i am preparing to have 3/8" solid hardwood glued to a concrete slab. I decided at the beginning of the project to remove the tile at the foyer so the wood would be consistent across 2 adjacent rooms. The tile covered approx 50sq ft. yea, it was a job removing it but the problem is (or is it) that the moisture reading where the tile was removed showed about 2% on the meter. all other areas was less than 1%. While experimenting with testing in a few locations, I noticed that if you pressed down a bit on the meter, the reading went to 5% or more at the previously tiled area.

2 questions:
1. why is the mositure content higher under the tile than other areas and will it be a problem?

2. when using the moisture meter, what is the proper use? should you apply a bit of pressure on the meter to make good contact with the concrete surface or just let it lie?

I have saved a couple of clients the mistake of having wood in front entryways that had moisture issues. Driving rains pounding on doors and thresholds, can and do often leak. My Tramex Concrete Moisture Encounter, has found many exterior doors that were fixing to cause a failure, had wood been installed in that location.