How to calculate soil volume

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Soil volume is a measurement of the amount of soil in a particular area. You may need measurements of soil volume if you are filling a planter or a garden area. Measurements of soil volume can vary, depending on whether the soil is wet or dry, undisturbed or compacted.

Soil volume is usually calculated in cubic metres or cubic yards. Estimating and calculating soil volume can help you to plan and price outdoor projects.

Measure the width, length and depth of the soil.

Multiply these three measurements together to find the volume of the soil. For instance, if the soil measures 3 m long, 2 m wide and 0.5 m deep, multiply 3 times 2 times 1.5, to get 3 cubic metres. In imperial units, 6 feet long by 4 feet wide by 2 feet deep would mean multiplying 6 times 4 times 2 to get 48 cubic feet - the calculation is the same process regardless.

Multiply the cubic metres by 1.308 to if you want the volume in cubic yards, or divide the cubic feet value by 27. In this example, you would multiply 3 by 1.308 to get 3.924 cubic yards, or for the example in feet divide 48 by 27 to get 1.778 cubic yards.

State your answer as "bank cubic metres" (or feet or yards) if the soil is in an undisturbed, natural state. State your answer as "loose cubic metres" if the soil has been excavated; excavating causes soils to expand. State your answer as "compacted cubic metres" if the soil has been compacted; compacting soil makes it shrink in volume compared to its natural state.