How to Calculate Gravel the Right Way
To estimate gravel correctly, you need three things:
- Square footage of your area
- Desired compacted thickness
- Material type (affects weight)
The Formula
Square feet × depth (in feet) ÷ 27 = cubic yards
Cubic yards × material density = tons
Cubic yards × material density = tons
Common Texas Examples
Residential Driveway Base
Area: 1,000 sq ft
Thickness: 4" compacted
Material: Crushed limestone
Density: 1.4 tons/yard
Total: ≈ 52 tons
Construction Entrance / Pad
Area: 2,000 sq ft
Thickness: 6" compacted
Material: Crushed concrete
Density: 1.45 tons/yard
Total: ≈ 125–135 tons
Material Density Reference (Texas Averages)
| Material | Tons per Cubic Yard |
|---|---|
| Crushed Limestone | 1.35 – 1.4 |
| Crushed Concrete | 1.4 – 1.5 |
| Pea Gravel | 1.3 |
| River Rock | 1.2 – 1.25 |
These ranges reflect what we see delivered in North Houston and Montgomery County — not lab-perfect numbers.
Compaction Matters More Than People Think
If you order based on loose depth and don't account for compaction, you'll be short. This is one of the most common mistakes we see on driveways and pads.
Rule of Thumb
4" compacted = ~5–5.5" loose
6" compacted = ~7–7.5" loose
6" compacted = ~7–7.5" loose
Local Tip (Houston Area)
Clay soils and rain mean underestimating material almost always costs more later. Ordering slightly heavy is cheaper than remobilizing a truck.