Topsoil Volume Calculator
Results:
Cubic Yards Needed: 0 yd³
Cubic Feet Needed: 0 ft³
Standard 40lb Bags (0.75 cu ft): 0
Large 1 cu ft Bags: 0
Estimated Total Cost: $0.00
How to Calculate How Much Topsoil I Need
Whether you are starting a new garden bed, leveling your lawn, or filling a raised planter, knowing exactly how much topsoil to order is crucial. Ordering too little leads to mid-project hardware store runs, while ordering too much leaves you with a massive pile of dirt in your driveway. This guide will teach you the precise math to calculate topsoil volume.
The Standard Topsoil Formula
Topsoil is generally sold in Cubic Yards for bulk deliveries or Cubic Feet for bagged products. To calculate the volume, you need three measurements: Length, Width, and Depth.
The mathematical formula is:
- Volume in Cubic Feet = Length (ft) × Width (ft) × Depth (ft)
- Volume in Cubic Yards = Total Cubic Feet ÷ 27
Step-by-Step Calculation Example
Let's say you have a garden bed that is 20 feet long and 10 feet wide, and you want to add 4 inches of fresh topsoil.
- Measure dimensions in feet: Length = 20 ft, Width = 10 ft.
- Convert depth to feet: Since there are 12 inches in a foot, 4 inches is 4/12, which is 0.333 feet.
- Calculate Cubic Feet: 20 × 10 × 0.333 = 66.67 cubic feet.
- Convert to Cubic Yards: 66.67 ÷ 27 = 2.47 cubic yards.
In this scenario, you would likely order 2.5 cubic yards from a local supplier.
Bulk Topsoil vs. Bagged Topsoil
How you buy your soil depends on the scale of your project:
- Bulk (Cubic Yards): Best for projects requiring more than 1 cubic yard (roughly 27-54 bags). It is significantly cheaper but requires a delivery fee and a place to dump the soil.
- Bags (Cubic Feet): Best for small raised beds or touching up lawn patches. Most standard bags are 0.75 cubic feet or 1 cubic foot. If you need 10 cubic feet, you would buy 10-14 bags depending on the bag size.
Common Depth Recommendations
Not every project requires the same amount of soil depth. Here are some industry standards:
- Lawns (Top Dressing): 0.25 to 0.5 inches.
- New Lawns (Seeding): 4 to 6 inches.
- Flower Beds/Gardens: 6 to 12 inches.
- Raised Vegetable Beds: 12 to 18 inches (often mixed with compost).
Important Tips for Your Soil Order
1. The Settling Factor: Fresh topsoil is fluffy. Once it is watered and sits for a few weeks, it will settle and compress. Always order about 10% more than your exact calculation to account for this compaction.
2. Delivery Access: If ordering in bulk, ensure the delivery truck has a clear path to the drop-off point. A single cubic yard of topsoil can weigh between 1,500 and 2,200 pounds depending on moisture content.
3. Soil Quality: When buying topsoil, ask if it is "screened." Screened topsoil has been passed through a mesh to remove large rocks, roots, and debris, making it much easier to work with in a garden setting.