How Much Does 21 Tons of Decomposed Granite Cover?
How much does 21 tons of decomposed granite cover depends on how deep you spread it. At about 1.35 tons per cubic yard, 21 tons is roughly 15.6 cubic yards. Spread 3 inches deep, that covers about 1,680 square feet. Every added inch of depth cuts the coverage noticeably.
Volume and tonnage calculator →How the coverage is figured
- Tons to cubic yards: 21 ÷ 1.35 = 15.6 yd³.
- Cubic yards to cubic feet: × 27 = 420 cu ft.
- Divide by depth in feet: at 3 inches (0.250 ft), 420 ÷ 0.250 = 1,680 sq ft.
Coverage of 21 tons at different depths
| Depth | Square feet covered | Square yards |
|---|---|---|
| 2 in | 2,520 | 280 |
| 3 in | 1,680 | 187 |
| 4 in | 1,260 | 140 |
About decomposed granite
Decomposed granite (DG) is weathered granite broken into small particles and fines. It packs into a firm, natural-looking path surface, and stabilized versions include a binder. Weight runs about 1.25 to 1.45 tons per cubic yard, so treat the table as a planning range rather than an exact figure.
What 21 tons looks like on site
21 tons will usually take two or more truck loads, though legal limits vary by truck and state. Spread from the pile with a loader, skid steer or wheelbarrow, then rake to depth before compacting if the material calls for it.
- Check depth as you go. Stakes marked at the target depth help keep the spread even.
- Expect some loss. Compaction and uneven ground use more than the flat-math figure. Keep about 10 percent in reserve.
- Ask about moisture. Wet material weighs more, so a ton of it covers less.
To run your own numbers, use the volume and tonnage calculator.
Good and poor uses for decomposed granite
Good uses:
- Garden paths and patios with a natural look
- Around trees and in xeriscape designs
- Stabilized DG for accessible paths
Poor fit for:
- Steep grades without a stabilizer
- Areas right outside doors, since fines track in
- Driveways with heavy turning traffic
Quick reference numbers
- Per inch over 100 sq ft: about 0.42 tons of decomposed granite (0.31 cubic yards).
- Per inch over 1,000 sq ft: about 4.2 tons.
- Another size for comparison: a 20x25 area at 3 inches takes about 6.3 tons.
- Weight used here: about 1.35 tons per cubic yard.
Common estimating mistakes
- Skipping drainage. Water sitting under any surface softens the base and leads to ruts and potholes.
- Measuring only the main rectangle. Aprons, turnouts and curved edges add real square footage.
- Mixing up cubic yards and tons. Yards are volume, tons are weight; convert with the product’s weight per yard.
- Using inches as if they were feet. Depth has to be divided by 12 before you multiply; skipping that step inflates the order twelvefold.
Questions people ask
How many cubic yards is 21 tons of decomposed granite?
About 15.6 cubic yards at 1.35 tons per yard.
How many square feet does 21 tons of decomposed granite cover at 3 inches?
About 1,680 square feet.
How many square feet does 21 tons cover at 2 inches?
About 2,520 square feet.
How much does a yard of decomposed granite weigh?
About 1.25 to 1.45 tons.
Will 21 tons fit in one truck?
It depends on the truck. Single-axle dump trucks often carry under 10 tons and tandems around 13 to 16; your supplier will know their limits.
Related guides
- Crushed Stone vs Gravel: Differences and Best Uses
- Tons to Cubic Yards for Gravel: Conversion Chart
- How Many Tons of Gravel in a Dump Truck? Loads and Coverage
- How Much Does 19 Tons of Decomposed Granite Cover?
- How Much Does 20 Tons of Decomposed Granite Cover?
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