I recently laid a commercial vinyl tile over the cement slab in my 14year old Minnesota basement. I used Armstrong tiles with the armstrong mastic. The cement appeared dry and the temp was 65 to 70. Now, a few weeks later, I have noticed that in a couple areas (about 4 sq. ft.) the glue has oozed out the seams and if I press on the seams there is moisture present. The tiles seem tight. I do recall noticing over the years that those two areas of the cement slab were dark with moisture when the humidity was high but they looked as dry as the rest of the basement when the humidity in the air was low. How big a problem is this and what can I do now to fix it?
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Replies
VFG: There is a good chance that a vapor barrier was not installed or it has failed. The mastic may have been a water base adhesive which will not cure with water or moisture trapped under the floor tile. Good Luck.