Concrete Footing Calculator
Calculate the concrete volume for round deck footings and convert it to 60lb or 80lb bags.
Concrete Footings
Total volume14.1 cu ft (0.52 cu yd)
Bags needed32
Material cost$208.00
Line total$208.00
Deckworks saves the math with the line item so your customer sees exactly how you priced it.
How the math works
- 01Volume per footing = π × (diameter ÷ 2 in feet)² × depth in feet.
- 02Total cubic feet = volume per footing × number of footings.
- 03A 60lb bag yields about 0.45 cu ft; an 80lb bag yields about 0.60 cu ft.
- 04Bags = total cubic feet ÷ bag yield, rounded up.
Common questions
How deep should deck footings be?
Below your local frost line — commonly 36in to 48in in cold climates and 12in to 24in in warm ones. Your building department sets the number.
60lb or 80lb bags?
80lb bags mean fewer trips and fewer bags to mix, but 60lb bags are easier to handle solo. The concrete volume is identical either way.
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