Concrete Slab Cost Sydney 2026: Every Project Type

Concrete slab costs in Sydney usually range from $75–175/m² in 2026. A house slab is typically $10,000–28,000, a garage slab $3,200–10,000, and a patio $2,800–9,000 before site-specific engineering, access, and finish upgrades.

Foucauld Dalle, Founder of MixHubUpdated 30 April 2026

Concrete Slab Costs by Project Type: Sydney 2026

Quick answer: most Sydney slabs cost $75–175/m² installed. Use N25 concrete (25 MPa) for many residential ground slabs, N32 concrete (32 MPa) where the engineer specifies higher strength, and calculate cubic metres before comparing delivered concrete prices.

Project typeTypical areaConcrete m³Total installed costCost per m²
House slab (raft)80–150m²12–22m³$10,000–28,000$100–175/m²
Garage floor (single)30–40m²3–4m³$3,200–6,000$90–145/m²
Garage floor (double)50–65m²5–7m³$5,000–10,000$85–135/m²
Alfresco / patio20–50m²2–6m³$2,800–9,000$80–160/m²
Shed floor15–30m²1.5–3.5m³$1,800–4,500$75–120/m²
Concrete path (1m wide)Per metre0.1–0.15m³/lm$130–220/lm$130–220/m²

Calculate volume before you price the slab

Enter your slab dimensions to estimate cubic metres, bag equivalents, and Sydney delivered pricing before you request a quote.

Postcode and delivery date route you to available local plants.

House Slab Cost Sydney

A house slab (also called a raft slab or slab-on-ground) is the most complex concrete pour a homeowner typically encounters. It requires a structural engineer specification and is closely tied to soil classification (A, S, M, H1, H2, E, P) which dramatically affects the design and cost.

Worked Example: 120m² House Slab, Campbelltown (M-class soil)

ItemCost
Geotech report$800
Structural engineer design$1,200
Formwork and edge boards$2,400
DGB20 base (100mm) + compaction$2,400
DPM (200µm)$600
Reinforcement (N25 steel, M-class)$3,600
Ready-mix concrete (N25, 15m³ + pump)$5,100–5,550 + $800 pump
Labour (pour + finish)$3,600
Contractor margin (15%)$2,975
Total (~$190/m²)$23,025

Note: M-class (moderately reactive) soil is common in Campbelltown and western Sydney. H1 or H2 classification can add $3,000–8,000 to the slab cost through additional reo and thicker design.

Garage Floor Slab Cost Sydney

Garage floor slabs are simpler than house slabs: no engineer report required for detached garages on stable ground, no DPM mandatory (though recommended), and typically N25 is sufficient for domestic vehicles.

Garage typeSizeTotal cost (installed)
Single (6m × 6m)36m²$3,500–6,500
Double (6m × 9m)54m²$5,500–10,000

Alfresco / Patio Slab Cost Sydney

An alfresco or patio slab in Sydney costs $3,000–8,000 for a typical 25–50m² area. Exposed aggregate finish adds $1,000–2,000. Prices include N25 concrete, compacted base, reo mesh, and sealant.

For many homeowners, the alfresco slab is the highest-value concrete project because it directly extends your living space. Consider exposed aggregate for a premium finish at a moderate premium ($25–35/m² more than standard broom finish).

What Drives Cost Variation

  • Soil conditions: reactive clay (H1/H2) can add $3,000–8,000+ to a house slab through additional reinforcement and thicker edge beams
  • Reinforcement spec: engineer requirements vary dramatically. Simple SL72 mesh costs $8/m²; complex N-bar cages cost $30–50/m²
  • Site access: tight access requiring a pump adds $600–900 per day. Crane mats for soft ground add $50/day each
  • Finish type: broom finish is cheapest; exposed aggregate adds $25–35/m²; stencilled adds $35–60/m²
  • Concrete grade: N25 is standard; N32 or N40 for reactive soils or heavy loads adds $15–30/m³
  • Contractor competition: get 3+ quotes with identical specs. Labour rates vary 30–50% between contractors

Frequently Asked Questions

How much does a concrete slab cost in Sydney?
Concrete slab costs in Sydney in 2026 usually range from $10,000–28,000 for a house slab, $3,200–10,000 for a garage slab, $2,800–9,000 for an alfresco or patio slab, and $130–220/m² for paths.
How much does a concrete slab cost per m² in Sydney?
A basic concrete slab with 25 MPa (N25), 100mm depth, and broom finish costs $75–130/m² in Sydney. Garage floors or engineered slabs with 32 MPa (N32) often cost $90–150/m². House slabs usually cost $100–175/m².
What is the cheapest type of concrete slab?
A simple ground-bearing slab on flat, stable ground is usually cheapest: 25 MPa (N25), 100mm depth, broom finish, compacted DGB20 base, and DPM where required. Expect $75–100/m² for basic residential applications.
How much concrete do I need for a 10×10m slab?
A 10×10m slab at 100mm thick = 10m³ of concrete. Add 10% waste = 11m³. At $340–370/m³ for N25 in Sydney, material is about $3,740–4,070 before delivery, pump, labour, base, and reinforcement.
What concrete grade for a house slab?
25 MPa (N25) is common for residential ground-bearing slabs, but your structural engineer may specify 32 MPa (N32), N40, or a different mix for reactive soils and structural loads. Always follow the engineer's specification.
Does a concrete slab need a structural engineer?
House slabs always need a structural engineer report in NSW. Garage floors, alfresco slabs, and paths on stable ground typically don't, but check with your council.
How long does a concrete slab take to pour?
An 80–100m² house slab can be poured in one day with a full crew and pump. Smaller garage and alfresco slabs take half a day. The prep work takes 1–3 days before the pour.
How much do concrete footings cost in Sydney?
Strip footings for a house cost $150–300/lm (linear metre) in Sydney. Pad footings for pergolas and decks cost $400–800 each. Costs vary with soil conditions and engineer requirements.
How much is a garage slab in Sydney?
A standard single garage slab (6×6m = 36m²) costs $3,500–6,500 in Sydney. A double garage (6×9m = 54m²) costs $5,500–10,000.
How long does a concrete slab last?
A properly specified and installed concrete slab lasts 50+ years. Driveways and exposed slabs benefit from resealing every 5–7 years. Structural slabs inside buildings can last 100+ years.
What is a waffle pod slab?
A waffle pod slab uses polystyrene pods between the concrete ribs to reduce concrete volume while maintaining structural performance. Common in Sydney suburbs with reactive clay soils. Costs $120–180/m².
What is a raft slab?
A raft slab is a thickened edge slab with internal beams cast monolithically. It's the standard residential slab type in Sydney. Costs $100–175/m² depending on soil and engineer spec.

Ready to order concrete in Sydney?