We are going to put down commercial vinyl tile in our basement. It never floods but I do see an occasional damp spot on the slab, which is only about 2" thick (it's old). Do I need to apply a sealant before laying the tile? If so, which one would you recommend? Thanks!

None. Nor can I recommend VCT if you have any water problem such as you mentioned, water vapor will be too great just from what you state. You would be better off with something permeable.

john

 

You don't recommend it because the water vapor will unseat the tile? What would be better, something like ceramic?