Grano-dust for final finish ion sub base?

[R1chyo]

Hi there, has anyone spread a layer of grano-dust onto of the MoT Type 1 as the final layer before adding the aggregate finish of a gravel drive? Does this work well? Will it affect permeability? My builder used MoT that was too coarse I feel - so even after wacking there is a lot of chunky stuff poking through.. Thanks

[digerjones]

Yes thats good practice. Not sure how permeable it will be. Same as mot, not very permeable

[SureSet]

Type 3 would give the most permeability. Think the grano dust would make type 1 less permeable.