How to Calculate the Volume of a Silo

By Michael O. Smathers; Updated April 24, 2017
A silo is shaped like a cylinder.

If you plan to use a silo for storage space for grain, you should calculate how much space you have available in total. A silo is a relatively cylindrical shape with a half-dome on top, so you can use the formulas for the volume of a sphere and a cylinder to determine how much storage space you have in your silo.

Attach the bottom of the tape measure to the base of the silo. Climb up to the top, lay the tape measure against the wall and note the measurement.

Find the center point of the silo's interior and measure from it to any point on a wall. This gives you the radius.

Multiply pi, or 3.14, by the square of the radius to calculate surface area. Multiply the surface area by the height of the cylindrical portion of the silo to determine that area. A silo with a radius of 10 feet and a height of 20 feet for the cylinder has a volume of 6,280 cubic feet.

Determine the area of the dome portion of the silo with the sphere volume formula: (4/3)(pi)(r^3). Divide the result by 2 to find the formula for the area of a dome. The result should be 2,093.32 cubic feet.

Add the two portions. The result should be 8,373.32 cubic feet.

About the Author

Michael Smathers studies history at the University of West Georgia. He has written freelance online for three years, and has been a Demand Studios writer since April 2009. Michael has written content on health, fitness, the physical sciences and martial arts. He has also written product reviews and help articles for video games on BrightHub, and martial arts-related articles on Associated Content.