Lava rock coverage 180 square feet per ton at 3” depth
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Flagstone coverage 125 square feet per ton up to 1 ½” thick
2”-4” rock coverage 65 square feet per ton
5”-12” rock coverage 45 square feet per ton
4” strip stone coverage 65 square feet per ton
How do I calculate how much landscape rock I need?
Divide the desired depth for your landscape rock in inches by 12 to convert it to feet. For instance, if you want the rock to be 2 inches deep, divide 2 by 12, which equals 0.1667 feet. Multiply the length by the width by the desired depth in feet for your landscape rock to find the number of cubic feet you will need.
To measure the driveway in cubic feet, multiply the length by width by depth. For cubic yards, divide the total cubic feet by 27. Because one cubic yard of gravel is equal to 1.13 tons, you can multiply your total cubic yards by 1.13 to convert this measurement to tons.