Concrete absorbs and retains water and the moisture can seep into the carpet padding and then into the carpet.
Carpet over concrete moisture.
Installing carpet over a basement concrete cement floor can be a simple project and requires very few tools to accomplish.
Another part of the basement we have a vinyl floor product that interlocks without grout not sure if it was glued with no issues.
The solution which you already alluded to would be to install 3 4 1 of eps over the slab held down with a subfloor tapconned to the slab.
The floor outside the bathroom walls is either carpet or bare concrete neither have moisture.
When checking concrete moisture the best solution to get readings of moisture deep in the slab is to use the astm f 2170 standard.
Any kind of persistent moisture will allow mold to get a foothold and soon ruin carpet or wood flooring.
Choosing the right carpet.
With an insulating carpet above the slab the slab temperature can be low enough to create a mold problem at the deeper levels of the carpet.
Carpeting over concrete floors can be a quick affordable and smart way to warm up a cool room reduce noise in your workplace and turn a bland and uninspiring space into somewhere warm and inviting.
Many carpets and carpet padding are vapor permeable so if your concrete basement is showing moisture it can continue to evaporate up through the pad and carpet.
For below grade slabs assume that the concrete floor will get damp at some point.
You then have two options depending on your circumstances.
Seal the floor either chemically or via membranes this creates an impermeable barrier between the sub floor and your flooring which means moisture cannot penetrate into your flooring.
Moisture barriers as the name implies set up a protective barrier to block moisture from reaching the pad and the carpet.
Over time hydrostatic pressure will force that moisture upwards and can cause bubbles in surface treatments and cracks in covering materials that are installed above it.
This task can be simple but it does require planning patience and the right tools.
They look similar to carpet padding but they have a plastic film on the surface to block moisture.
And both of the options use the same layers of 1 2 in.
However moisture levels can and do fluctuate over time so your sub floor moisture measurements may give you a false sense of security.
If excess moisture is present in a concrete slab when an impermeable surface treatment is installed it will become trapped under that covering.