You need a pour quantity before you call dispatch or compare your concrete sub’s takeoff. Choose a slab, rectangular footing, or solid round column. Enter its dimensions, identical-piece count, and waste allowance to estimate cubic yards.
Measure the filled shape
For a slab, enter length and width in feet and thickness in inches. For a footing, use length in feet with width and depth in inches. For a column, enter the inside filled diameter in inches and filled height in feet. Check the unit beside each field before copying dimensions from your site notes.
Use the quantity field only for pieces with identical dimensions. Split a stepped footing or changing slab thickness into separate sections. Record each section on your sketch so another person can trace the volume back to the pour.
Check the formula and allowance
Sakrete’s estimating guide calculates rectangular volume and divides cubic feet by twenty-seven to obtain cubic yards. This tool converts inches to feet before multiplying. For columns, it derives volume from circular area times height: pi times radius squared times height.
The calculator multiplies net volume by one plus your waste percentage divided by one hundred. NRMCA’s ordering guide discusses contingency above plan quantities. Choose the allowance with the people responsible for the pour rather than treating the initial zero as an ordering recommendation.
Read the result before placing the order
For example, a nine-by-nine-foot slab at four inches thick contains one cubic yard. Entering ten percent waste produces 1.10 cubic yards. The tool’s upward quarter-yard option gives 1.25 cubic yards. Confirm that increment with the supplier.
For one delivery covering several shapes, add net volumes before applying one shared allowance and order rounding. Adding separate rounded orders changes the total. The model does not subtract reinforcement, embedded posts, or voids; keep those assumptions with the takeoff.
Check the inputs and results
Scroll to read all columns.
| Input | Unit and accepted values |
|---|---|
| Shape | Slab, rectangular footing, or solid round column |
| Slab dimensions | Length and width: feet, greater than zero through 10,000. Thickness: inches, greater than zero through 1,200. |
| Footing dimensions | Length: feet, greater than zero through 10,000. Width and depth: inches, greater than zero through 1,200. |
| Column dimensions | Diameter: inches, greater than zero through 1,200. Height: feet, greater than zero through 10,000. |
| Identical pieces | Whole count, 1 through 100,000 |
| Waste | Percent, 0 through 100 |
Enter positive dimensions and a whole piece count. Waste can be zero. The quarter-yard option rounds the full adjusted volume upward; confirm that increment with dispatch.
Before you release the pour
Keep feet, inches, and cubic yards distinct; NIST’s unit table provides conversion references. Record the filled dimensions before comparing a supplier’s quantity.
For round forms, check the selected product’s dimensions and instructions against the Sonotube round-form reference. This calculator models a solid cylinder, without a widened base or hollow core.
Assign curing separately using NRMCA’s curing guidance. Confirm the permit checkpoint through Raleigh’s inspection sequence or your local office before releasing the pour.
Review the takeoff with the concrete sub and the concrete supplier. Use the material-delivery guide to assign site access and the receiver.
Return to the construction tools hub for the other quantity checks and printable records.
Where Cercha fits
Use the Cercha app’s Search filters to find a concrete trade by trade, ZIP code, and radius. Review portfolio photos and use Messages to discuss the pour scope. Keep the quantity check with your project notes.