As family needs evolve, many Melbourne homeowners find themselves pressed for space. However, high stamp duty costs, real estate fees, and a desire to remain close to local schools and community networks make moving houses an unattractive option. A second-storey addition allows you to double your floor area, add extra bedrooms, or create a private parents' retreat without sacrificing a single square metre of your backyard.
Building upwards in Metropolitan Melbourne involves navigating unique structural challenges, engineering load requirements, and council planning overlays such as height restrictions and boundary setbacks. Selecting a specialist builder who handles structural assessments, architectural drafting, council permits, and construction under a single contract is crucial. To assist you in evaluating your options, we have compiled a non-ranked guide to ten verified second-storey addition specialists operating across Melbourne.
1. Yorcon
Location: Servicing Metro Melbourne (Inner North, East, Bayside & Suburbs)
Website: yorcon.com.au
Core Services: Custom second-storey additions, vertical home extensions, architectural design and construct, structural engineering management, and total project management.
Pricing: Not publicly listed.
Why Consider Them:
Yorcon stands out as a leading custom builder and home extension specialist in Melbourne, backed by nearly two decades of residential construction experience. Specialising in seamless design-and-construct partnerships, Yorcon transforms single-storey properties into spacious double-storey family homes without losing architectural cohesion.
Whether extending a period weatherboard in Thornbury, a brick residence in Ivanhoe, or a coastal home in Bayside, Yorcon manages every stage of the upper-level build. Their team conducts thorough preliminary structural assessments to check footing and wall load capabilities before drafting plans. By coordinating local council planning approvals, engineering specifications, and construction internally, Yorcon eliminates miscommunication between architects and trades. For property owners seeking a direct, highly personalised relationship with a master builder who delivers custom finishes within agreed timeframes, Yorcon represents a top-tier local provider to consult.
2. Mass Constructions
Location: Servicing Inner South-East Melbourne & Bayside
Website: massconstructions.com.au
Core Services: Second-storey additions, upper-floor master suites, structural alterations, ground-to-upper floor integrations, and fixed-price contracts.
Pricing: Not publicly listed.
Why Consider Them:
Mass Constructions is a dedicated residential renovation and extension specialist with over 50 years of combined trade experience across Melbourne’s inner south-eastern suburbs. They focus heavily on upper-level additions, helping families build upwards to unlock extra living zones, bathrooms, and bedrooms. Using an online client portal, Mass Constructions provides real-time progress updates and transparent communication throughout the structural phase, making them a structured option for homeowners who want clear visibility during their build.
3. Spacemaker Home Extensions
Location: Unit 1, 173-181 Rooks Road, Vermont VIC 3133
Website: spacemaker.com.au
Core Services: Second-storey house extensions, architectural drafting, council planning assistance, and custom home transformations.
Pricing: Not publicly listed.
Why Consider Them:
Operating in Melbourne for over 50 years, Spacemaker Home Extensions is a multi-award-winning builder known for executing complex vertical builds. Their six-step design-to-completion process ensures that upper-floor additions match the original architecture of the home, whether modern or heritage. Spacemaker is a strong candidate to evaluate if you require end-to-end guidance from initial concept drafting through to council planning permits.
4. Extension Factory
Location: Suite 29, Paragon Building, 799 Springvale Road, Mulgrave VIC 3170
Website: extensionfactory.com.au
Core Services: Second-storey additions, single-storey extensions, structural home renovations, and fixed-price building contracts.
Pricing: Not publicly listed.
Why Consider Them:
With operational experience dating back to 1979, Extension Factory is one of Melbourne’s largest and most established extension specialists. Having completed thousands of home transformations across suburban Melbourne, they provide fixed-price quotes and structured extended warranty coverage. They are a well-known option for homeowners seeking a large, experienced company capable of managing full-scale vertical additions.
5. Duncan Thompson Extensions
Location: 892 Riversdale Rd, Camberwell VIC 3124
Website: duncanthompson.com.au
Core Services: Boutique second-storey additions, period and heritage home extensions, custom architectural design, and construction management.
Pricing: Not publicly listed.
