Shed Slabs & Garage Slabs Brisbane — Engineered for Your Build
Whether you're building a backyard shed, a double garage, a workshop, or a granny flat, it all starts with a solid concrete slab. At Concrete Concepts Group, we pour shed slabs and garage slabs engineered to your exact specifications — matching your shed manufacturer's requirements, your engineer's design, and Brisbane City Council's building codes.
A shed slab is more than just a flat piece of concrete — it's the foundation that your entire structure sits on. Getting it wrong means cracked floors, misaligned walls, and costly repairs. We work directly with your shed manufacturer or builder to ensure the slab dimensions, bolt-down locations, edge beam depths, and concrete strength all match their specifications exactly.
Brisbane's reactive clay soils present unique challenges for shed slabs. Soil movement can cause cracking and heaving if the slab isn't designed correctly. We follow Australian Standard AS 2870 for residential slabs and work with structural engineers when required to ensure your slab is designed for your specific site conditions — including soil reactivity class, drainage, and load requirements.
For sheds over 10m², Brisbane City Council typically requires a building approval. This includes an engineer-designed slab with specific edge beam depths, reinforcement, and concrete strength. We can pour to your engineer's design or connect you with a structural engineer who specialises in shed and garage slabs. For smaller sheds, a standard 100mm slab with SL72 mesh is usually sufficient.
We handle everything from site excavation and compaction to formwork, reinforcement, bolt-cage installation, and the final pour. Our slabs are power-floated for a smooth, level finish that's ready for your shed builder to start. We also install any required plumbing penetrations, electrical conduit, and termite barriers as part of the slab preparation.
Why Choose Concrete Concepts for Shed Slabs & Garage Slabs Brisbane
Our Process
Site Assessment
We inspect your site, check soil conditions, confirm access for concrete trucks, and review your shed manufacturer's slab specifications.
Engineering Review
We review the engineer's slab design (or arrange one if needed), confirm dimensions, edge beam depths, reinforcement, and bolt-down locations.
Excavation & Preparation
We excavate to the required depth, compact the sub-base, install termite barriers if required, and lay any plumbing or electrical conduit.
Formwork & Reinforcement
We set formwork to exact dimensions, install steel reinforcement (mesh and/or rebar), and position bolt-down cages to your shed manufacturer's template.
Pour & Finish
We pour the concrete, vibrate to remove air pockets, screed to level, and power-float for a smooth finish. Bolt cages are checked for alignment before the concrete sets.
Shed Slabs & Garage Slabs Brisbane Pricing
Shed slab costs depend on size, soil conditions, and engineering requirements. Here are typical Brisbane prices:
| Type | Price Range | Estimate | Notes |
|---|---|---|---|
| Small Shed Slab (up to 20m²) | $85 – $110/m² | N/A | 100mm thick, SL72 mesh |
| Standard Garage Slab (30-50m²) | $75 – $100/m² | $2,600 – $5,000 | 100-125mm, SL82 mesh |
| Large Shed/Workshop (50-100m²) | $70 – $95/m² | $3,500 – $4,750 | Engineered design, edge beams |
| Granny Flat Slab (40-60m²) | $80 – $110/m² | $4,000 – $5,500 | Full engineering, plumbing included |
All prices include GST, excavation (standard depth), formwork, reinforcement, concrete supply, bolt cages, power-float finish, and curing. Deep excavation, rock removal, or difficult access may incur additional costs.
Frequently Asked Questions
How thick should a shed slab be?
For a standard garden shed, 100mm of 20MPa concrete with SL72 mesh is typically sufficient. For garages and larger sheds, 100-125mm of 25MPa concrete with SL82 mesh is recommended. Sheds designed for heavy equipment or vehicles may require 150mm+ with additional reinforcement. Your shed manufacturer's specifications will dictate the exact requirements.
Do I need an engineer for a shed slab?
For sheds over 10m² that require building approval, Brisbane City Council typically requires an engineer-designed slab. The engineer will specify the slab thickness, edge beam depths, reinforcement, and concrete strength based on your soil conditions and the shed loads. For small garden sheds under 10m², a standard slab design is usually sufficient.
How much does a shed slab cost in Brisbane?
Shed slab costs in Brisbane range from $70 to $110 per square metre depending on size and complexity. A standard single garage slab (36m²) costs approximately $2,700 to $3,600, while a large workshop slab (80m²) ranges from $5,600 to $7,600. Our quotes include excavation, formwork, reinforcement, concrete, bolt cages, and power-float finishing.
Can you install bolt-down cages for my shed?
Yes — bolt-down cage installation is included in our shed slab service. We position the cages to your shed manufacturer's template with millimetre accuracy. The cages are secured to the reinforcement mesh before pouring and checked for alignment during the pour. This ensures your shed frame bolts down perfectly.
How long before I can build on the slab?
Concrete reaches sufficient strength for shed construction after 7 days. Full design strength (28 days) is reached after 4 weeks, but most shed builders are comfortable starting at 7 days. We'll advise your builder on the appropriate timing based on the concrete strength and weather conditions.
Need a shed slab? Get your free quote — we'll match your manufacturer's specs exactly.
QBCC Licensed #15299707 · Fully Insured · Free On-Site Quotes · Serving All of Brisbane & SEQ
Shed Slabs & Garage Slabs Brisbane — Areas We Service
We provide shed slabs & garage slabs brisbane services across Brisbane and South East Queensland, including: