Bought the house in 2013, and the basement was finished in the owens corning panel system, with carpeting laid over padding directly onto the concrete floor. The basement NEVER smelled of mold, the carpeting never felt damp, and with the built in Humidex system running, and a dehumidifier running 24/7, the humidity down there averages 45%.

That being said, we had 8" of water in the basement due to a freak historic rain storm back in august that dumped 14.27" of water on our town within a 3 hour period. We have french drains in the basement, and a high capacity sump with backup, which discharges directly to the city sewer system. However, when that much rain fell in that short of time, the city's sewer was completely filled and any bit of water being pumped out of the house, just came right back in. So the water being pumped out had nowhere to go but the basement. Literally every home in the entire community around us had water in the basement. So that being said, in the 15+ years prior to that, the basement had no flooding, and the carpeting was original (and old and ugly). So needless to say the basement rarely, if ever sees any kind of moisture.

Since the flooding the carpeting has come out, all the wall panels were dried out with commercial dehumidifiers running for 2 weeks straight, and a secondary outlet was installed for the sump pump to discharge to the street in the event of a sewer backup. So i'm not expecting any moisture problems ever again.

I'd like to put down some laminate down there, and i know laminate is always a no no from everyone, but i honestly dont see a problem seeing that the basement is consistently 45% humidity even in the dead of summer, and i havent seen a drop of moisture on the concrete floor. Is a vapor barrier really necessary in this case? Considering there was none for the 15+ years that the carpet was down there with no mold issues or moldy smell? I feel like a vapor barrier will only CAUSE moisture problems as it has nowhere to evaporate from. I would assume a good underlayment, and padded laminate should provide to be plenty.

Thoughts?

 

Doing anything other than following the mfgs installation instruction will obviously risk and warranty coverage if that is of any value. As you have learned, all basements are a hole in the ground with high probability that they will flood eventually. In addition, they all have to deal with moisture vapor unless extreme measures were taken when built.

The previous carpet apparently survived, but changing to laminate with or without a vb is not guaranteed.

What does the flooring mfg say?

Bud

 

So you don't need my second opinion, huh? Why not graduate at least to a click lock engineered flooring. It is wood rather than MDF with a picture of wood on it. It is a higher quality product, and , although it may not survive the next flood, it will be a better product that won't swell up when someone says "water".

 

#1, not even legal in most places to dump your sump pump into a town storm system.
Main reason is the exact case you posted.
Reroute it and never have that problem again.
Just not a big fan of laminate below grade, had to replace to much of it in above grade bathrooms, kitchens, and placing anything as simple as placing a dogs water bowl on the floor from a single water event.

 

May I suggest rubberized flooring?

 

Plain and simple, it's a risk. If anything goes wrong with the laminate, even if moisture has nothing to do with the problem, once you buy laminate and install it in a basement, there is no warranty. Even if it's defective, there is no warranty, period. If you can accept that, then go ahead.