Build costs, approval fees and designer fees in one place. Based on 2025-26 Australian market rates.
Indicative guide. Always get at least 3 builder quotes before committing.
What are you building?
Home extension
Granny flat
New home
Knockdown rebuild
Renovation
Deck / pergola
Garage / shed
Pool
Pool type
Fibreglass in-ground
Concrete in-ground
Plunge pool
Above ground
Why pool costs vary so much
Fibreglass: fast install, fixed shapes, lower cost. Concrete: fully custom, higher cost, longer build. Plunge pools: compact, good for small blocks. Above ground: no excavation, lowest cost but limited longevity. Fencing, heating, pumps and landscaping are always extra.
Size of new space
80m²
20m²300m²
Location
Newcastle / Hunter
Regional NSW
Sydney
Melbourne
Regional VIC
Brisbane
Perth
Adelaide
Finish level
Budget
Mid-range
High-end
Architectural
Quality construction, modern fittings, good insulation, standard inclusions. The most common choice for owner-occupiers.
Site conditions
Sloping block
Extra excavation, retaining walls, engineering
Adds $15,000 to $45,000 depending on slope
Difficult site access
Narrow lane, crane required, inner-city block
Adds $8,000 to $20,000
Demolition required
Removing existing structure before building
Adds $15,000 to $35,000
Asbestos present (pre-1990 home)
Licensed removal required before any work
Adds $3,000 to $15,000 depending on extent
Approval fees (what you pay the government and certifiers)
Note on approval fees
These are separate from build costs. Approval fees are paid to the certifier, council, or state government regardless of which builder you use. They are largely fixed and non-negotiable.
Designer and architect fees
Why designer fees vary so widely
Volume builders include design in their package. A draftsperson charges per drawing set. A building designer handles more complex projects. A Masters-qualified designer typically charges a percentage of the build cost for full service (concept through to construction). For projects over $300k, an architect's involvement often saves money by avoiding costly design errors and managing the build properly.
Hidden costs most people forget
Rates based on HIA, Rawlinsons Construction Cost Guide, BMT QS, Altus Group and industry data (2025-26).
Updated April 2026. Costs exclude GST unless noted. Always obtain written quotes.
Total project estimate
$320,000 to $420,000 80m² extension, mid-range, Hunter region