Construction
Verified calculator with a transparent formula
Concrete Retaining Wall Calculator.
Estimates the volume of concrete needed for a retaining wall, including the wall body and a simple footing, based on dimensions.
Your inputs
How it works
- 1
Convert wall thickness from inches to feet by dividing by 12.
- 2
Calculate wall volume: length × height × thickness (in feet).
- 3
Convert footing width and thickness to feet, then compute footing volume: length × width × thickness.
- 4
Add wall and footing volumes to get total concrete volume.
(wall_length * wall_height * (wall_thickness/12)) + (wall_length * (footing_width/12) * (footing_thickness/12))Frequently asked questions
Does this calculator include gravel backfill or rebar?
No, it only estimates concrete volume for the wall and footing. You'll need to add extra for waste and separate materials for reinforcement.
How do I convert cubic feet to cubic yards?
Divide the total cubic feet by 27. For example, 120 cu ft ÷ 27 ≈ 4.44 cubic yards.
Should I order extra concrete?
Yes, it's common to add 5-10% for waste, spillage, and uneven subgrade. Multiply the total by 1.05 to 1.10.
Explore this calculator category
Results
Formula checkedEstimate for general guidance only — verify important decisions with an appropriate professional.
How it works
Estimates the volume of concrete needed for a retaining wall, including the wall body and a simple footing, based on dimensions.
- Convert wall thickness from inches to feet by dividing by 12.
- Calculate wall volume: length × height × thickness (in feet).
- Convert footing width and thickness to feet, then compute footing volume: length × width × thickness.
- Add wall and footing volumes to get total concrete volume.
Formulas
The math behind this calculator, written out so you can verify the result.
Wall Volume
Multiply the wall length, height, and thickness (all in feet) to get the volume of the wall body.
Example:
Input: L=20 ft, H=4 ft, T=1 ft (12 in)
Calculation: 20 × 4 × 1 = 80 cu ft
Result: 80 cubic feet
Footing Volume
Multiply the wall length by the footing width and depth (both in feet) to get the footing volume.
Example:
Input: L=20 ft, W=2 ft (24 in), D=1 ft (12 in)
Calculation: 20 × 2 × 1 = 40 cu ft
Result: 40 cubic feet
Real-world use cases
Where this calculation shows up in everyday life.
Project Planning
Estimate concrete needs before ordering to avoid shortages or excess.
Example: A 30 ft long, 5 ft high wall with 12 in thickness and 24 in footing.
Cost Estimation
Multiply the volume by local concrete prices to budget the project.
Example: 120 cu ft × $150 per cubic yard ≈ $667.
Material Comparison
Compare different wall thicknesses or footing sizes to see how they affect concrete volume.
Example: Thicker walls use more concrete but may reduce rebar needs.
Tips and common mistakes
Tips
- Always add 5-10% extra for waste and spillage.
- Measure dimensions accurately; errors compound in volume.
- Consider frost depth for footing thickness in cold climates.
- Check local building codes for minimum thickness requirements.
Common Mistakes to Avoid
- Forgetting to convert inches to feet before multiplying.
- Ignoring the footing volume and only calculating the wall.
- Using the same thickness for wall and footing when they differ.
Assumptions and limitations
- Use the stated inputs and units.
- Results are estimates for planning and education.
- Check measurements and source data before making an important decision.