Why Consider Them:
Based in Camberwell, Duncan Thompson Extensions brings more than 30 years of specialized experience to residential extension projects across Melbourne’s eastern and Bayside suburbs. They excel at designing second-storey extensions for character homes—such as Victorian weatherboards and Californian bungalows—ensuring the new upper level integrates smoothly with the original roofline and facade.
6. Supa Group Extensions
Location: 63 Northern Road, Heidelberg West VIC 3081
Website: supagroup.com.au
Core Services: Second-storey additions, ground-floor expansions, 3D concept design, council permit administration, and fixed-price contracts.
Pricing: Not publicly listed.
Why Consider Them:
Supa Group Extensions has served Metropolitan Melbourne for over 50 years, specializing in both ground-floor and vertical house extensions. Their single-team approach coordinates initial 3D design walkthroughs, structural assessments, council submissions, and construction. Supa Group is a reliable provider to compare if you want a guaranteed start date and structured timeline milestones.
7. XL Built
Location: Servicing Metropolitan Melbourne
Website: xlbuilt.com.au
Core Services: Custom second-floor extensions, partial upper additions, parent retreat builds, and full site assessment services.
Pricing: Not publicly listed.
Why Consider Them:
XL Built is a third-generation building company with over 45 years of residential extension experience in Victoria. They focus on tailored second-storey floor plans designed around family lifestyle requirements, such as adding master suites, extra bedrooms, or home office zones. XL Built provides detailed site scoping to anticipate structural reinforcement costs before construction starts.
8. Prime Builders
Location: 135 Bamfield Rd, Heidelberg VIC 3081
Website: primebuilders.com.au
Core Services: Double-storey builds, second-storey additions to existing homes, structural footing assessments, and custom renovations.
Pricing: Not publicly listed.
Why Consider Them:
Operating from Heidelberg, Prime Builders specialises in custom double-storey construction and vertical home additions across Melbourne. They place strong emphasis on pre-construction structural auditing, assessing existing wall frames, timber joists, and concrete footings to ensure upper levels are safely supported. They represent a practical local choice for homeowners with narrow or complex blocks.
9. Mardo Building Co.
Location: Servicing Metro Melbourne
Website: mardobuildingco.com.au
Core Services: Second-storey additions, upper-level expansions, structural integrity assessments, and council planning permit management.
Pricing: Not publicly listed.
Why Consider Them:
Mardo Building Co. is a licensed Melbourne building firm focused on delivering fully managed upper-level extensions. They provide fixed-price quotes paired with a 10-year workmanship warranty, offering peace of mind to growing families. Their team manages the complete approvals process, including soil testing, engineering calculations, and council submissions.
10. Elevate Building Group
Location: Servicing Northern, Eastern & Inner Melbourne Suburbs
Website: elevatebuilding.com.au
Core Services: Full second-storey additions, partial upper-floor extensions, structural engineering assessments, and custom home renovations.
Pricing: Not publicly listed.
Why Consider Them:
Elevate Building Group brings over 40 years of combined industry experience to second-storey extensions across Melbourne’s northern and eastern suburbs, including Northcote, Kew, Hawthorn, and Ivanhoe. They focus on blending the new second level seamlessly with the ground floor, paying close attention to stairwell placement, window proportions, and natural light optimization.
Key Steps When Planning a Second-Storey Addition in Melbourne
Before commencing an upper-floor addition, keep these critical project stages in mind:
Verify Structural Footings & Frame: A second storey adds significant weight to your existing ground-floor structure. Ensure your builder conducts a structural assessment of your foundations, stumps, and load-bearing walls before finalizing designs.
Review Council Height Limits & Overlooking: Melbourne councils enforce strict ResCode regulations regarding building heights, overshadowing neighbouring properties, and window privacy screening.
Plan for Temporary Accommodation: Removing a roof to add a second storey temporarily exposes the ground floor to the elements. Most families choose to move out during the framing and roofing stage for safety and comfort.
Select an Integrated Builder: Choosing a builder who manages design, engineering approvals, and trade construction under one contract minimizes delays and protects your budget.
