Moisture meter

[dave7108]

I need a device to measure moisture. I think there is a leak under the stone floor in my toilet downstairs. Most of the meters have probes on to push into a wall or wood.

[rodericb]

A moisture meter with probes isn't going to pick anything up if there's tiles in the way (as it appears you know) - pinless/probeless moisture meters use EMF to measure a capacitance change a half inch or so away which will show the presence of moisture. You'll get a reading and have to take multiple measurements around to track where the moisture is travelling.

Depending on the source of the leak a thermo camera (AKA infra red or FLIR) camera might pick it up. If you're able to set up a temperature differential between where you're looking and the water you'll see it visually on the camera screen.

[E-bmw]

Bought one of these when I had a damp issue on my motorhome to see how far I needed to go to get back to good structure.

https://www.amazon.co.uk/dp/B09BJJX1B8?ref=ppx_yo2...

Several different modes & should do what you want for minimal outlay.