Calculating yards of soil is the process of determining the total volume of soil needed for a specific project, measured in cubic yards. This is a fundamental step in landscaping, gardening, construction, and any project involving earthmoving or soil replenishment. Accurate calculation prevents over-ordering (wasted money and effort) or under-ordering (project delays and incomplete work).
Who should use it? Anyone planning to:
Create new garden beds or flower patches.
Establish a new lawn from seed or sod.
Fill raised garden beds.
Grade or level an area of their yard.
Add soil to existing planting areas.
Use soil as a base for patios, walkways, or driveways.
Fill retaining walls or erosion control structures.
Common Misconceptions:
Soil doesn't compact: Many people assume the soil they buy is the final volume they'll have. In reality, soil settles significantly, especially when compacted by rain, foot traffic, or machinery. This calculator accounts for that.
Depth is always in feet: While length and width are typically measured in feet, soil depth is often specified in inches. It's crucial to convert inches to feet for accurate volume calculations.
"A yard" is always the same: The term "yard" can refer to a square yard (area) or a cubic yard (volume). For soil, we always mean cubic yards.
Soil Volume Formula and Mathematical Explanation
The core principle behind calculating soil volume is finding the area of the space and multiplying it by the desired depth. Since soil is typically sold by the cubic yard, we need to ensure all measurements are compatible and converted correctly.
This gives us the volume in cubic feet. To convert cubic feet to cubic yards, we divide by 27, as there are 27 cubic feet in one cubic yard (3 ft × 3 ft × 3 ft = 27 cu ft).
Loose Cubic Yards = Volume (Cubic Feet) / 27
However, soil settles after it's placed and compacted. The compaction factor accounts for this reduction in volume. A factor of 1.0 means no compaction, while lower factors (e.g., 0.75) indicate significant settling.
A multiplier representing how much the soil will settle.
Unitless
0.67 – 1.0
Cubic Feet
Intermediate volume calculation before yard conversion.
Cubic Feet (cu ft)
Calculated
Loose Cubic Yards
Volume of soil before compaction.
Cubic Yards (cu yd)
Calculated
Final Cubic Yards
Volume of soil after accounting for compaction. This is the amount to order.
Cubic Yards (cu yd)
Calculated
Practical Examples (Real-World Use Cases)
Example 1: Creating a New Lawn Area
Sarah wants to create a new lawn in her backyard. The area measures 30 feet long by 20 feet wide. She wants a soil depth of 4 inches to establish a healthy grass root system. She knows the soil will be lightly compacted by rain and walking.
Inputs:
Length: 30 ft
Width: 20 ft
Depth: 4 inches
Compaction Factor: 0.8 (Lightly compacted)
Calculation:
Area = 30 ft * 20 ft = 600 sq ft
Depth in feet = 4 inches / 12 = 0.333 ft
Cubic Feet = 600 sq ft * 0.333 ft = 200 cu ft
Loose Cubic Yards = 200 cu ft / 27 = 7.41 cu yd
Final Cubic Yards = 7.41 cu yd * 0.8 = 5.93 cu yd
Interpretation: Sarah needs approximately 5.93 cubic yards of soil. She should round up to 6 cubic yards when ordering to ensure she has enough, accounting for slight variations or spillage. This calculation helps her budget accurately for the soil delivery.
Example 2: Filling Raised Garden Beds
John is building two raised garden beds. Each bed is 8 feet long, 4 feet wide, and he wants to fill them to a depth of 12 inches. He's using a bagged soil mix that doesn't compact much, so he uses a factor of 0.95.
Inputs:
Length per bed: 8 ft
Width per bed: 4 ft
Depth: 12 inches
Number of beds: 2
Compaction Factor: 0.95 (Minimal compaction)
Calculation:
Area per bed = 8 ft * 4 ft = 32 sq ft
Total Area = 32 sq ft/bed * 2 beds = 64 sq ft
Depth in feet = 12 inches / 12 = 1 ft
Cubic Feet = 64 sq ft * 1 ft = 64 cu ft
Loose Cubic Yards = 64 cu ft / 27 = 2.37 cu yd
Final Cubic Yards = 2.37 cu yd * 0.95 = 2.25 cu yd
Interpretation: John needs about 2.25 cubic yards of soil for his raised beds. Ordering 2.5 cubic yards would be a safe bet. This ensures he has enough soil to fill both beds to the desired depth without running short.
How to Use This Soil Volume Calculator
Using this calculator is straightforward. Follow these simple steps to get your soil volume estimate:
Measure Your Area: Accurately measure the length and width of the space you need to fill with soil. Ensure your measurements are in feet.
