What membrane

[AnotherDesign]

I am going to have a driveway laid on a clay sub grade, with Marshalls Permeable Tegula Priora blocks.

In specifying a Geo-textile membrane under the sub base, which I presume must not be impermeable, as the water must finally drain away through the subgrade soil, what would be the ideal product to use? The website states " Only a genuine separation membrane should be used - not a " landscape fabric ", not a damp proof membrane, not a layer of polythene, ..... " But in the section "Do I need a Membrane? it is unclear what should be used.

Recommendations please.

Thanks

AnotherDesign

[Hotdog]

This should fit your requirements:
Terram T1000 Non Woven Geotextile Membrane