[RedBeansMonday]

New to the site. Pulling up laminate flooring. Under the laminate is a plastic sheeting vapor barrier. Under the vapor barrier is old 12x12 glue down tiles circa late 1960’s. It is visibly wet under the vapor barrier and under the files. We live in the South. Is this normal condensation on the concrete slab? Or do I have a bigger problem? All thoughts welcomed appreciated.

 

[Nealtw]

If the slab does not have sheet poly under it or well drained gravel, moisture coming up under the slab can and will wick thru. That is why you had the poly there to protect the flooring , but no one ever says where that water should go.

 

[SeniorSitizen]

It's normal if the concrete temperature reaches a temperature below dew point temperature. You outdoor side walk of concrete may have the same symptoms on a cool morning when the surface cools below dew point temperature. After you remove that plastic that shouldn't have ever been there, it's time to do some concrete surface temperature and dew point temperature monitoring to know which direction to take.


EDIT EDIT : We have concrete floors plus basement concrete ( carpeted ) with sheet vinyl and carpet ( ground floor ) without those problems in 37 years. Nothing under concrete except original soil.