Crushed limestone is a popular material used to make roads, driveways and parking areas. Figuring the amount you need for a paving project at your home is complicated by the fact that limestone is sold by the ton, but the easiest way to measure your needs is to determine how many cubic yards of the material to purchase. To get the right amount, you will have to make some calculations.

Measure the dimensions of the area you plan to cover with crushed limestone in yards, using a measuring tape.

Determine the depth of crushed limestone you plan to install. On bare soil, four to six inches will be needed to adequately pack and compress into a good driveway surface.

Perform the calculations to determine the square yards of surface area then multiply the square yards by the fraction of a yard in depth you want. This will produce the cubic yards of material you will need. For example: a driveway measuring three-yards wide by twenty-yards long has a surface area of 60 square yards. Multiply 60 by 1/6th of a yard (six-inches) to determine you will need 10 cubic yards of limestone.

Multiply the cubic yards of crushed limestone you need by 2700 (the number of pounds in a cubic yard) to determine the number of pounds needed, then divide that quotient by 2000 to determine the number of tons to order.