope-dependent)
Construction (60sqm)	$120,000 – $180,000
Utility connections	$5,000 – $15,000
Landscaping and finishing	$5,000 – $15,000
Total (flat site)	$140,000 – $220,000
Total (sloping site)	$170,000 – $270,000

These are indicative figures. Use the grannyflatcost.com calculator for a more precise estimate tailored to your Tasmanian property, accounting for local builder rates, site conditions, and the specific design you have in mind.

How Tasmania compares to other states

Feature	Tasmania (current)	Tasmania (proposed)	NSW	Victoria	SA
Max size	60sqm / 30%	90sqm (TBC)	60sqm	60sqm	70sqm
Min lot size	No minimum	TBC	450sqm	No minimum (300sqm for permit exemption)	600sqm (DTS)
Planning permit	Usually not required	TBC	CDC or DA	Usually not required (300sqm+)	Always required
Rental to anyone	Yes	Yes	Yes	Yes	Yes
Shared services	Required	TBC	Not required	Not required (no gas)	Required

If the 90sqm reform passes, Tasmania will have the largest permitted granny flat size of any Australian state, alongside Queensland councils that allow up to 90sqm in rural residential zones.

Frequently asked questions

Can I build a granny flat and rent it on Airbnb?

Technically yes — there are no occupancy restrictions on who lives in the secondary residence. However, some councils may have separate short-stay accommodation rules. Check with your local council before listing.

Does the 30% rule apply to the main dwelling’s internal area or total footprint?

It applies to the total floor area of the main dwelling as defined in the Tasmanian Planning Scheme — the gross floor area of the primary dwelling.

Can I subdivide the granny flat onto its own title?

No. A secondary residence must remain on the same title as the primary dwelling. It cannot be strata-titled or sold independently.

Can I build a granny flat on a vacant lot?

No. There must be an existing single dwelling on the property before a secondary residence can be built. Main house first, then the granny flat.

Will the proposed 90sqm limit also change the 30% cap?

This hasn’t been confirmed. The March 2026 announcement focused on the absolute size increase. Whether the 30% proportional cap will be adjusted or removed is unclear and will be determined during the formal amendment process.

Do I need a soil test?

Yes. A soil test (geotechnical report) is required for any building permit application. It determines the footing design required for your specific site conditions. In Tasmania, expect to pay $500–$1,500 for a soil test.

Next steps

1. Check your property’s zone and overlays on the LIST Map — Tasmania’s spatial data portal
2. Measure your main dwelling to calculate your 30% cap under current rules
3. Estimate your costs using the grannyflatcost.com calculator
4. Monitor the 90sqm amendment on the Tasmanian Planning Commission website
5. Engage a local designer experienced with Tasmanian residential regulations

Tasmania’s granny flat rules are shifting. Whether you build under the current 60sqm rules or wait for the proposed 90sqm expansion, working through these regulations is the essential first step toward adding a secondary dwelling to your property.