There are several reasons why you might need to lay a concrete pad in your garden. You could be creating off-road parking or erecting a garden shed. Each situation will require a different thickness pad, and whilst you could just lay all pads 200mm thick just to be safe, this is a waste of time and money if you only need to stand a shed on it.
With any concrete pad, you will also need to put down a sub-base of hardcore to absorb the ground movement and reduce the effect weight will have on the pad. Before you put down the hardcore, make sure the soil below is compacted firmly. If your soil is clay or peat, increase the depths shown below by around 50%.
Pathways
Normal paths through your garden, with low to medium foot traffic.
Concrete = 75mm
Sub-base = Not needed
Light structures
Garden sheds, etc.
Concrete = 75mm
Sub-base = 75mm
Patios
Concrete = 100mm
Sub-base = 100mm
Parking Spaces
Hard standing for a single car.
Concrete = 100mm
Sub-base = 100mm
Driveways
To support up to small vans.
Concrete = 150mm
Sub-base = 100mm
Garages
Concrete = 100mm (edges = 200mm)
Sub-base = 100mm
