Home Extension Melbourne: Expert Builders, Custom Designs & Fixed Prices

Why Melbourne Homeowners Choose a Home Extension

With Melbourne’s property prices continuing to climb, extending your existing home is often far more cost-effective than upsizing to a bigger property. A well-designed home extension in Melbourne adds livable square metres, improves daily comfort, and can significantly boost your property’s resale value — all without the stress of moving.

Whether you need an extra bedroom for a growing family, a larger open-plan living area, a dedicated home office, or an alfresco entertaining space, 5J Building Group delivers home extension projects that are seamlessly integrated with your existing home.

More Space Without the Moving Costs

Stamp duty, agent fees, and removal costs add up fast. A home extension lets you stay in the suburb you love while getting the space you need — at a fraction of the cost of buying elsewhere in Melbourne.

Add Real Value to Your Melbourne Property

A professionally built home extension can increase your property’s market value by up to 20–30%, making it one of the highest-return home improvement investments available to Melbourne homeowners.

Ready to extend your Melbourne home?Get a free design consultation with 5J Building Group — Melbourne’s trusted home extension specialists.

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Types of Home Extensions We Build in Melbourne

Every home is different, and every family has unique needs. 5J Building Group specialises in a wide range of home extension types across Melbourne’s inner, middle, and outer suburbs.

Rear Home Extensions

The most common type of home extension in Melbourne. We extend the back of your home to create a larger kitchen, dining room, living area, or master suite — all flowing seamlessly onto your outdoor space.

Side Return Extensions

Make the most of the unused strip of land alongside your home. A side return extension widens your ground floor to create a more open, airy layout — perfect for terrace and semi-detached homes.

Second Storey Additions

When your block size limits ground-floor expansion, building up is the answer. Our second storey additions in Melbourne are structurally sound, architecturally considered, and designed to match your home’s existing character.

Wraparound Extensions

Combining rear and side extensions for maximum impact, wraparound extensions deliver a substantial increase in living space and are ideal for homeowners looking for a full transformation.

Granny Flats & Dual Occupancy

Looking to add an independent living space for family or as an investment? Our Melbourne granny flat and dual occupancy extensions are fully self-contained and built to meet all council requirements.

The 5J Building Group Home Extension Process

We’ve refined our end-to-end process to make your home extension in Melbourne as smooth and stress-free as possible. From the first conversation to the final walkthrough, you’ll always know exactly where your project stands.

Step 1: Free Design Consultation

Our in-house design consultants meet with you to understand your vision, your lifestyle, and your budget. This service is completely free. We bring ideas, you bring the dream — and together we map out exactly what your extension will look like.

Step 2: Detailed Working Drawings

Once the design is agreed upon, our drafters produce precise working drawings that meet all Victorian building standards. These drawings form the technical blueprint your construction team will follow to the millimetre.

Step 3: Plans, Permits & Council Approvals

We handle every permit, report, and council application on your behalf. Whether your project requires a building permit, soil report, or BAL (Bushfire Attack Level) assessment, our team manages the entire regulatory process so you don’t have to.

Step 4: Fixed-Price Contract & Construction

Before a single brick is laid, you receive a clear, fixed-price contract. No hidden costs. No surprises. Construction begins on schedule, with daily updates and a dedicated site supervisor ensuring quality at every stage.

Step 5: Handover & Aftercare

Once your home extension is complete, we conduct a thorough walkthrough with you to ensure every detail is perfect. Our aftercare commitment means any issues identified post-handover are resolved promptly.

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Why Choose 5J Building Group for Your Melbourne Home Extension?

With dozens of building companies operating across Melbourne, choosing the right partner for your home extension is one of the most important decisions you’ll make. Here’s why Melbourne homeowners trust 5J Building Group.

Registered Domestic Builder (Unlimited) — CDB-U 73492

We hold an Unlimited Domestic Builder licence issued under the Victorian Building Authority (VBA). This means we’re fully qualified and insured to manage residential projects of any size, giving you complete peace of mind.

Complete In-House Team — No Subcontracting Chaos

Unlike many competitors, 5J Building Group operates with a fully integrated in-house team covering design, drafting, permits, and construction. You deal with one company, one contact, and one fixed price from start to finish.

Transparent, Fixed-Price Contracts

We don’t do surprise invoices. Every client receives a detailed fixed-price contract before work commences, so you know exactly what you’re paying — no hidden fees, no scope creep, no stress.

5-Star Reviews on Word of Mouth

Our reputation is built on results. Hundreds of Melbourne homeowners have rated 5J Building Group five stars on Word of Mouth, consistently praising our craftsmanship, communication, and punctuality.

On-Time, Every Time

We provide a clear project timeline before construction begins and arrive on site every scheduled day. If an unexpected challenge arises, you’ll be informed immediately — not after the fact.

Home Extension Melbourne Cost: What to Expect

One of the most common questions we receive is: how much does a home extension cost in Melbourne? The honest answer is that every project is different — but we believe in full transparency, so here’s a general guide.

Extension Type	Approx. Size	Estimated Cost Range
Small Rear Extension	20–40 sqm	$80,000 – $150,000
Mid-Size Rear Extension	40–80 sqm	$150,000 – $280,000
Large Rear / Wraparound	80–120 sqm	$280,000 – $450,000+
Second Storey Addition	60–120 sqm	$200,000 – $400,000+
Granny Flat	40–60 sqm	$120,000 – $200,000

Note: Costs are indicative for Melbourne metro projects in 2025–2026 and vary based on design complexity, materials, site conditions, and council requirements. Contact us for a free, accurate quote.

Home Extension Projects – Customer Reviews

Home Extension Melbourne: Areas We Serve

5J Building Group delivers home extensions across Greater Melbourne, with particular expertise in the inner and middle ring suburbs. Our offices in Brighton and Toorak place us at the heart of Melbourne’s most sought-after residential precincts.

Inner Melbourne Suburbs

Brighton, Toorak, South Yarra, St Kilda, Prahran, Richmond, Fitzroy, Carlton, Northcote, Hawthorn, Camberwell, Glen Waverley, Box Hill, and surrounds.

Western & Northern Suburbs

Williamstown, Footscray, Brunswick, Coburg, Essendon, Moonee Ponds, Ascot Vale, and nearby areas.

Eastern & South-Eastern Suburbs

Malvern, Caulfield, Elsternwick, Oakleigh, Mount Waverley, Doncaster, Templestowe, and surrounding suburbs.

Frequently Asked Questions — Home Extension Melbourne

Do I need a building permit for a home extension in Melbourne?

In most cases, yes. Any structural extension in Victoria will require a building permit issued through a registered building surveyor. Our team handles the entire permit process on your behalf, including liaising with your local council.

How long does a home extension take in Melbourne?

A small rear extension typically takes 10–16 weeks from construction commencement. Larger projects, second storey additions, or those requiring significant structural work may take 20–32 weeks. The design, drawing, and permit phase typically adds a further 6–12 weeks before construction begins.

Can I live in my home during the extension?

In most cases, yes — especially for rear extensions and additions. We work methodically to minimise disruption to your daily routine and take every precaution to keep your home clean, secure, and liveable throughout the build.

What is the difference between a home extension and a renovation?

A renovation modifies your existing space — updating kitchens, bathrooms, or layouts. A home extension adds new, additional floor space to your property. Many of our projects combine both: we extend the home and renovate the existing interior at the same time.

How do I get started with 5J Building Group?

Simply call us on 03 9886 3731 or 0424 883 173, or send an enquiry via our contact page. We’ll arrange a free, no-obligation design consultation at your home at a time that suits you.

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