I am going to install laminate flooring in a basement in a century-old house. The basement currently has a wood plank floor. The planks look like some kind of soft wood, and are about six inches wide and random lengths.
My question is about the vapor barrier that I'll install below the laminate. Is it OK to install the barrier on top of the existing plank flooring, or do I need to rip up the planks? Obviously the former approach would be much less work, and it would give me a wood subfloor to work with, rather than the concrete that (I think) is under the planks. (I say "I think" because this could possibly be a dirt floor; I haven't been able to look very closely...and I definitely don't want to get into the business of installing a concrete floor in the event that there is only dirt under the planks currently.)
For what it's worth, the old plank flooring is currently in good shape, and does not show signs of moisture damage. I hope that means the moisture penetration in the basement is minimal, and I can get away with installing a vapor barrier on top of the existing floor without causing the planks to start rotting.