Gravel Driveway Separation

[Kirbs]

I'm laying a new gravel driveway. I've dug down and filled with Type 1 to a decent depth, and as per best practice started with a separation membrane underneath the Type 1. I've then compacted the Type 1 in layers.

For the most part the Type 1 has bound together to form a nice hard surface and I finished off with a bag of Grano Dust for the odd area where the Type 1 appeared to contain fewer 'fines'.

In spite of all this I'm worried about the gravel mixing with the Type 1 over time - I know the membrane should be below the Type 1 as I have done, but would there be any actual downside to another separation membrane between the Type 1 and the Gravel?

 

[jj4091]

I'm laying a new gravel driveway. I've dug down and filled with Type 1 to a decent depth, and as per best practice started with a separation membrane underneath the Type 1. I've then compacted the Type 1 in layers.

For the most part the Type 1 has bound together to form a nice hard surface and I finished off with a bag of Grano Dust for the odd area where the Type 1 appeared to contain fewer 'fines'.

In spite of all this I'm worried about the gravel mixing with the Type 1 over time - I know the membrane should be below the Type 1 as I have done, but would there be any actual downside to another separation membrane between the Type 1 and the Gravel?

I wouldn't have thought so as long as it is permiable

 

[scbk]

Just put down a fairly thin layer of gravel, the thicker it is, the harder to walk on/drag a bin across.
I wouldn't put a membrane between the stone, you don't need it, you want the gravel to bed in to the sub base a touch.

 

[Maatz123]

I've got a stone driveway with a type 1 sub base, as long as its well compacted it should never come lose and mix with the top layer