This was probably beated to death hear already, but I still cannot collect all the pieces of this, so I thought I might ask. If you'd be so kind to share your knowledge...
So, we have this house, which is on a slab. The floor is Berber carpet all over (except the kitchen), and I believe it is on plywood put onto the slab (not sure if there's any vapor barrier under the plywood).
What we'd like to do is to put some laminate in the dining room and in the hall, so that the carpet doesn't get stained from food and dirt (kids!) My wife really likes the idea and pushes me forward, but I'm a little bit reluctant -- don't want to screw up. I'd like to DIY (or DIM).
So, here're my questions. From what I gathered, I need to put some vapor barrier on the concrete. OK so far, but what about the plywood which is already there? Should I remove it, or could I put it under the laminate flooring? What are the potential dangers of having that plywood there? I'd like to keep it -- it will add some insulation, it will make the floor more even (I'm not sure about flatness of the slab underneeth). Is there going to be a problem? Would it invalidate warranty? Also, the special foam underlayment -- do I put it over or under the plywood?
Second, I'm looking at different laminate options, and they seem to differ in thickness and warranties. Is the cheaper stuff (like the one in Costco -- for some $1.49/sq.foot) really a crap? How much difference does it make to use the more expansive quality stuff? This is not going to be commercial usage, just to be able to wet-moap it occasionally.
Also, I'm a bit concerned that laminate floor on a slab will feel cold. Is this going to be a factor?