Slab on Grade Road Base
Slab on Grade Road Base
(OP)
Does anyone see any problems with using road base for a garage slab? Instead of sand or gravel.
The only issue that comes to mind, is the capillary break would be reduced.
The only issue that comes to mind, is the capillary break would be reduced.





RE: Slab on Grade Road Base
RE: Slab on Grade Road Base
They have to use road base for the drive and walk: so wouldn't it be easier to just deal with one material? Does seem trivial, but most of the stuff big or tiny typically does (in my limited experience).
I just figured forgo the sand forgo the gravel, use a vapor retarder if you want. Wam bam done.
RE: Slab on Grade Road Base
RE: Slab on Grade Road Base
RE: Slab on Grade Road Base
Personally my feelings about the "capillary" action is that it's generally false. Unless you have an extremely high GWT there won't be enough moisture where capillary action will have any effect. The purpose of the granular material is to get the top and bottom surface of the concrete to "dry" (I don't mean cure) about the same, so that the slab cures symmetrically and thus curls less; and also to allow the concrete to move a little more easily in the case of sand, to reduce shrinkage cracking; and lastly to provide base/foundation to the slab. My reasoning is that the water in the soil will condense on any impermeable barrier on top of the soil, it is water in a vapor state, not a liquid.
Say if I place two pieces of glass 2'x2' in the yard one with a layer of sand underneath the other directly on the earth. The supposition of the "capillary" theory is that the one placed on sand will not have water condense on it? Has anyone tried this?
Thanks all for the comments, and let me know if I'm mistaken or my reasoning went off kilter.