How Much Does A Home Extension Cost?

What’s the Average Cost of House Extensions in Australia? Per m² Pricing Explained

What is the average cost per square metre to build a house extension in Australia, including single-storey and second-storey additions?

House extensions cost in Australia typically range from $2,000/m² to $4,000/m², depending on the design, materials, and complexity of the build. For example, an 80m² ground floor extension can cost between $160,000 and $320,000 based on national averages. Understanding these costs helps homeowners budget accurately and avoid unexpected renovation expenses.

Home extensions have become an increasingly popular solution for Australian homeowners seeking to expand their living spaces without the hassle of moving. Whether you need an extra bedroom, a larger kitchen, or a home office, extensions offer a versatile and cost-effective way to enhance your property. But how much does a home extension cost? The answer depends on various factors like the type of extension, its size, the materials used, and even the location of your home.

If you're wondering how much to extend a house in Australia, you’ll find that costs vary widely depending on your specific project. The extension house cost for a basic design may start around $50,000, while more complex or high-end builds can exceed $100,000.

For those in Victoria, house extension costs in Melbourne tend to reflect urban demand and higher living expenses. Whether you're considering a single-storey build or looking into the cost to build an upstairs extension, Melbourne homeowners should budget carefully, as prices can climb with architectural complexity and premium finishes.

Adding a second level? You’re likely asking, How much does a second story extension cost? First-floor or double-storey additions are more expensive due to structural reinforcements and access issues. The average first floor extension cost can start around $100,000 and go much higher based on size and inclusions.

If your plans include a new kitchen or bathroom, keep in mind that these specialized spaces tend to cost more. The cost of a kitchen extension can range from $20,000 to $50,000, depending on the fittings and layout, while an ensuite extension cost may start from $15,000 and scale up, depending on the plumbing and fixtures.

To make the planning process easier, consider using an extension cost calculator to estimate expenses based on your specifications. These tools can provide a helpful starting point, whether you’re budgeting for a full renovation or just adding a few meters of space.

In fast-growing urban areas, extensions aren't just about more room, they're about smarter living. A well-planned extension improves comfort, increases property value, and adapts your home to your lifestyle. Whether you're creating a playroom, a quiet office, or extra storage, understanding your extension cost in Melbourne or elsewhere in Australia is key to making informed decisions.

No matter your goals, getting clear on extension house costs will set the stage for a successful and stress-free renovation.

Common Reasons That A Building Needs An Extension

• Creating More Space- The addition in the number of family members in a growing family is a common scenario where people tend to create more spaces for dining areas, kitchen areas, etc.


• Increasing Property Value- With house extensions in a well-designed manner, you can add value to your property and make it more attractive while enhancing its aesthetics and functionality.
  


• Improving Accessibility- If you are a family that has an individual with any kind of mobility challenges, then extensions can be done to improve the accessibility for that individual. Your extensions mainly include features like a ramp and ground flooring bathrooms for easy access.


• Increase Natural Light- An easy way to increase the natural light indoors is to incorporate modern skylights, open-plan designs, and windows.


• Accommodating Multigenerational Living- To accommodate multiple generations in a place together, a few families start house extensions by providing different spaces based on generation requirements.


• Designing A Master Suite- A choice of extending your house with a master bedroom suite that has an attached walk-in closet and bathroom enhances your indoors.


• Modernising And Upgrading- If the only goal is to update and modernise your house, then incorporate it with energy-efficient features, advanced technology, and contemporary design elements.

How Much Does A Home Extension Cost

With a budget home extension plan in mind, people are often concerned about how much a home extension costs on average. For a house extension at ground level, it takes approximately $1,500 to $4,000 per square yard or m². However, if you want to know the cost allocation based on the quality, it is different.

• Basic Quality- $1,500 to $2,500 per square metre.


• Medium Quality- $2,500 to $3,000 per square metre.


• High Quality- $3,000 to $4,000 per square metre.

So, based on these numbers, you can calculate the cost of a 50 m2 extension. If you calculate the house extension cost for 80m², then the cost would be around.

• Basic Quality- $120,000 to $200,000 per square metre.


• Medium Quality- $200,000 to $240,000 per square metre.


• High Quality- $240,000 to $320,000 per square metre.

The cost for a second-house extension would be 50% more than the usual ground-floor extension the considering quality. The detailed cost factors and numbers for a house extension will be discussed further. So, if you are worried about such details, do look for the details we mentioned here.

House Extension Cost Per m² In Australia

If you're curious about the exact costs of house extensions in Australia, here's what you need to know. The cost of extensions can vary significantly depending on the quality of materials and the complexity of the project. On average, house extensions fall within a general range, but specific pricing will depend on your unique needs. Local carpenters are essential in ensuring your extension project is completed with precision and quality. Connect with skilled carpenters and home builders who can help bring your extension vision to life. On average, home extensions cost per m2 for different additions are:

• $1350/m2 for a timber ground floor extension.


• $1500/m2 for a brick veneer ground floor extension.


• $2100/m2 for a first-floor extension.


• $1,500 to $4,000 per square yard for a ground floor extension.


• $2,500 to $3,500 per square yard for a second-floor extension.

Based on these floor-wise extension costs, it takes between $120,000 and $320,000 for an 80m² ground floor house extension. At the same time, it roughly takes between $90,000 and $240,000 for a 60m² based on the quality factor. So, you can save around $30,000 to $80,000 for a 60 m² extension.

