Double Garage Slab Concrete Requirements
Double garages have become standard in Australian new homes, providing space for two vehicles plus storage. At 36 square metres, a double garage slab represents a significant concrete project that typically requires professional design input and potentially professional installation.
Standard Dimensions and Layout
Internal dimensions of 6x6 metres provide comfortable space for two vehicles. This allows approximately 2.7 metres per vehicle bay with space for opening doors. Some designs extend to 6x7 or 6x8 metres for additional workshop or storage space behind the vehicle parking areas.
Volume and Cost Expectations
A 6x6 metre slab at 125mm depth requires 4.5 cubic metres of concrete for the slab alone. Adding typical edge beams might increase this to 5-6 cubic metres total. At current prices, expect concrete costs of $1,400-$2,500 plus delivery, pumping, and any professional labour.
Engineering Requirements
Double garages almost always require engineered plans including specific slab and footing details. Your engineer will consider soil conditions, garage structure, and any additional loads from storage or living spaces above. These plans form part of your building approval documentation.
Professional Pour Considerations
A 5+ cubic metre pour with edge beams and bolt placements challenges even experienced DIYers. Most homeowners engage professional concreters for this work while potentially handling site preparation themselves. The cost difference between DIY and professional installation is modest relative to the risk of getting it wrong.
Reinforcement Specifications
Engineer-specified reinforcement typically includes SL82 or SL92 mesh in the slab plus additional bar reinforcement in edge beams. Reinforcement must be correctly positioned and tied, with certification often required before council inspection. Follow engineering details exactly for both structural integrity and approval compliance.
Services and Penetrations
Plan locations for floor wastes, electrical conduits, and any other services before pouring. It's far easier to cast sleeves or pipes into fresh concrete than to cut through afterwards. Coordinate with your electrician and plumber to have penetrations correctly positioned.
Need Different Dimensions?
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