A number of other firms use concrete sub-bases to save costs.  Here you can see one installed by a well-known firm in the Coleraine area.  The problems with using concrete are:

• It absorbs water which, when cold, freezes and cracks the sub-base

• It is easily damaged by strimmers or mowers

• It is harder to clean than granite and looks second-rate

We only ever use Mourne granite for our sub-bases for these reasons.  We have found that:

• Granite is much easier kept clean and maintained than concrete

• Granite is impervious to the frost

• Our sub-bases are not damaged by strimmers or mowers