Key Factors That Impact the Cost Of A Home Extension

Are you confused about "how much should a house extension cost”? Several factors can directly impact the house extension cost, and it is crucial to understand them before you plan for an extension. Here are some key factors that need to be considered in the house extension costs.

• Quality of the materials- Basic, medium, and high.


• Size and scope of the extension- Large, medium, and small.


• Architectural design- Based on client requirements and choice.


• Location- Rural and urban areas.


• Site conditions- Poor soil, excavation, difficult terrain, etc.


• Labour costs- Depends upon some of the major aspects like skills, location, demand for construction services, and the project type.


• Utilities and services- Includes electrical, plumbing, and HVAC units in addition to relocation of gas lines.


• Time of the year- Costs of material and labour vary depending on the building season.


• Interior finishing- Your choice of cabinets, flooring, light fixtures, countertops, and other high-end finishes.


• Consistency- A consistency fund that will be used in case of unexpected changes in the overall project.


• Economic factors- Inflation and construction market fluctuations can dramatically impact the cost of labour and materials.


• Project management- Hiring an architect or a certified project manager.


• Permits and regulations- Local building regulations such as planning permits, building permits, and environmental permits. Compliance with zoning regulations, setback requirements, and following historic preservation guidelines.

Average Hourly Labour Cost For House Extension In Australia

As experts charge a flat rate or hourly rates in case of house extensions, there is an impact on the overall cost of house renovations in different states of Australia. Costs associated with a home extension change depending on the location of the state and the hourly labour rates. The labour prices in Australian cities are as follows:

• Labour Rates In Melbourne- $45 per hour


• Labour Rates In Brisbane- $45 per hour


• Labour Rates In Sydney- $40 per hour


• Labour Rates In Perth- $45 per hour


• Labour Rates In Adelaide- $50 per hour


• Labour Rates In Canberra- $50 per hour

Other Costs To Consider While Budgeting For Home Extension

A house extension quote usually accounts in favour of windows, doors, insulation, roofs, ceilings, interiors, and other exteriors. But some of them are missing your considerations, which usually need to be included in the budget too. So, for a complete analysis of “how much does a home extension cost”, you must consider these options related to home extensions.

• Lighting fixtures


• Furniture and furnishings


• Appliances


• Equipment


• HVAC units


• Built-in storage


• Technology and wiring


• Utility connection


• Cleaning and final touches


• Permit fees and inspections.

Price List Of Different Types Of Home Extensions

By considering the size, shape, location, quality, complexity, and some other specific features, approximate cost ranges for different house extensions are stated here. Therefore, take a look at how each of the house extensions is caused based on the mentioned factors above.

• Kitchen Extension: $20,000 to $50,000


• Bathroom Extension: $15,000 to $40,000


• Garage Conversion: $15,000 to $30,000


• Porch Extension: $15,000 to $25,000


• Wrap-Around Extension: $30,000 to $40,000


• Conservatory Extension: $5,000 to $30,000
• Loft conversion: $2,500 to $30,000
  

Now, how much does a home extension cost must be clear to you.

How You Can Save Your House Extension Costs From Exceeding

In fact, besides all this, you can even save your pockets from additional investments by smart decision-making, careful planning, gaining access to skilled labour, practising local building practices, etc. Strategies you can incorporate for the above are,

• Setting a realistic budget


• Prioritising and planning


• Efficient designing


• Reusing the existing space


• Competitive building


• Reusing the materials


• Negotiate with the contractors


• Energy-efficient upgrades


• Bulk purchases


• Research local incentives

Two Case Studies Submitted By Home Extension Experts

Case Study 1: Adding 40 m² Extension

Location: Sydney, New South Wales

Client: Sarah and James Thompson

Need: They wanted to add an extension of 40 m² to their existing home with energy-efficient features and contemporary design elements.

• Extension Type: Ground floor extension


• Quality: High quality


• Budget: $20,000

40 m² Extension Cost Key Factors:

Design: Single room with energy-efficient and modern design features.

Materials: Wood and Iron

Interior Finishing: Premium finishing with two cabinets

Challenges:

Site Conditions: No excavation was required, but the attachment creation was a big issue.

Ventilation Feature: Added ventilation from two sides and a small window for energy efficiency.

Final Result:

The extension was built with no damage to the surroundings and all features demanded by the family. The space was enough for the accommodation of the new member in the house, and they were happy with the work. 

Case Study 2: 60m² House Extension

Location: Brisbane, Queensland

Client: The Patel Family

Home Extension Scene: The demand was to create a multigenerational living space of 60 m² to accommodate grandparents who would provide separate living quarters. 

• Type: Ground floor extension


• Quality: Medium quality


• Budget: $28,000

Cost Influencing Reasons:

Project Scope: 60 m² was a larger extension.

Materials: Timber and Iron

Challenges:

Local Regulation: Brisbane has local regulations called the Dwelling House Code for creating home extensions. We got permission with some explanations. 

Interior Finishing: We had to meet budget constraints, so the interior finishing was very simple, but all with agreement from the client.

Family Reaction:

The home extension was created as they wanted. They were happy to have a separate living space for their parents. The work was cost-effective and pleasing as they were able to save $2000 from the given budget. 

Choose Home Extension Experts At ServiceTasker

 Your local home extension experts are not far from you, since you can find many of them on ServiceTasker. Post your task, receive FREE quotes from certified local home extension experts, and connect with verified contractors to choose the one suitable for your needs. 

As you plan your home extension, safety is paramount, especially with electrical installations. Familiarize yourself with essential electrical safety tips for your home to ensure a secure environment for your family in the extended space.