How Much Road Base for a 24x40 Parking Pad?
How much road base for a 24x40 parking pad is a quick volume problem. 960 square feet at 4 inches comes to 11.85 cubic yards. Road base usually weighs about 1.4 to 1.65 compacted tons per cubic yard, so plan on roughly 17.8 tons.
Volume and tonnage calculator →The math for a 24x40 parking pad
- Area: 24 × 40 = 960 sq ft.
- Depth in feet: 4 ÷ 12 = 0.333 ft.
- Cubic feet: 960 × 0.333 = 320.0 cu ft.
- Cubic yards: ÷ 27 = 11.85 yd³.
- Tons: × 1.5 = 17.8 tons.
The volume and tonnage calculator does this for any size.
Road base needed by depth
| Depth | Cubic yards | Tons (approx.) | Tons +10% |
|---|---|---|---|
| 4 in | 11.85 | 17.8 | 19.6 |
| 6 in | 17.78 | 26.7 | 29.3 |
| 8 in | 23.70 | 35.6 | 39.1 |
About road base
Road base (also called base rock, ABC, or Class 2 base in different states) is a graded mix of stone and fines made to compact into a load-bearing layer. Weight per yard is a planning number; the scale ticket at the yard is the real one.
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. 19.6 tons may take more than one 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.
When to choose road base
Works well for:
- Base under asphalt and concrete
- Gravel roads and drives
- Equipment and shed pads
Less suited to:
- Drainage layers
- Decorative surfaces
- Surfaces that will stay uncompacted
Quick reference numbers
- Per inch over 100 sq ft: about 0.46 tons of road base (0.31 cubic yards).
- Per inch over 1,000 sq ft: about 4.6 tons.
- Another size for comparison: a 10x20 area at 3 inches takes about 2.8 tons.
- Weight used here: about 1.5 tons per cubic yard.
Where estimates go wrong
- 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.
- Ordering exactly the math. Uneven ground and spillage nearly always need a little more than the flat calculation.
Questions people ask
How many tons of road base for a 24x40 parking pad?
About 17.8 tons at 4 inches deep, or 19.6 tons with 10 percent extra.
How many cubic yards is a 24x40 parking pad at 4 inches?
About 11.85 cubic yards.
How much does a cubic yard of road base weigh?
Usually around 1.4 to 1.65 compacted tons, depending on stone size, fines and moisture.
How deep should road base be for a parking pad?
The table above shows 4 to 8 inches. Shallower depths suit top dressing; deeper depths suit new installs and heavier use.
How many square feet is 24x40?
960 square feet.
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 a Ton of Gravel Cover? Depth Chart
- How Much Road Base for a 24x30 Parking Pad?
- How Much Road Base for a 24x36 Parking Pad?
As an Amazon Associate, AsphaltTons.com earns from qualifying purchases. Product links below are sponsored.