Concrete Retaining Wall Volume Calculator
Estimate concrete volume, bag quantity, wall-face area, form-contact area, placed weight and cost for straight cast-in-place retaining-wall sections.
Default project preview
3.26 yd³
Concrete bags
147
Net wall face
120 ft²
Two-face form area
240 ft²
Total wall length
30 ft
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Wall length
Enter this project assumption in ft. The current imperial default is 30 ft.
Wall height
Enter this project assumption in ft. The current imperial default is 4 ft.
Wall thickness
Enter this project assumption in in. The current imperial default is 8 in.
Equal wall sections
Enter this project assumption in a unitless value. The current imperial default is 1. Minimum: 1.
Total opening area
Enter this project assumption in ft². The current imperial default is 0 ft². Minimum: 0.
Extra allowance
Enter this project assumption in %. The current imperial default is 10 %. Minimum: 0. Maximum: 50.
Concrete yield per bag
Enter this project assumption in ft³. The current imperial default is 0.6 ft³.
Ready-mix price
Enter this project assumption in per yd³. The current imperial default is 165 per yd³. Minimum: 0.
Price per bag
Enter this project assumption in a unitless value. The current imperial default is 7. Minimum: 0.
How to read the outputs
Concrete bags
rounded full bags. Default preview: 147.
Net wall face
openings deducted. Default preview: 120 ft².
Two-face form area
wall faces only. Default preview: 240 ft².
Total wall length
all sections. Default preview: 30 ft.
Placed weight
planning density. Default preview: 13,185 lb.
Cost comparison
ready-mix / bags. Default preview: $537.78 / $1,029.00.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Net wall face = length × height × sections − openings. Volume = net face × wall thickness, followed by the entered allowance.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: July 30, 2026
Estimate concrete volume for a designed retaining-wall stem and footing. The calculator handles geometry only; wall height, thickness, reinforcement, drainage, sliding and overturning resistance require qualified design.
Calculation steps
- 1Enter wall length and the approved stem dimensions.
- 2Calculate footing volume separately from the stem.
- 3Add keys, pilasters or stepped sections as separate shapes.
- 4Apply placement allowance and round to supplier increments.
Worked numerical example
A 40 ft wall with an 8 in × 5 ft stem contains 133.3 ft³. A 30 in × 12 in footing adds 100 ft³, for 8.64 yd³ total before allowance.
Purchasing and rounding
Coordinate concrete deliveries with reinforcement, forms, lift sequence and access. Drain rock, perforated pipe, waterproofing and geotextile are separate quantities.
Interpret the result
Concrete volume does not indicate wall stability. Taller walls, surcharge loads, weak soils and water pressure can govern the design even when volume is modest.
Page-specific assumptions
- Dimensions come from approved structural details.
- Wall and footing sections are uniform or calculated separately.
- Reinforcement volume is not deducted.
Common mistakes
- Designing wall thickness from a volume calculator.
- Omitting footing or shear-key volume.
- Ignoring drainage and hydrostatic pressure.
- Using retained height without checking total structural height.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
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FAQ
Concrete Retaining Wall Volume Calculator questions
Does this include the retaining-wall footing?+
No. Estimate the footing separately with the wall-footing calculator.
Should both wall faces be counted for concrete?+
No. Concrete volume uses one face area times thickness; two faces are shown only as a formwork guide.
Can this design a retaining wall?+
No. Structural and geotechnical design are outside this material calculation.