The concrete pavement comprises the actual slab and its foundation known as the ‘Subgrade’
A lot of concreters will say a concrete slabs don’t need any foundations……That’s Bulldust!
The area around your new home is likely to have had service trenches dug across it and be churned up by construction activity, which is not going to provide a strong enough base.
Basically you need to get rid of all unsuitable (soft) material including topsoil.
It needs to be replaced with a minimum of 100mm of suitable subgrade material such as roadbase.
See Preparing the Base for more information,
Here are some recommendations for the minimum concrete slab thickness:
- 75mm – Paths and Patios
- 100mm – Parking for Cars, Caravans and Utes
- 150mm – Footpath Crossover and Main Driveway
The reason why I suggest 150mm for the main driveway is because this has the biggest risk of something like a delivery truck using it.
For another post on on getting your paths and driveways correct see Concreting