The Brew Cabin

I currently have a concrete driveway, which is approx 20 yrs old, which I am thinking of paving over the top of. The concrete is sound, (I've had several skips full of land and conrete on it), but is old and weathered. I was looking drilling drainage holes in the concrete and then putting down a base of sand over the top of the concrete and paving over the top with some paving flags, possibly the Marshalls patio paving flags (Heritage I think) and pointing between them. I would also be leaving a 100mm gap between the house wall and the paving to filled with decorative gravel so this does not affect the DPC. Are these paving flags Ok for a driveway with frequent vehicle overrun?

Well, they are and they aren't. They can be used on a driveway, but they need to be bedded onto concrete, as, being only 40mm thick wet-cast products, they are NOT strong enough to take the weight of a car if laid on an unbound bed, such as sand.

So, if they are laid on concrete or mortar over the existing concrete, the rigid bedding makes them just about strong enough to take low speed traffic from family cars and small vans. However, as wet-cast concrete with a decorative riven effect, they wear relatively quickly compared to a pressed concrete paver such as BS Flags or Block Pavers, and with the typical driveway layout, where you're tracking up and down the same strip day in and day out, they wear even faster, creating two stripes of exposed concrete where the decorative texturing/moulding has been eroded by the regular trafficking.

Given the cost of these flags, I'd strongly recommend you look to use a pressed alternative, such as the Drivesett or Driveline, and use the existing concrete driveway as a 'sub-base'. Using a 50mm thick paver on a 40mm bed of sand builds up the paving level about the same as a 40mm wet-cast patio flag and a 40mm bed of concrete/mortar, so there's nowt lost in that respect, but the pavers tend to be slightly cheaper per square metre than the better quality patio flags.