This is a really old thread, but for anyone that finds this (like me), let me share my recent experience. We had an unfinished basement for 10 years. Over those years, we had seepage through the walls due to improper drainage outside (this was a brand new house). I agree with the poster above that suggests you fix your landscaping. We had spots where water was pooling, and water just...finds a way. It's what it does. Anyway, also during that time, I worked down in the basement on top of some old carpet and pad that we tore out of a room we put hardwood floors in. Never had any issue with that just sitting on the floor. We recently had our third child, and decided it was time to finish the basement. We decided that we would waterproof the north side of the house that had most of the water seepage in the past. For the flooring, we put down linoleum in the bathroom, laminate in my office, and carpet in the main part of the basement where the kids would play. Lowe's sold us on the VERY BEST (their words) carpet pad for basements. It's this newfangled crap that has a "breathable" vapor barrier. So water can escape from underneath but not penetrate through it from above. That's the claim. Well, fast forward LESS THAN ONE YEAR... The whole area where that carpet is smells musty and gross. If you are going to use a pad, DO NOT, PLEASE, GOD, DO NOT buy anything with a vapor barrier on it, even if they swear it is breathable. It may be breathable, but not enough. The crappy 6 pound rebond stuff I had sitting down there for probably 7 years never did this. The moisture from your floor needs to be able to escape, not get trapped underneath there. Lowe's is now sending out somebody to look at it, and they will decide how to handle this problem. It is going to be a huge nightmare. Even if they are super cooperative, and offer to replace everything, I still have to move all of our stuff out of there, have it all tore up, clean up whatever mess is there properly (somehow I don't think Lowe's will do this part for me), and then get it reinstalled again. From other things I have read, if you are going to put anything over top of the concrete, you shouldn't try to seal it. Walls are one thing, especially if you have functioning drain tiles that will drain the water that has nowhere to go. I'd be interested to know if anyone has opinions on the laminate I put down in my office. Underneath that is the foil covered pad, which is...a vapor barrier.. Every video you watch on the internet says this is how it's done in basements. I get stopping the vapor from hitting the laminate, but worry now that it's just trapped and will try to creep up the walls. Home ownership is so much fun!

Anyone ever use Max Tile (interlocking vinyl tiles) or (allegedly) waterproof interlocking carpet tiles for a basement with flooding potential? Any feedback? Other suggestions? We are redoing a basement and put in a french drain and new sump pump to avoid flooding... but before pump was plugged in, we were hit with heavy rains and there was major flooding. Pump should work in the future, but just to be safe, want to put in flooring that is waterproof/resistant. Plan to use basement as play room so I am hesitant to use concrete/tile flooring which may be too hard. Thanks.

Sorry, but without the use of an appropriate underlay, carpet is a poor choice for a basement. There are just too many sources of moisture. Even if bulk water is under control, the cold concrete is the perfect surface for condensation when warm damp air comes in contact with it. As well, there is always a moisture drive upwards from the high pressure under the floor to the lower pressure in the air above. Appropriate carpet underlayments include: Dri-Core or competitive products; Delta FL or its competitors followed by OSB or plywood; and extruded polystyrene followed by OSB or plywood, as shown by Building Science Corp.

The DriCore R+ is closed cell STYROFOAM with OSB mounted on top. I can tell you that it is the vapour barrier system that DriCore produces for situations like yours. Your description makes it sound like the styrofoam was a jerryrigged system that mimics the DriCore R+ system. If the screws PIERCED the styrofoam and PIERCED the VAPOUR barrier, you essentially had a bunch of holes punched in the water-proofing system. The holes = water intrusion. And NO....LVT products do NOT LIKE underpad. That's why I'm suggesting going with a system that ADDS an R value. DMX has very little R-value. It is about the same as plywood. And just in case I misunderstood your post and there were NO HOLES IN THE VAPOUR BARRIER on the slab, then you have a MUCH BIGGER ISSUE than you anticipate. The stains on the DRYWALL is the big red flag here. And if you want an underpad, the DMX REQUIRES PLYWOOD to be placed over top! Yep. It says it in the very fine print of the INSTALLATION instructions. And to put the plywood on top....you need to SCREW IT DOWN onto the concrete!!! You need tapcons. And you need to the right drill bit, etc. And the DMX is HARD to "shim". You still need to get this floor flat enough for the LVT. Whew. DriCore R+ is SOOOOOOOO much more appropriate. The stains on the drywall concern me.