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Capillary Breaks

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An article on the web site for a vapor retarder manufacturer said something about putting a capillary break above the vapor retarder  - the capillary break being something like a layer of free draining gravel.
 
This is not the same as the endless ACI 302/360 discussion of a fill layer/base course above or below the vapor retarder,  it is somehow implying (I think) that sufficient moisture might come up through the vapor retarder that you need a capillary break on top of it.
 
I don't see how that can be true - I can see putting a capillary break below the vapor retarder, to prevent heaving right below the vapor retarder,  but it doesn't seem to make sense the other way around.
 
I asked the guy who wrote the article why anyone who do this,  and got this as a reply:
 
"It has been our experience and that of many of the contractors we work with that both ways work."
 
Does anyone have experience with a situation where it makes senses  to put a capillary layer above the vapor barrier? 
 
Gail Kelley