How to Figure the Area Per Bag of Cement
- 1). Prepare the area that the cement will be poured in. Use a shovel to level the ground as much as possible. When the area is level, use a hammer and nails to build forms out of boards. These forms serve as a mold that the wet cement is poured into.
- 2). Measure the area that the cement will be poured into so that you know how its size and shape will be restricted. Use a tape measure to make a measurement of the length, the width and the depth of the form. Make note of each measurement in inches. For example, instead of 1 foot 2 inches, you would notate 14 inches.
- 3). Calculate how many cubic feet of material the cement form will hold. Multiply length by width, then multiply the answer by the depth of the form. This will give you the number of cubic inches. Divide this number by 12 to determine the number of cubic feet that will be required to fill the form.
- 4). Determine how large your bag of cement is. Most cement is sold in bags weighing either 60 or 80 pounds. A 60 pound bag of cement produces enough material to fill 0.45 cubic foot. An 80 pound bag can fill 0.6 cubic foot. With such dramatic differences, it is important to know how large your bag of cement is. Read the label to determine the size of the bag.
- 5). Determine how many bags will be required to fill the form. If you are working with 60 pound bags, divide the total number of cubic feet by 0.45 to determine how many bags are needed. If you have 80 pound bags of cement, divide the total by 0.6 to determine how many bags will be needed.
- 6). Divide the length of the form by the number of bags. For example, if your cement form is 10 feet long and it will take 4 bags to fill the cubic area of the form, then divide 10 by 4 to get 2.5 feet. This tells you how large an area each bag will cover if the form is filled to the complete width and depth. In this example, the area would be a strip, filled to max width and depth, that measures 2.5 feet long.
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