Concrete Wall Calculator
Estimate cast-in-place concrete wall volume, opening deductions, bags, form-contact area, placed weight and ready-mix cost.
Default project preview
3.78 yd³
Concrete bags
170
Net wall face
139 ft²
Two-face form area
278 ft²
Base volume
3.43 yd³
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 20 ft.
Wall height
Enter this project assumption in ft. The current imperial default is 8 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.
Openings per wall
Enter this project assumption in ft². The current imperial default is 21 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: 170.
Net wall face
after openings. Default preview: 139 ft².
Two-face form area
main wall faces only. Default preview: 278 ft².
Base volume
before allowance. Default preview: 3.43 yd³.
Placed weight
approximate wet concrete. Default preview: 15,272 lb.
Ready-mix cost
bagged option $1,190.00. Default preview: $622.93.
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 face area = length × height − openings. Concrete volume = net face area × thickness × quantity. Allowance is added before converting to ready-mix volume or bags.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: July 30, 2026
Use this calculator to estimate concrete for a rectangular cast-in-place wall after accounting for openings and waste. It is an ordering tool and does not determine wall thickness, reinforcement, footing or lateral-load capacity.
Calculation steps
- 1Calculate gross wall volume from length × height × thickness.
- 2Calculate and subtract full-depth opening volumes.
- 3Add the entered placement allowance.
- 4Convert to cubic yards or cubic metres and round purchasing appropriately.
Worked numerical example
A wall 40 ft long × 8 ft high × 8 in thick has 213.3 ft³ gross volume. Subtracting a 3 ft × 7 ft opening through the wall and adding 8% waste gives the planned order volume.
Purchasing and rounding
Ready-mix is commonly ordered to the supplier’s accepted increment. Confirm minimum load, short-load fees and pump residual volume.
Interpret the result
A large difference between gross and net volume usually comes from openings. Waste should reflect form leakage, pump line and placement conditions.
Page-specific assumptions
- Uniform wall thickness.
- Rectangular wall and openings.
- Openings pass through the full thickness.
- No pilasters or thickened zones unless added separately.
Common mistakes
- Using inches without conversion.
- Subtracting opening area but not volume.
- Ignoring thickened ends or pilasters.
- Selecting thickness without design.
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.
BuildMeter Guides
Understand the measurements and assumptions
Use these visible reference guides before changing project inputs or planning allowances.
FAQ
Concrete Wall Calculator questions
Should door and window openings be subtracted?+
Yes, subtract true through-openings for a closer concrete estimate. Embedded bucks and irregular edges may add waste.
Does form-contact area include wall ends?+
The displayed form area covers the two main faces. Ends, bulkheads, openings and construction joints need separate measurement.
Can this size a structural concrete wall?+
No. Structural capacity depends on loads, soil, reinforcement, foundations and applicable code.