Calculate the bitumen or asphalt tonnage needed for a road, driveway, or car park. Enter the area dimensions, layer thickness, and mix type to get weight in tonnes.
The calculation converts area and thickness to volume, then multiplies by material density to get weight. A waste factor accounts for over-spray, trimming, and handling losses.
Density values used: Dense-grade 2.40 t/m³, Open-grade 2.20 t/m³, Mastic 2.30 t/m³, SMA 2.35 t/m³, Pure bitumen 1.04 t/m³. These are representative mid-range values. Ask your supplier for the specific density of their mix design.
Anyone involved in planning, tendering, or managing a paving or surfacing project.
Choose metric (metres and millimetres) or imperial (feet and inches). Thickness is always entered in mm or inches regardless of length units.
Measure the area to be paved. For irregular shapes, break the area into rectangles and run the calculator separately for each, then add the results.
This is the compacted depth of the bituminous layer. A typical road wearing course is 40 to 50 mm. A binder course is 60 to 80 mm. A full-depth pavement may use 100 mm or more.
Use 5% for straight runs on prepared sub-bases. Increase to 8 to 12% for irregular shapes or hand-laid repair work.
Select the mix type that matches your specification. Dense-grade HMA is the most common choice for driveways and roads. SMA is used for high-traffic surfaces.
The result shows total tonnes of mix, volume in m³, and the weight of bitumen binder content separately.
Tom is resurfacing a car park: 40 m long, 20 m wide, with a 50 mm dense-grade wearing course and a 5% waste allowance.
Layer thickness in this calculator is the compacted finished depth. Uncompacted loose material is typically 20 to 25% thicker. If you have a loose depth from a quote, multiply by 0.8 to get compacted equivalent.
Using 2.4 t/m³ for open-grade mix (which is closer to 2.2) overstates the material requirement. Always confirm the density with the mix design or your supplier's data sheet.
Calculating net volume only and ordering exactly that amount leaves no margin. Material lost to trimming, overspray, and handling typically adds 5 to 10% to the net requirement.
Entering 5 instead of 50 for a 50 mm layer produces a result that is 10 times too low. Always check units before placing a supplier order.
Licensed civil engineer with 16 years of pavement design and road construction experience. Tom has managed bituminous surfacing contracts across municipal and highway projects and has reviewed quantity take-off procedures for major paving contractors.
For a 50 mm wearing course over 1,000 m², dense-grade mix weighs roughly 120 tonnes. A standard articulated tipper carries 20 to 24 tonnes, so plan for 5 to 6 loads plus one partial load as contingency.