Calculating the cubic meters of concrete you will need to pour in the area you have formed is easy. By following these simple steps, you can figure out the amount needed quickly and with little chance of over-ordering, or worse, ordering too little concrete for your pour.
Measure the length and width of the area in which you will pour the concrete in feet and inches. If the area is not shaped like a simple square or rectangle, divide it into sections that allow you to measure each section as close to a rectangle as possible. For example, if you are trying to pour a concrete pad that is 30 feet long but changes its width every 10 feet, you might wind up with the following set of measurements in order to break down the entire pour into a series of rectangles: 10 feet long by 20 feet wide 10 feet long by 15 feet wide 10 feet long by 10 feet wide
Measure the depth of the area you will be pouring in feet and inches. If you have multiple sections from Step 1, measure the depth for each section. Using the sample measurements from Step 1, your set of numbers may look like this: 10 feet long by 20 feet wide by 6 inches deep 10 feet long by 15 feet wide by 6 inches deep 10 feet long by 10 feet wide by 6 inches deep
Multiply the length times the width times the depth of each section. If you have different sections, add the results of each equation together to arrive at one total number. This number is the cubic feet in your pour. The total number of cubic feet in our sample would be 225 cubic feet.
Divide the total number of cubic feet in your pour by 27, the number of cubic feet in a cubic yard. In our sample pour, 225 cubic feet divided by 27 will equal 8.33 (round the number after the third decimal place for ease of figuring your concrete). You have 8.33 cubic yards in your sample pour.
Finally, convert the cubic yards in your pour to cubic meters by multiplying the cubic yards by 0.764554857992 (which is how many cubic meters are in a cubic yard). The total number of cubic meters in your sample pour is 6.37 (round again from the third decimal).
Add an additional 10 per cent of your total cubic meters of concrete that you know you will need to your order. This will cover any concrete lost through spillage and make sure you have enough.
Always double-check your initial measurements. Be careful when working with and around concrete. Do not to let it come in contact with your skin or eyes, keep a first aid kit handy and wear the appropriate personal protective equipment.