Building Extensions Melbourne: Your Complete Guide

Melbourne homeowners are increasingly choosing building extensions to expand their living space without relocating. These projects offer significant value while avoiding the stress of moving house.

We at Cameron Construction understand that planning building extensions Melbourne requires careful consideration of permits, costs, and design options. This guide covers everything you need to know about extending your Melbourne home successfully.

What Extension Type Best Suits Your Melbourne Home

Double Storey Extensions Transform Living Space

Double storey extensions deliver the highest return on investment for Melbourne homeowners, typically adding 15-20% to property value according to Victorian property data. These extensions work exceptionally well on narrow lots where ground space is limited but height restrictions allow additional levels.

Most Melbourne councils permit building heights up to 10 metres, with some areas allowing 10 metres on sloping sites. Double storey additions cost approximately $3,500-$4,500 per square metre but provide twice the floor area of single-storey alternatives.

The key advantage lies in maximising space without sacrificing outdoor areas. This makes them ideal for families who need bedrooms, bathrooms, and living zones while maintaining garden space for children and entertainment.

Ground Floor Extensions Suit Heritage and Character Homes

Ground floor extensions work best for heritage properties where second storey additions face strict council restrictions. These extensions typically cost $2,800-$3,800 per square metre and integrate seamlessly with existing rooflines.

Melbourne’s heritage overlay areas (including Richmond, Fitzroy, and South Yarra) often require ground-level solutions to preserve streetscape character. Side and rear setback requirements limit extension size to 60% site coverage maximum, but skilled design maximises usable space.

Kitchen and bathroom renovations within ground floor extensions show strong resale appeal, with modern kitchens adding $25,000-$35,000 to property value.

Second Storey Additions Maximise Existing Footprints

Second storey additions suit homes with solid foundations and adequate structural capacity, costing $3,200-$4,200 per square metre. These conversions work well on flat sites where double storey construction proves challenging due to council height limits or neighbour objections.

Structural engineers assess foundation capacity before design begins, as older Melbourne homes may require reinforcement. The process involves removing existing roof structures and building upward from strengthened walls.

Understanding these extension types helps you choose the right approach for your property and budget. The next step involves navigating Melbourne’s complex planning and permit requirements to turn your extension vision into reality.

What Permits Do Melbourne Extensions Need

Melbourne’s planning system requires both planning permits and building permits for most extension projects, with council requirements that vary significantly across the 31 local government areas. Inner Melbourne councils like Yarra and Port Phillip enforce stricter heritage overlays and setback requirements, while outer councils focus primarily on standard residential zones. Planning permits cost between $1,500-$3,500 (depending on project complexity and council fees), with processing times that average 6-8 weeks for straightforward applications.

Council Requirements Vary Across Melbourne Zones

Each Melbourne council applies different interpretations of state planning policies, which creates substantial variation in approval requirements. Bayside Council requires 3-metre rear setbacks for extensions over $50,000, while Boroondara Council permits 2-metre setbacks in similar circumstances. Heritage overlay areas cover approximately 40% of inner Melbourne properties and face additional design restrictions that can add 4-6 weeks to approval timeframes. Councils assess neighbourhood character, overlooking impacts, and building bulk against local planning schemes that change regularly through council amendments.

Building Permits Follow State-Wide Standards

Building permits cost 0.128% of construction value with minimum fees of $162 according to Victorian Building Authority guidelines. Registered building surveyors issue these permits after planning approval and require detailed construction drawings that meet National Construction Code standards. Extensions over 10 square metres always require building permits, with inspections that occur at foundation, frame, waterproof membrane, and final completion stages. Private building surveyors typically process applications 2-3 weeks faster than council building departments, though fees increase by approximately 20-30%.

Town Planning Considerations Shape Extension Design

Site coverage limits restrict extensions to 60% of total land area, while building heights face 9-metre limits in standard residential zones. Overlooking provisions require screening for windows within 9 metres of neighbouring boundaries, which often necessitates highlight windows or obscure glazing solutions. Private open space requirements mandate minimum 40 square metres of usable outdoor area and force careful design balance between extension size and garden retention. These constraints directly impact extension feasibility and guide initial design discussions before architect engagement.

Understanding permit requirements helps you plan realistic timelines and budgets for your extension project. The next consideration involves calculating actual construction costs and establishing a comprehensive budget that accounts for all project phases.

What Do Melbourne Extensions Actually Cost

Melbourne extension costs depend heavily on construction complexity, finishes quality, and site access challenges. Double storey extensions range from $3,500-$4,500 per square metre, while ground floor additions cost $2,800-$3,800 per square metre according to Master Builders Victoria data from 2024. Premium finishes and structural modifications increase costs by 20-30%, while difficult access sites add $200-$400 per square metre for crane hire and material handling.

Kitchen and Bathroom Inclusions Drive Premium Costs

Kitchen and bathroom inclusions within extensions command premium rates, with quality kitchen fit-outs that add $35,000-$50,000 to base construction costs. Modern bathroom installations contribute $15,000-$25,000 to project totals, particularly when they include premium fixtures and waterproofing systems. Site preparation work varies dramatically, from $5,000 for simple excavation to $25,000 for complex retaining walls on sloping blocks (especially common in Melbourne’s hilly eastern suburbs).

Design Phase Requires Three to Six Months

Professional design development requires 12-16 weeks from initial consultation to permit-ready drawings, with architectural fees that range from 8-12% of total construction value. Structural engineers charge $3,500-$6,500 for double storey projects, while energy efficiency assessments cost $800-$1,200 under National Construction Code requirements. Planning permit applications extend timelines by 6-10 weeks depending on council processing speeds, with heritage overlay properties that face additional 4-6 week delays.

Construction Timeframes Follow Permit Approval

Construction commencement follows 2-4 weeks after permit approval, which makes total project timelines 6-9 months from design start to completion. Weather delays during Melbourne’s winter months can extend construction by 2-3 weeks, particularly for roofing and external work phases. Quality builders schedule inspections at foundation, frame, waterproof membrane, and completion stages to meet Victorian Building Authority requirements.

Smart Investment Strategies Maximise Property Returns

Double storey extensions provide significant property value increases, while single-storey additions typically achieve 10-15% gains according to Victorian property market analysis. Location significantly impacts returns, with inner Melbourne properties that achieve higher percentage gains than outer suburban areas. Strategic extension design that creates additional bedrooms and living zones appeals to growing families and maximises rental potential for investment properties.

Final Thoughts

Professional extension builders deliver superior outcomes through comprehensive project management, technical expertise, and established council relationships. Melbourne’s complex planning environment requires builders who understand local regulations, heritage overlays, and neighbourhood character assessments that vary significantly across the 31 council areas. Experienced builders coordinate architects, engineers, and surveyors while they manage permit applications, inspections, and compliance requirements.

This integrated approach reduces project delays and cost overruns that commonly affect DIY or inexperienced contractor projects. Quality builders provide fixed-price contracts, detailed project timelines, and warranty protection that safeguards your investment throughout construction and beyond. Your next step involves selection of a builder with proven Melbourne experience and comprehensive service delivery.

We at Cameron Construction specialise in building extensions Melbourne with extensive experience in double storey extensions, ground floor additions, and second storey conversions. Our in-house team handles concept to completion (including planning, permits, and BCA compliance across Melbourne’s councils). Contact us today to discuss how we can transform your home with professional extension services.