Cost Guides
Concrete Slab Cost QLD: Shed, Garage & House Slabs (2026)
By Fraser Coast Concreting · 20 June 2026
Quick answer
As a guide, a plain concrete slab in Queensland typically costs $80–$120/m² supplied and laid. A common 6x6m (36m²) shed slab usually runs about $2,900–$4,300, and a 6x9m (54m²) slab around $4,300–$6,500. Thickness, reinforcement, site prep and soil type all change the price. A written quote is the only accurate figure.
Whether it’s a slab for a new shed, a garage or a house extension, the price comes down to a handful of factors: size, thickness, reinforcement, site prep and soil. This guide gives you realistic 2026 ranges for Queensland, with a table of common shed slab sizes so you can budget quickly.
These are indicative figures, presented as typical ranges. The only accurate price is a written quote based on your actual site.
Concrete slab cost per m² in QLD
For a standard plain slab, expect roughly $80–$120/m² supplied and laid in 2026. Where you sit in that range depends mostly on thickness, the reinforcement specified and how much site preparation is needed.
A domestic slab is commonly 100mm thick with steel mesh. Slabs that carry vehicles, machinery or heavy storage are often poured thicker (125mm or more) with heavier reinforcement, which lifts the per-m² cost.
Shed slab cost by size
Here are indicative totals for common shed slab sizes at the typical $80–$120/m² range. Use these to get a rough budget before you call for a quote.
| Shed size | Area | Indicative cost (plain slab) |
|---|---|---|
| 6 x 6 m | 36 m² | $2,900 – $4,300 |
| 6 x 7 m | 42 m² | $3,400 – $5,000 |
| 7 x 7 m | 49 m² | $3,900 – $5,900 |
| 6 x 9 m | 54 m² | $4,300 – $6,500 |
| 7 x 9 m | 63 m² | $5,000 – $7,600 |
| 9 x 9 m | 81 m² | $6,500 – $9,700 |
As a guide only. Bigger slabs often cost a little less per m² because fixed costs are spread further, while small slabs can cost slightly more per m².
House and garage slabs
House and garage slabs are usually engineered to a structural plan, with footings, thickened edges and reinforcement designed for the building and the soil. Because of the engineering, formwork and extra concrete in the beams, they generally cost more per m² than a simple shed slab. These jobs are best quoted from the engineer’s plans rather than a rule of thumb.
What changes the cost of a slab
- Thickness. A 100mm domestic slab is the baseline. Thicker pours for sheds, garages, sheds storing vehicles or workshops use more concrete and cost more.
- Reinforcement. Steel mesh is standard; heavier mesh or added bar increases strength and price.
- Site preparation. Clearing, levelling, importing and compacting road base, and setting formwork all add to the cost. Sloping or uneven ground costs more to prepare.
- Fall and finish. Slabs often need a slight fall for drainage, and a particular finish (trowel, broom) affects labour.
- Footings and edge beams. Sheds and buildings usually need thickened edges or footings, which add concrete and steel.
- Reactive (clay) soil. Much of the Fraser Coast and Maryborough sits on reactive clay that swells and shrinks with moisture. Slabs on reactive soil often need stronger engineering to resist movement and cracking, which adds cost but is well worth it.
Why soil matters on the Fraser Coast
Reactive clay is common around Maryborough and parts of Hervey Bay. When it gets wet it expands, and when it dries out it contracts, and that movement can crack an under-built slab. A properly engineered slab with the right footings, reinforcement and base preparation is the best insurance against this. It’s one of the main reasons we don’t recommend cutting corners on prep.
How to compare slab quotes
Make sure each quote states:
- Slab thickness and reinforcement type
- Site preparation and base material included
- Footings or edge beams where required
- Whether the slab is engineered for your soil
- Site clean-up and rubbish removal
Get an accurate slab quote
The ranges above are great for budgeting, but every slab depends on your site and soil. Fraser Coast Concreting provides free written quotes for concrete slabs across Hervey Bay, Maryborough, Rainbow Beach and Tin Can Bay. Get your free quote here and we’ll give you a clear, itemised price for your shed, garage or house slab.