Maximum moisture to be able to lay tiles

Hello,
we have integrated a small workshop into the garage. The room is insulated but has no heating. It is slowly drying out on its own. We are constantly ventilating. Of course, it takes forever without heat. This week, Lidl had moisture meters. It gives me values in %, whatever that is supposed to mean. The screed is now between 3% and 6%. Does anyone have an idea what the values are supposed to tell me? From when can I start thinking about tiling?

Should the room maybe be heated up? I was thinking about 1 week at 20°C. Would that be enough? What do you think?

Hello, not over 3% before laying. Heat for about a week. Often it is still a bit damp at the edges. Optimal is 2% and recommended if it is not too cold during tiling and for a few days afterwards. 20 degrees would be ok.

Great, thank you!

I am surprised that you mention limits for moisture without specifying the measurement method.

Enter "cm messung fliesen" on Google.

The first result from Albrecht Services gives all the answers.

wasn't that 1.8% or something?!

it was definitely very, very little and you don't measure from the surface but deeper underneath. so you partially damage the floor. that's why a "flag" is embedded somewhere where there is no underfloor heating.

if you lay the flooring too early, it will buckle and you can throw everything away again.