If your family is outgrowing your home, but the thought of moving feels overwhelming, you’re not alone. More Launceston homeowners are asking “how much to extend a house” than ever before. With Tasmania’s property market staying strong and the hassle of selling, many are choosing to build onto their existing homes instead of relocating.
The cost to extend a house in Tasmania in 2025 typically ranges from $2,500 to $6,000 per square metre, depending on what you’re building and the level of finish you choose. That puts a standard 40 square metre ground floor extension between $100,000 and $240,000. But there’s more to the story than a simple price tag.
Key Insights
- Ground floor extensions: $2,500–$4,000 per m² (Tasmania typically 10-25% cheaper than Melbourne or Sydney).
- Second storey additions: $3,000–$4,500 per m² (more complex due to structural work).
- Permits required: Most house extensions in Launceston need planning and building approvals from the City of Launceston Council.
- Total project costs: Expect $100,000–$300,000+, depending on size and specifications.
- Timeline: 3–6 months for ground floor, up to 9 months for second-storey additions.
How Much to Extend a House in Tasmania
Ground floor extensions across Australia range from $2,500 to $4,000 per square metre in 2025, while second-storey additions cost between $3,000 and $4,500 per square metre. For Tasmania specifically, costs can extend up to $6,000 per square metre for high-end builds with premium materials and complex designs.
Regional building can be 10-30% cheaper than capital cities due to lower land costs and reduced labour rates, though material transport costs and limited contractor availability can offset some savings. For Launceston homeowners, this means you’re generally working with more competitive rates than Sydney or Melbourne, though costs have still risen across the board.
What Affects Your Extension Costs
Size and Complexity
A simple rectangular extension costs less than one with complex angles, multiple roof lines, or structural challenges. Every corner, every change in roof pitch, every custom detail adds to both materials and labour.
Room Type
Bedrooms and living spaces are straightforward. Kitchens and bathrooms? They’ll push your per-square-metre cost up by 30-50% due to plumbing, waterproofing, electrical work, and expensive fixtures like tapware and cabinetry.
Your Site
Sloping blocks can add $15,000-$100,000+ depending on the gradient and required earthworks, with steep blocks potentially needing retaining walls costing $200-$800 per square metre. Heritage overlay? Expect additional design requirements. Bushfire-prone sites may require additional assessments that add time and cost to your project.
Finishes and Fixtures
The gap between builder’s standard finishes and premium selections is massive. Stone benchtops, quality tapware, hardwood flooring, and double glazing can easily add $20,000–$50,000 to a project.
Energy Efficiency
Tasmania’s climate means proper insulation isn’t optional. Better windows, insulation, and heating systems cost more upfront but save thousands in running costs over the years.
Permits and Approvals in Launceston
Here’s what many homeowners don’t budget for: the approval process. In Launceston, most extensions need both planning and building permits from the City of Launceston Council.
For permitted applications that meet all acceptable solutions, you’ll receive approval within 28 days. Discretionary applications take up to 42 days. The cost? Planning permit fees typically range from $1,000 to $3,000, depending on the project value.
You’ll also need a licensed building surveyor to assess your design and ensure it complies with the National Construction Code and Tasmanian legislation. Their fees generally run $2,000–$3,500 for residential extensions.
Don’t forget these additional costs when working out how much to extend a house:
- Structural engineer reports: $2,000–$3,200
- Soil testing (if required): $300–$560
- Design and drafting: $3,000–$8,000 depending on complexity
- Temporary accommodation if you need to move out during construction
Hidden Costs That Catch Homeowners Out
If you need to rent while your extension is being built, this could add $4,000 to over $8,500 to your total project cost,based on typical rental periods and Launceston’s rental market.
Then there are the finishing touches that everyone forgets about – new window treatments, landscaping repairs, extending your heating system, and matching existing finishes. Set aside 10-20% of your construction budget as a contingency for unexpected issues, such as discovering structural problems or needing to upgrade electrical systems to meet current codes.
Why Extension Costs Have Changed in 2025
Building construction cost increased by 3.4% in 2024, marking the largest annual rise since September 2023, according to CoreLogic’s Construction Cost Index. Annual growth in output prices for other residential building construction and non-residential building construction has continued to trend above 5% in 2024, as rising labour and project costs were passed on.
The Australian Bureau of Statistics data shows that construction costs have risen significantly. From September 2020 to June 2024, prices received by building construction businesses increased 31.1%, driven by growth in house construction prices which rose 40.8% over this period Australian Bureau of Statistics.
But here’s the flip side: the average Launceston home has increased significantly in value over the past few years. A well-executed extension typically adds 10-15% to your property value, making it both a lifestyle improvement and a solid financial investment.
Ready to Plan Your Extension?
Understanding how much to extend a house in Tasmania is the first step. The next is working with builders who know Launceston’s unique requirements, from council approvals to Tasmania’s climate considerations.
At Go Build Co, we’ve helped dozens of Launceston homeowners navigate the extension process, from initial concepts through to final completion. We provide transparent pricing, manage all permits, and deliver quality house extensions that add real value to your home.
Get in touch for an obligation-free consultation about your extension project. We’ll walk you through realistic costs, timelines, and what’s actually achievable with your budget.
