16×20 Concrete Slab (6 inches): Yards, Feet & Bags
This 16 ft x 20 ft slab is perfect for a patio or gazebo base. Decide between bags or ready-mix based on your access and waste factor.
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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)
For accurate ordering, round to 0.25 yd³ and check yield on the label for your chosen concrete mix.
Ensure your base is well-prepared and consider thickened edges for added strength.
Finish your surface as desired and allow for proper curing by keeping it moist and shaded.
How to Estimate This Slab in 3 Steps
Measure
Length 16 ft, width 20 ft, thickness 6 in.
Compute Volume
Area: 320 sq ft → volume: 160.0 ft³ → 5.93 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 should I consider when choosing between bags and ready-mix concrete?
Consider your project size, site access, and whether you can handle mixing on-site or prefer a ready-to-use option.
How do I determine the right thickness for my concrete slab?
Thickness depends on the intended use; heavier loads may require a thicker slab for durability.
What are the key steps in preparing the base for my slab?
Clear the area of debris, level the ground, and compact the soil to create a stable foundation.
How can I prevent cracking during the curing process?
Keep the slab moist and covered to protect it from extreme temperatures and direct sunlight.
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