When undertaking landscaping or gardening projects, purchasing soil in bulk is often the most economical method. The standard unit of measurement used by suppliers for bulk materials like topsoil, compost, and mulch is the “yard.” Understanding this volumetric measure is the first step in accurately planning and budgeting for any project.
The Definition of a Cubic Yard of Soil
A “yard” of soil refers to one cubic yard, which is a volume defined as a cube measuring three feet wide, three feet long, and three feet high. This volume calculation yields twenty-seven cubic feet of material. The term is a convenient shorthand used by suppliers for materials like soil, gravel, and wood chips, which are sold by volume rather than weight.
To visualize the size of this quantity, consider that a typical residential wheelbarrow holds about two to three cubic feet of material. Therefore, one cubic yard of soil translates roughly to nine to fourteen full wheelbarrow loads. Knowing this conversion helps in assessing the physical effort required to move the bulk material.
How to Calculate Your Soil Needs
Determining the amount of soil required involves calculating the total volume of the area to be filled. The fundamental formula for volume is Length multiplied by Width multiplied by Depth (L x W x D). All dimensions must be in feet for the calculation to yield cubic feet.
A common challenge arises when the desired depth is measured in inches, such as four or six inches for a raised garden bed. To correctly integrate this into the formula, the depth in inches must be converted to feet by dividing the measurement by twelve. For instance, a depth of six inches is converted to 6 / 12 = 0.5 feet.
Once all three dimensions are in feet, the calculation provides the volume in cubic feet. For example, a garden bed measuring ten feet long by ten feet wide requiring a six-inch depth would be calculated as 10 ft x 10 ft x 0.5 ft, resulting in 50 cubic feet of volume.
To convert the required cubic feet into cubic yards, the total must be divided by twenty-seven, since there are twenty-seven cubic feet in one cubic yard. Continuing the example, 50 cubic feet divided by 27 equals approximately 1.85 cubic yards.
Practical Considerations for Ordering and Delivery
While calculations provide the exact volumetric need, real-world ordering requires considering the significant difference between volume and weight. The weight of a cubic yard of topsoil can vary dramatically based on its composition and, primarily, its moisture content. A dry cubic yard of topsoil may weigh around 2,000 to 2,200 pounds, but a saturated, wet yard can weigh up to 3,000 pounds or more.
This weight disparity is important for transportation logistics, especially if planning to haul the material yourself in a pickup truck, as vehicles have strict payload limits. Moreover, the type of soil matters; sandy soil tends to be heavier than soil with high organic matter, and wet clay soil can be among the heaviest.
Delivery logistics also require careful planning beyond the weight of the material. Bulk soil is typically delivered using a large dump truck, which needs clear and unobstructed access to the drop-off location. Driveway protection, such as laying down plywood, may be necessary to prevent damage from the weight of the heavy truck and the impact of the material being dumped.
Finally, soil settling, or compaction, is a predictable factor that should influence the final order size. When soil is spread, it contains many air pockets, and over time, particularly after watering and natural settling, the volume will reduce. It is common practice to order 10% to 15% more than the calculated volume to account for this natural compaction and ensure the desired final depth is achieved.