Professional Bitumen & Asphalt Calculator
Calculation Results
How to Calculate Bitumen and Asphalt Requirements
Planning a paving project requires precise calculations to ensure you order the correct amount of material. Whether you are surfacing a driveway, a parking lot, or a highway, the "Bitumen Calculator" helps determine the total tonnage of asphalt mix and the specific volume of bitumen binder required.
The Core Formula
The calculation for asphalt tonnage follows a standard physical volume-to-weight formula:
- Volume (m³) = Length (m) × Width (m) × [Thickness (mm) / 1000]
- Total Weight (Tonnes) = Volume (m³) × Density (kg/m³) / 1000
For most standard hot-mix asphalt (HMA) projects, a density of 2,300 to 2,450 kg/m³ is used as the industry standard. Our calculator uses 2,350 kg/m³ as a default value.
Understanding Bitumen Content
Bitumen is the black, sticky binder that holds the aggregate (stones and sand) together. Typically, asphalt mixtures contain between 4% and 6% bitumen by weight. If your project specifications require a 5% bitumen content, the calculator will isolate exactly how many tonnes of pure bitumen binder are needed within the total mix weight.
Example Calculation
If you have a driveway that is 20 meters long, 4 meters wide, and you want a thickness of 50mm:
- Area: 20m × 4m = 80 m²
- Volume: 80 m² × 0.050m = 4.0 m³
- Weight: 4.0 m³ × 2,350 kg/m³ = 9,400 kg (9.4 Tonnes)
- Bitumen (at 5%): 9.4 Tonnes × 0.05 = 0.47 Tonnes of binder.
Factors Affecting Your Estimation
It is important to remember that real-world conditions may vary. You should always account for a 5-10% wastage factor to cover surface irregularities, compaction variations, and minor spills during the paving process. Additionally, the density may change based on the type of aggregate used (basalt, limestone, or granite).