“The terms vapor barrier or vapor retarder have a tendency ... Retarders Used in Contact with Soil or Granular Fill under Concrete Slabs) defines three classes of membranes: A, B and C.

Moisture is something to be managed. A vapor barrier can cut down on earthy smells, mildew, and general humidity.

If you're installing concrete slabs in a basement or another area of your home, you'll also need to install a vapor barrier to add protection. While not strictly required, you also need to add a ...

True vapor barriers should have a permeance rating ... thicknesses of at least 6 mils to be placed below on-ground concrete slabs. However, most conventional polyethylene materials typically ...