Work out the ready-mix concrete, or the cement and ballast to mix it yourself, plus Type 1, mesh, membrane, formwork, expansion joints and skip for a concrete drive.
150mm for cars. Increase to 200mm for heavy vehicles
Concrete slab thickness. 100mm for cars, 125–150mm for vans or heavier vehicles
Area × Type 1 depth (150mm by default) × 2,100 kg/m³ compacted, plus waste, rounded up to whole bulk bags.
Area × slab thickness is the volume of concrete. Ready-mix is ordered in 0.25 m³ steps, so we add waste and round up. For mixing by hand, dry materials take up about 54% more room than the finished concrete, so we multiply by 1.54 before splitting by the mix ratio.
A142 mesh sheets (4.8 × 2.4 m) lapped 200mm, a polythene DPM with 10% for laps, formwork board and pegs round the perimeter, and expansion joints about every 4 m along the drive.
The dig covers the Type 1 plus the slab. The skip is chosen by the volume of loosened soil and its weight.
These are estimates for ordering materials, not a structural design. Check site conditions, and anything unusual, with a qualified builder or engineer.
100mm of concrete on 150mm of Type 1 for cars. Make it 125–150mm if vans, motorhomes or delivery lorries will use it.
1:1.5:3 (cement : sand : gravel), roughly C20–C25, is a sensible minimum for a drive. If you're ordering ready-mix, ask for a paving mix such as PAV1, or C25 or stronger.
For more than about 1 m³, usually yes, once you count mixer hire and the time. A 42 m² drive at 100mm is about 75 bags of cement and 10 tonnes of ballast to mix by hand.
Mesh doesn't stop concrete cracking, but it holds the pieces together if it does. A142 is the usual choice for domestic drives, set in the middle of the slab on spacers.
Concrete expands and shrinks with temperature. Joints about every 4 m, and wherever the slab meets a wall, give it room to move so it doesn't crack in random places.