Concrete Tube Calculator
80lb Bags Needed
0
Estimated Quikrete Bags
60lb Bags Needed
0
Total Cubic Yards
0
Ready to pour?
Check Mixer Prices →How to Use This Concrete Tube Calculator
Pouring concrete footings is the most critical part of building a deck or pole barn. This free concrete tube calculator (often called a Sonotube calculator) tells you exactly how many bags of pre-mix concrete you need based on the diameter and depth of your hole.
Key Features:
- Multiple Bag Sizes: Instantly see results for both standard 80lb and lightweight 60lb bags.
- Waste Factor Included: We automatically add a 5% safety margin to account for spillage and uneven hole bottoms.
- Cubic Yards: For large commercial projects, we provide the total cubic yardage so you can order a cement truck if necessary.
Common Questions About Concrete Footings
What is the formula for concrete in a tube?
The math requires calculating the volume of a cylinder: V = π × r² × h (Pi times Radius squared times Height). Then, you convert cubic feet into bags. One 80lb bag of Quikrete yields approximately 0.6 cubic feet of concrete.
How deep should my footings be?
Your concrete footings must extend below the frost line to prevent “frost heave,” which can push your posts out of the ground in winter. In most northern US states, this is between 36″ and 48″. Check your local building codes before digging.
Which tube size should I use?
- 8-inch: Light decks, fence posts, and mailboxes.
- 10-inch: Standard residential decks and porches.
- 12-inch: Heavy load-bearing beams and pole barns.
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