We have a 30 sq metre terrace that for the last 30 years has been paved with 600 x 600 x 50 pink and grey concrete slabs. The area is going to have facelift this summer and we are thinking about a new surface of Bradstone textured slabs.
The question is should we lay them over the existing slabs, which are stable and reasonably level or is it really necessary to lift them? I appreciate the need for the new slabs to stay below the dpc and air bricks.
If it is OK will a bed of sharp sand suffice or is mortar necessary under these circumstances?