How to Calculate the Amount of Cement
- 1). Prepare a detailed drawing of your project. For this example, we will be constructing a 10-foot square patio with a 20-foot walkway.
- 2). Calculate the cubic area of the patio by multiplying depth times length times width. If the 10-foot by 10-foot patio will be 4 inches thick (10 feet = 120 inches):
4 x 120 x 120 = 57,600 cubic inches - 3). Calculate the cubic area of the walkway by multiplying depth times length times width. The 20-foot walkway will be 36 inches wide and 4 inches thick:
240 x 36 x 4 = 34,560 cubic inches - 4). Add the two numbers together to determine your total cubic area:
57,600 + 34,560 = 92,160 cubic inches - 5). Divide the answer from Step 4 by 46,656 (the number of cubic inches in a cubic yard):
92,160 / 46,656 = 1.97
This is the number of cubic yards of concrete needed to complete this project.
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