A garage slab needs to be more than just concrete — it must be engineered to handle the weight of vehicles, resist oil and water, and provide long-term durability. Whether you’re building a new garage or upgrading an old one, choosing the right slab thickness, reinforcement, and finish is crucial. This guide explains the key requirements and typical costs of garage slabs in Melbourne (2025).
Recommended Thickness for Garage Slabs
The thickness of your garage slab depends on whether it’s a single, double, or heavy-duty garage. For most residential garages in Melbourne, a 100mm reinforced slab is the standard. However, if you plan to store heavier vehicles, trailers, or machinery, a 125mm–150mm slab may be recommended.
General thickness guide:
- Single garage – 100mm slab with SL72 mesh
- Double garage – 125mm slab with SL82 mesh
- Heavy-duty / workshop garage – 150mm slab with additional reinforcement
Reinforcement for Garage Slabs
Reinforcement prevents cracking and ensures your garage slab can handle constant vehicle use. Most garage slabs use SL72 or SL82 steel mesh, with 25–32 MPa concrete strength. For heavy-duty garages, thicker reinforcement and additional edge beams may be required.
Learn more about reinforcement on our Concrete Slabs service page.
Garage Slab Costs in Melbourne
Garage slabs in Melbourne typically cost between $80–$120 per m² for standard residential use. For reinforced or heavy-duty slabs, costs can rise to $130–$160 per m². Overall costs depend on size, site access, soil type, and engineering requirements.
Average project costs:
- Single garage slab: $3,500–$5,000
- Double garage slab: $5,000–$8,000
- Heavy-duty garage / workshop: $8,000–$12,000+
Other Considerations for Garage Slabs
Beyond thickness and reinforcement, consider sealing your garage slab to protect against oil, water, and tyre stains. Sealed slabs are easier to clean and last longer, especially in Melbourne’s varied climate. Drainage and proper site preparation are also essential to avoid future issues.
See our Concrete Driveways and Concrete Finish Types pages for finish and design options.
Further Reading
Australian Standards (AS 2870 – Residential Slabs & Footings) – https://www.standards.org.au/
Concrete Institute of Australia – https://www.concreteinstitute.com.au/
Get a Free Quote for a Garage Slab in Melbourne
At Sturdy Concreter, we install garage slabs designed for strength, safety, and longevity. Whether it’s a single garage or a heavy-duty workshop, we’ll deliver a reinforced slab tailored to your needs. Contact us today for a free quote and expert advice.