10×20 Concrete Slab (4 inches): Yards, Feet & Bags
A 10 ft x 20 ft slab is perfect for a patio or gazebo base. Decide between bags or ready-mix based on access and waste considerations before starting your project.
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Quick Answer
Tip: Always confirm the yield printed on your bag label. Bag yield guide
Large pour: consider ready-mix delivery for speed and consistent results. Bag counts this high can take significant mixing time.
Project Notes (Unique)
When ordering, round to 0.25 yd³ and check yield on the label to ensure you have enough material for your slab.
Ensure your base is well-prepared and forms are sturdy to prevent shifting or settling during the pour.
For a smooth finish, use a float and allow the slab to cure naturally, keeping it moist as needed.
How to Estimate This Slab in 3 Steps
Measure
Length 10 ft, width 20 ft, thickness 4 in.
Compute Volume
Area: 200 sq ft → volume: 66.7 ft³ → 2.47 yd³.
Add Waste
Add a small buffer for spillage and uneven subgrade, then round up when ordering.
Planning Notes
Common uses: patio, gazebo base, walkway section.
For more context and conversions, see the Concrete Calculator hub.
Frequently Asked Questions
What are the advantages of using ready-mix concrete over bags?
Ready-mix is convenient for larger projects, saving you time and reducing the need for multiple trips to the store.
How should I prepare the base for my slab?
Excavate to a stable subgrade, compact the soil, and add a gravel layer for drainage before pouring.
What thickness should I choose for my slab?
A thickness of inches is generally sufficient for patios and walkways, but consider heavier loads for thicker options.
How do I determine how much concrete I need?
Measure the area and depth, then account for a waste factor to ensure you have enough material.
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