- 1). Build your forms (framing) for your project being certain to securely anchor them.
- 2). Measure the inside dimensions (length, width and height) of the framing and record these measurements.
- 3). Multiply the length times the width times the height to determine the cubic area of your project. Example: A 10-foot square patio that will be 6 inches thick would be 120 inches x 120 inches x 6 inches = 86,400 inches.
- 4). Divide your answer by the number of cubic inches in a cubic yard (46,656 inches). For the example above it would be 86,400 inches divided by 46,656 inches = 1.85.
- 5). The answer to step 4 will be the amount of cubic feet of concrete you will need to complete your project.
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