Determine Desired Depth: Decide how deep the soil layer needs to be. This depends on your project (e.g., lawn, garden bed, base layer). Measure this depth in inches. Refer to the Soil Depth Guide for common recommendations.
Select Compaction Factor: Choose the appropriate compaction factor from the dropdown menu. This is crucial because soil settles. Use '1.0' for very loose, uncompacted material or '0.67' for heavily compacted soil. For most landscaping projects, a factor between 0.75 and 0.9 is suitable.
Click Calculate: Press the "Calculate Soil Yards" button.
Reading the Results:
Main Result (Total Yards): This is the final, recommended amount of soil to order in cubic yards, after accounting for compaction.
Cubic Feet: The raw volume calculation in cubic feet.
Cubic Yards (Loose): The volume before considering soil settling.
Cubic Yards (Final/Compacted): The adjusted volume, representing the actual amount needed after the soil settles.
Formula Explanation: Provides a clear breakdown of how the calculation was performed.
Decision-Making Guidance:
Always round your final calculated yardage up to the nearest half or full yard when ordering. It's better to have a little extra soil than to run short, which can be costly and inconvenient. Consider factors like spillage during transport or uneven ground when deciding your final order quantity.
Use the Copy Results button to easily share or save your calculated figures.
Key Factors That Affect Soil Volume Calculations
While the formula provides a solid estimate, several real-world factors can influence the actual amount of soil you need:
Soil Type and Composition: Different soils compact differently. Sandy soils tend to drain well but may not hold shape as much as clay-heavy soils. Organic matter content also affects compaction.
Compaction Method: How the soil is compacted matters. Heavy machinery will compact soil more than gentle raking or natural rainfall. The chosen compaction factor is an estimate; actual compaction can vary.
Moisture Content: Wet soil is heavier and can compact more easily than dry soil. The moisture level at the time of placement and compaction can affect the final volume.
Subgrade Preparation: The surface onto which you are adding soil can impact how much is needed. If the subgrade is uneven, you might need more soil to achieve a consistent depth. A well-prepared, level base requires less soil.
Settling Over Time: Even after initial compaction, soil can continue to settle slowly over months or years, especially with freeze-thaw cycles or repeated moisture saturation.
Waste and Spillage: During transport (especially from bulk delivery), loading, and spreading, some soil is inevitably lost due to spillage. Always factor in a small buffer for this.
Project Specifics: For critical applications like structural fills or retaining walls, engineers often specify exact soil types and compaction requirements, which may differ from standard landscaping needs.
Frequently Asked Questions (FAQ)
Q1: What is the difference between cubic feet and cubic yards?
A1: A cubic foot is a measure of volume equal to a cube with sides of 1 foot. A cubic yard is a measure of volume equal to a cube with sides of 3 feet. There are 27 cubic feet in 1 cubic yard (3x3x3=27).
Q2: Why is the "Final Cubic Yards" number lower than "Loose Cubic Yards"?
A2: This is because soil naturally settles and compacts after it is placed. The "Final Cubic Yards" figure accounts for this reduction in volume, giving you a more realistic amount to order.
Q3: How do I measure the depth of soil needed?
A3: Measure the desired thickness of the soil layer. For example, if you want 6 inches of topsoil for a garden bed, your depth is 6 inches. Always convert this to feet for calculations if your other measurements are in feet, or use the calculator's built-in conversion.
Q4: What if my area isn't a perfect rectangle?
A4: For irregular shapes, break the area down into smaller, regular shapes (rectangles, triangles). Calculate the volume for each section and sum them up. Alternatively, estimate the average length and width.
Q5: How much extra soil should I order?
A5: It's generally recommended to add 5-10% extra to your final calculated yardage to account for settling, spillage, and unevenness. Rounding up your final figure usually covers this.
Q6: Can I use this calculator for gravel or mulch?
A6: Yes, the basic volume calculation (Length x Width x Depth) applies to any material measured by volume. However, compaction factors for gravel or mulch might differ significantly from soil. Always check supplier recommendations.
Q7: Where can I find soil delivery services?
A7: Local landscaping supply companies, garden centers, and construction material providers often offer bulk soil delivery. Search online for "bulk soil delivery near me" or "landscaping supply yard".
Q8: What's the best way to ensure I order the right amount of soil?
A8: Double-check your measurements, use the compaction factor appropriate for your soil type and project, and always round up your final calculated volume. If unsure, consult with your soil supplier.