6×12 Concrete Slab (6 inches): Yards, Feet & Bags
This 6 ft x 12 ft concrete slab, at 6 inches thick, works well as a base for a shed or an AC pad. Decide between using bags or ready-mix based on your site access and project size.
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Quick Answer
Tip: Always confirm the yield printed on your bag label. Bag yield guide
Project Notes (Unique)
Check yield on the label and round to 0.25 yd³ when ordering to ensure you have enough material for your project.
Ensure your base is properly prepared and forms are secure to prevent shifting during the pour.
Finish the surface as desired and allow the slab to cure adequately, keeping it moist during the process for optimal strength.
How to Estimate This Slab in 3 Steps
Measure
Length 6 ft, width 12 ft, thickness 6 in.
Compute Volume
Area: 72 sq ft → volume: 36.0 ft³ → 1.33 yd³.
Add Waste
Add a small buffer for spillage and uneven subgrade, then round up when ordering.
Planning Notes
Common uses: shed base, ac pad, small patio section.
For more context and conversions, see the Concrete Calculator hub.
Frequently Asked Questions
Should I use bags or ready-mix for my concrete slab?
Choose bags for smaller projects or limited access, while ready-mix is better for larger pours with easier delivery.
How do I account for waste when ordering concrete?
Always order a little extra to cover spillage and miscalculations; it's better to have a small buffer than to run short.
What should I consider when preparing the base for my slab?
Ensure the ground is level and compacted; a solid base is crucial to prevent future settling and cracking.
How thick should my concrete slab be for a shed base?
A thickness of around inches is generally sufficient for light structures, but consider the load it will bear.
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