How Much Tarmac Do I Need?
Multiply the area in square metres by the compacted depth in metres, then by 2.32. A 50 m² driveway at 50 mm needs about 5.8 tonnes, or 6.4 tonnes with a 10% buffer.
The short answer
Multiply the area in square metres by the compacted depth in metres, then by 2.32. A 50 m² driveway at 50 mm needs about 5.8 tonnes, or 6.4 tonnes with a 10% buffer.
Tarmac and asphalt are the same thing
"Tarmac" is a British colloquialism derived from tarmacadam, an early bitumen-bound macadam surfacing. It is also a registered company name. The material actually laid on UK driveways and roads today is asphalt concrete to BS EN 13108, the same family used worldwide. If you search for asphalt calculations you will find the same arithmetic.
Tonnage for common UK driveway sizes
| Driveway | Area | 50 mm | 60 mm | 80 mm |
|---|---|---|---|---|
| Small | 25 m² | 2.9 t | 3.5 t | 4.6 t |
| Single car | 35 m² | 4.1 t | 4.9 t | 6.5 t |
| Standard | 50 m² | 5.8 t | 7.0 t | 9.3 t |
| Two car | 70 m² | 8.1 t | 9.8 t | 13.0 t |
| Large | 100 m² | 11.6 t | 13.9 t | 18.6 t |
| Long drive | 150 m² | 17.4 t | 20.9 t | 27.9 t |
| Courtyard | 200 m² | 23.2 t | 27.9 t | 37.2 t |
Typical UK depths
A domestic driveway is usually laid as a 50–60 mm binder course with a 20–25 mm surface course over 100–150 mm of Type 1 sub-base. Some contractors lay a single 50 mm course on smaller drives. Commercial and adopted roads follow the Specification for Highway Works with considerably heavier sections.
UK pricing
Tarmac material runs roughly £65–£110 per tonne delivered in 2026, and installed driveway costs are typically £45–£90 per m² depending on region, access and how much excavation is needed. London and the South East sit at the top of that range.
Calculate it yourself
Related calculators and guides
Tonnage calculator
Full project tonnage.
Price per ton
2026 pricing.
How to calculate
The method in full.