How much decomposed granite do I need?
Decomposed granite makes firm, natural looking paths, patios, and driveways in dry climates.
Enter the length, width, and depth of your area above. The calculator shows cubic yards, cubic feet, an estimated weight in tons, and the number of 0.5 cubic foot bags if you buy bagged decomposed granite. Add a price per cubic yard and it also estimates the cost.
Cubic yard calculator for decomposed granite
This cubic yard calculator for decomposed granite works for any shape. Pick rectangle for most beds and slabs, circle for round areas, or trench for narrow runs. Open the price estimator under the calculator to add your supplier price, delivery fee, and tax. For a full cost breakdown, see the decomposed granite cost calculator.
Decomposed Granite weight and bags per cubic yard
A planning value for decomposed granite is 2,700 pounds per cubic yard, which is 1.35 US tons. Moisture, particle size, and compaction move that number, so treat it as a starting point.
| Measure | Value |
|---|---|
| Pounds per cubic yard | 2,700 |
| US tons per cubic yard | 1.35 |
| Kilograms per cubic yard | 1,225 |
| Cubic yards per US ton | 0.74 |
| Cubic feet per US ton | 20.00 |
| 0.5 cubic foot bags per cubic yard | 54.0 |
How far does a cubic yard of decomposed granite go?
Coverage depends only on depth. The deeper the layer, the less area a cubic yard covers. The suggested depth for decomposed granite is 2 to 4 inches, and 3 inches is a common choice.
| Depth (inches) | Square feet covered | Square yards covered |
|---|---|---|
| 1 | 324 | 36.0 |
| 2 | 162 | 18.0 |
| 3 | 108 | 12.0 |
| 4 | 81 | 9.0 |
| 6 | 54 | 6.0 |
| 8 | 40 | 4.5 |
| 12 | 27 | 3.0 |
Decomposed Granite needed for common areas at 3 inches deep
| Area | Square feet | Cubic yards | US tons | 0.5 cubic foot bags |
|---|---|---|---|---|
| 5 by 5 ft | 25 | 0.23 | 0.31 | 13 |
| 8 by 10 ft | 80 | 0.74 | 1.00 | 40 |
| 10 by 10 ft | 100 | 0.93 | 1.25 | 50 |
| 10 by 20 ft | 200 | 1.85 | 2.50 | 100 |
| 12 by 12 ft | 144 | 1.33 | 1.80 | 72 |
| 15 by 20 ft | 300 | 2.78 | 3.75 | 150 |
| 20 by 20 ft | 400 | 3.70 | 5.00 | 200 |
| 20 by 30 ft | 600 | 5.56 | 7.50 | 300 |
| 30 by 40 ft | 1,200 | 11.11 | 15.00 | 600 |
| 50 by 50 ft | 2,500 | 23.15 | 31.25 | 1,250 |
Worked example: 30 by 4 feet at 3 inches
The area is 30 feet times 4 feet, or 120 square feet. A depth of 3 inches is 0.25 feet. Volume is 120 times 0.25, which is 30.00 cubic feet. Divide by 27 to get 1.11 cubic yards. At 2,700 pounds per cubic yard that weighs about 1.50 US tons. With 10 percent extra, order 1.22 cubic yards.
Tips for ordering decomposed granite
- Spread it in 2 inch layers and compact each one with a plate compactor or roller.
- Water lightly while compacting to help the fines bind.
- A stabilizer additive makes the surface harder and reduces dust.
Loose decomposed granite can wash out in heavy rain, so grade the surface for drainage.
Frequently asked questions
How many cubic yards of decomposed granite do I need?
Multiply length, width, and depth in feet, then divide by 27. A 30 by 4 foot area at 3 inches deep needs about 1.11 cubic yards.
How much does a cubic yard of decomposed granite weigh?
About 2,700 pounds, or 1.35 US tons, as a planning value. Ask your supplier for the exact figure.
How deep should decomposed granite be?
Most projects use 2 to 4 inches. 3 inches is a common choice.
How many square feet does a cubic yard of decomposed granite cover?
108 square feet at 3 inches deep, and 324 square feet at 1 inch.
How many bags of decomposed granite make a cubic yard?
About 54 bags of the 0.5 cubic foot size, which yields about 0.5 cubic feet each.