Estimating Landscape Stone Projects
To help you plan your landscaping project and compute the rock you will need, we have provided an estimating guide below. We welcome questions and are happy to help you figure the appropriate volume of rock to order.
Please remember that you will need extra rock to create roads or paths in muddy areas. If your substrate is dry, a 1 ½” thick layer of gravel may be enough. If your rock size is larger, please use the size of the largest rocks in the mix to compute the depth of a single layer of coverage (2” diameter rocks means that your coverage must be at least 2” thick).
A note about rock sizes: The rock screening and sorting process works well, but there will always be some variation in each load of rock. For example, the screen with a mesh size of 4” x 4” tends to sort out rocks in the 2” – 4” range. However, it is possible for rocks 4” in diameter but longer than 4” to slip through the mesh along with the smaller rocks.
An example of a project calculation
To calculate the amount of rock you will need for your project. First, measure the length and width of the area to be covered. For example, a square 10 ft by 10 ft would be 100 square feet. For gravel three inches thick, multiply your 100 square feet by .25 feet, for a total of 25 cubic feet.
We sell our rock by the cubic yard. To convert your 25 cubic feet into cubic yards, you must divide by 27. For our example of 25 cubic feet, this division gives us .92 cubic yards. Round this up to 1 cubic yard, and you are ready to order!
We are experts in calculating rock required for very difficult projects, please feel free to contact us for assistance.
Formulas for area calculations.
Area of a Rectangle or Square - Length times Width
Area of a Right Triangle - (Length times Width) divided by 2
Area of a Circle - (1/2 diameter times 1/2 diameter) times 3.14
Area of an Oval - (1/2 of Length) times (1/2 of Width) times 3.14
Rock Coverage Guide - One ton of rock will cover: | |
240 square feet | 1" deep |
120 square feet | 2" deep |
80 square feet | 3" deep |
60 square feet | 4" deep |
50 square feet | 5" deep |
40 square feet | 6" deep |
20 square feet | 12" deep |
Above approximate for rock up to 1 1/2" and sand, soils that are weighed. |