My wife is thinking to put a plastic vapor barrier over the dirt floor and to cover with rubber mats? 

@Paul SandhuYou could get them plastic pillow cases, so when they slobber in there sleep, they won't get tobacco stains on their pillows.

The modern composite materials IMO are 100% recycled plastic and there's little wood in it.

The modern composite materials IMO are 100% recycled plastic and there's little wood in it.

It definitely has a plastic look to it no matter how well you install it.

I’ve had the best luck with the plastic FRP Wall Boards secured directly to the concrete walls, French drain and sump pump.

The plastic line broke & the condensate ran down the 15 yr old cement poured basement wall & it literally spalled the cement 1/2inch deep. 

In order to do that you would still have to plastic off the whole room for 3-4days to do it right and run a negative air filtration system the whole time so their entire apt doesn't get covered in dust.

After this was done we put down 14mm plastic under the house as a moisture barrier.We dug a French drain around the front of the house back to the creek to help with any moisture issues under the house.While we were under the house we also replaced all the plumbing with brand new pipes.Both bathrooms have been completely renovated with the master getting a full custom tile shower and the other bathroom getting a soaker tub with custom tile surround.

He then had a different company come in to dig up the perimeter, AGAIN, to correct the weeping tile issues.The job is still not complete, in fact the siding is still missing with tattered plastic wrap barley holding back the snow, ice & rain.