How Much Gravel for a 18x40 Parking Pad?
How much gravel for a 18x40 parking pad is a quick volume problem. 720 square feet at 4 inches comes to 8.89 cubic yards. Gravel usually weighs about 1.3 to 1.5 tons per cubic yard, so plan on roughly 12.4 tons.
Volume and tonnage calculator →The math for a 18x40 parking pad
- Area: 18 × 40 = 720 sq ft.
- Depth in feet: 4 ÷ 12 = 0.333 ft.
- Cubic feet: 720 × 0.333 = 240.0 cu ft.
- Cubic yards: ÷ 27 = 8.89 yd³.
- Tons: × 1.4 = 12.4 tons.
The volume and tonnage calculator does this for any size.
Gravel needed by depth
| Depth | Cubic yards | Tons (approx.) | Tons +10% |
|---|---|---|---|
| 2 in | 4.44 | 6.2 | 6.8 |
| 3 in | 6.67 | 9.3 | 10.3 |
| 4 in | 8.89 | 12.4 | 13.7 |
| 6 in | 13.33 | 18.7 | 20.5 |
About gravel
Plain gravel is a loose term. Yards use it for rounded bank or river stone as well as for crushed rock, so ask whether the load is washed, crushed or a mix before you lock in a tonnage. Ask your supplier for their own tons-per-yard figure, since stone source and moisture shift it.
Preparing the parking pad
Dig out organic soil, compact the subgrade and set an edge so the stone does not migrate onto the lawn. A pad that holds parked weight for long periods benefits from a dense base under the surface stone. Since the parking pad carries parked vehicles, a little extra depth is cheap insurance.
Ordering tips
- Round up. Compaction and uneven ground eat material. Adding about 10 percent is common.
- Delivery size. 13.7 tons fits in a single typical dump truck load; small loads may carry a delivery fee. See how many tons of gravel in a dump truck.
- Bulk vs bags. At this size bulk delivery is usually the practical choice.
- Where it drops. Have the truck dump as close to the parking pad as firm ground allows.
Good and poor uses for gravel
Good uses:
- Rural driveways and lanes where low upfront cost matters
- Drainage areas and around downspouts
- Temporary access while a site is under construction
Poor fit for:
- Steep slopes, where loose stone washes downhill
- Spots plowed often, since plows push gravel into the lawn
- Areas next to doors, because stone tracks inside
Quick reference numbers
- Per inch over 100 sq ft: about 0.43 tons of gravel (0.31 cubic yards).
- Per inch over 1,000 sq ft: about 4.3 tons.
- Another size for comparison: a 20x25 area at 3 inches takes about 6.5 tons.
- Weight used here: about 1.4 tons per cubic yard.
Where estimates go wrong
- Ignoring the base. A thin surface layer over soft soil fails early no matter how much material is on top.
- Assuming every supplier uses the same weight. Two yards selling the same product name can quote different tons per yard.
- Measuring only the main rectangle. Aprons, turnouts and curved edges add real square footage.
- 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 tons of gravel for a 18x40 parking pad?
About 12.4 tons at 4 inches deep, or 13.7 tons with 10 percent extra.
How many cubic yards is a 18x40 parking pad at 4 inches?
About 8.89 cubic yards.
How much does a cubic yard of gravel weigh?
Usually around 1.3 to 1.5 tons, depending on stone size, fines and moisture.
How deep should gravel be for a parking pad?
The table above shows 2 to 6 inches. Shallower depths suit top dressing; deeper depths suit new installs and heavier use.
How many square feet is 18x40?
720 square feet.
Related guides
- How Much Does a Ton of Gravel Cover? Depth Chart
- Tons to Cubic Yards for Gravel: Conversion Chart
- How Many Tons of Gravel in a Dump Truck? Loads and Coverage
- How Much Gravel for a 18x30 Parking Pad?
- How Much Gravel for a 18x36 Parking Pad?
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