Volume, tonnage and truckloads for any layer of a driveway, path or parking lot.
The asphalt you drive on. The top layer, laid last and rolled. Typically 50 mm.
How deep the layer is once rolled — the depth on the finished job, not the loose depth off the truck. Do not add anything for roll-down; the tonnage already allows for it.
Hot and warm mix are the normal choice. Cold mix is for patching.
Extra to order for spillage and uneven subgrade. 5% is typical.
Nothing to work out yet
Enter values for Length, Width, Compacted Thickness, Truck Capacity (tonnes).
A driveway is built in layers, and this prices whichever one you are ordering. The surface course is the asphalt you drive on. Under it the base course, crushed stone that carries the load and spreads it out. Under that the sub-base, coarser stone doing the same job over a wider footprint. At the bottom is the subgrade — the ground that was already there. Subgrade is not in the layer list because you do not order it: it is prepared, not delivered. For the three you do buy, length × width × compacted thickness gives the volume in place, plus your waste factor — measure to the thickness you are laying to, not the loose depth before rolling. That volume becomes weight at the density of that material: asphalt by the mix you select, base course and sub-base at a nominal 2.1 t/m³ for compacted crushed stone, which is worth checking against your supplier's ticket. Truckloads are the tonnage divided by your truck capacity and rounded up, because a part load still books a whole truck. Coverage per load tells you how much surface one truck lays at that thickness.
Thirty square metres of surface course at 50 mm compacted, hot mix, with a 20 tonne truck. The calculator returns 1.5 m³ in place, 3.65 tonnes, one truckload, and tells you that one load covers 164 m² at this thickness.
That last figure is the sanity check. If your job is 400 m² and a load covers 164, you need three deliveries and you can plan where each one goes before it arrives. Asphalt cannot wait — it cools, and a load that sits is a load that is wasted.
The tonnage comes from a compacted density of 2.43 t/m³ for hot or warm mix. Warm mix shares hot mix's density because it is the same aggregate and binder laid at a lower temperature; cold mix genuinely carries more voids and weighs about 2.20.
Adding a compaction allowance. Asphalt is bought by weight, and compaction changes volume, not weight — a tonne is a tonne whether it is loose in the truck or rolled flat on your drive. The density used here is already the compacted density, so compacted volume times compacted density is the whole answer.
Add a further 15 or 20 percent "for compaction" on top and you have counted the same effect twice. On a large job that is an entire extra truckload with nowhere to go, and asphalt cannot be stored or returned. The other half of the same mistake is entering the loose depth off the truck instead of the finished depth after rolling. Measure what you want to end up with.
Tonnes, the mix type, and the number of loads you want. Truck capacity is a field here rather than a constant because it is the one number your haulier will tell you: 10 t rigid, 20 t six-wheeler, 30 t artic.
Pick the right layer first. This page prices whichever of the three you select — the asphalt surface course, or the crushed stone base course and sub-base beneath it, at a nominal 2.1 t/m³. It will not quote you subgrade, because subgrade is the ground that was already there. You prepare it; nobody delivers it.
The weight row names the material and the density it used, so both assumptions are on screen. The 2.1 t/m³ for crushed stone in particular is worth checking against your own delivery ticket — it moves with the quarry, and every source that publishes that figure says the same.
The drawing beside the form shows all four pavement layers with the one you are pricing picked out, and the thickness dimension sits on that layer alone. If the highlighted band is not the one you are ordering, the dropdown is wrong before the arithmetic ever gets a chance to be.