If you are working on a large-scale landscaping project and find that you need to add soil to an area, you may wonder how you determine the amount you will need to buy. There are online calculators, or your local landscape-materials retailer can calculate the amount for you. You can also do it yourself by using a simple formula.
To manually calculate your soil needs, use the following formula: Length multiplied by width multiplied by depth in feet, divided by 27 equals yardage. Multiply the yardage by 1.2 because you will need extra material for compacting.
For example, let's say you have a spot to be filled that is 4 feet by 3 feet and you want the soil to be 3 inches deep. Three inches is 1/4 of a foot, so you would write this equation: 4 X 3 X 1/4 = 3. Divide this by 27 to get 0.11 cubic yards. To account for compaction, multiply 0.11 by 1.2 to get 0.132. You will need 0.132 cubic yards of soil for your needs.
If you have odd-shaped areas to fill, go to www.areamulchandsoils.com for an online calculator that will determine your needs.