Formula
The formula to calculate asphalt volume is:
$$\text{Volume (ft³)} = \frac{\text{Length (ft)} \times \text{Width (ft)} \times \text{Thickness (in)}}{12}$$
We divide by 12 because thickness is measured in inches and we need to convert it to feet to match the length and width units.
Example Calculation
For a driveway with the following dimensions:
- Length: 15 feet
- Width: 10 feet
- Thickness: 3 inches
Volume calculation:
$$\text{Volume} = \frac{15 \times 10 \times 3}{12} = \frac{450}{12} = 37.5 \text{ ft³}$$
Understanding Asphalt Volume
Calculating the correct volume of asphalt is crucial for:
- Budget estimation - knowing how much material to order
- Project planning - scheduling delivery and application
- Avoiding waste - ordering too much asphalt
- Preventing delays - ordering too little asphalt
Common Asphalt Thicknesses
- Driveways: 2-3 inches for residential, 3-4 inches for heavy vehicles
- Parking lots: 3-4 inches minimum
- Roads: 4-6 inches or more depending on traffic
- Pathways: 2 inches minimum
Tips for Asphalt Projects
- Proper base preparation - Ensure a solid, compacted base before laying asphalt
- Order extra material - Add 5-10% to account for compaction and irregularities
- Consider weight - Asphalt weighs approximately 145 pounds per cubic foot
- Weather matters - Asphalt should be laid in warm, dry conditions for best results