I have a two year old house that sits on an 8" concrete floating slab. The slab is insulated below and around the side. The floors in the house are unfinished. That is, the concrete slab is currently the floor.
To get some idea of whether there is moisture coming out of the slab, I taped a ~1'x1' sheet of plastic to a spot on the floor. When I removed it a couple weeks later there was no evidence of moisture either on the plastic or the slab itself.
I am looking at having finish flooring put in. I am considering linoleum (specifically, marmoleum click tiles). On an early site visit the installer seemed confident that a vapor barrier should be installed on the slab to keep the tiles dry.
Considering the details of this particular slab, is there reason to think the vapor barrier will be completely redundant? If the details are not sufficient, is there further information that can easily be gathered that would point to redundancy (or the opposite)?