Concrete floor question (To tile or not to tile...)

[bleedingheart]

Okay....we put cheap vinyl flooring over our concrete years ago..a quick fix to replace the old tile that was hideous...

So...it starts pulling away from the edges and we lift it tonight to find the concrete floor is wet underneath...not soaked...but wet..

Now...there is no other water problem in the house and we have french drains...but this vinyl appeared to have trapped water...

So what to do...I have tile I was going to use (I have had it for years)...to replace the vinyl but I am concerned...

I have tile in a basement bathroom and no problems in the past 7 years...but what to do....

Tell me...

Right now I am using this stuff I bought to remove paint to see if I can bring up the ancient mastic from the original tile that had been there.... perhaps if I can clean the concrete...I can stain it???

[Longhorn]

1. I ran your post past my husband

(a remodeling contracdtor) and he said it sounds like there may be a missing or failing vapor barrier under the basement and vapor is getting caught under the vinyl. He said they make all kinds of concrete sealer that you can put down and then tile. Good luck! :hi:

[Warpy]

2. GMTA

because I was going to suggest sealing that concrete, too. Putting tile down over that unsealed concrete that is wicking moisture up from the dirt below it is a losing proposition. The tile will fail and the problem will be the same as with the linoleum, a reservoir of damp and dark underneath that provides a paradise for all sorts of molds, most of which you don't want to breathe.

[bleedingheart]

4. we are in the process of removing the old adhesives

from the concrete and afterwards we will seal the concrete...

[Kolesar]

3. We have a concrete floor that was poured over dirt and it wicks moisture to the surface constantly

There are small pools on the surface occasionally. In those areas, we have "effluorescence", which is calcium crystals from the concrete that dissolved and wicked to the surface.

The floor has no vapor barrier and no layer of rounded (river bank) gravel to direct the water away to the perimeter drains. I think they call this problem a "rising damp", which means capillary action will draw water all the way up through the soil and the concrete from the water table.

If you attached ceramic tile with mortar, the moisture would probably wick up through the grout around the edges. Very distasteful.

Concrete sealer seems like an option if the concrete is in good shape. (Ours is spalled and pitted.) I cannot really say. I have never evaluated the sealer. Good luck

[bleedingheart]

5. ours isn't that bad...

the concrete is in great shape...I just don't think it was sealed properly...or ever for that matter.