How much does a concrete slab cost?
Concrete slab prices in Australia generally run from about $75 to $170 per square metre supplied and laid, depending on the slab type, finish and how easy your site is to work on. Use the calculator below for an indicative range for your job, then get free quotes from verified local concreters to confirm.
Length × width. A single garage ≈ 20 m², a double ≈ 36 m².
Common questions
How much does a concrete slab cost per square metre in Australia?+
Most plain concrete slabs run about $75–$120 per m² supplied and laid. Reinforced or thicker structural slabs sit higher (roughly $90–$170 per m²), and decorative finishes like exposed aggregate or polished add more again. Site access, slab size and your location all move the final figure.
How much is a concrete slab for a shed or garage?+
A single garage slab is around 18–22 m² and a double around 36 m². At standard rates that's roughly $1,500–$2,800 for a single and $3,000–$5,000 for a double — more for reinforced or structural slabs, or a decorative finish. Enter your size above for a tailored range.
Does exposed aggregate cost more than plain concrete?+
Yes. Exposed aggregate and other decorative finishes typically add around $25–$55 per m² over a plain broom finish, because of the extra materials and labour to wash back and finish the surface. Polished concrete can add even more.
How thick should a concrete slab be?+
A typical residential slab — paths, patios, a garage floor — is around 100 mm. Slabs carrying heavier loads (a shed, a house, or a driveway with vehicle traffic) are usually thicker and reinforced with steel mesh or bar, which is why 'structural' slabs cost more. Your concreter or engineer will confirm what your job needs.