Be careful with what you believe you see with a moisture meter.
I own a roofing company. Had a single women client call me about a "leak" on the roof we had installed 14 months ago. She had a friend with a meter show her how the ceiling where a long ago removed and patched hanging light was now a "leak". No one had ever noticed in the 12 years she had lived in the home, the builder's repair after someone relocated the hanging light, and installed the ceiling fan in the better position. I check the roof and found nothing wrong, but was unable to get to the attic ceiling as the sheet rock was nailed to the bottom of the deck/roof rafters, with insulation between.
After trying to explain the long ago original repair to no effect, I suggested the moisture be checked anywhere else in the room or the house. Oh wow, every other place her friend checked had the same moisture readings. I said good bye and left.
But moisture meters can save us heart ache and lots of dollars in our RV's. Just understand how it should be used, to get the help and info that is correct.
Dave and Dolly
1998, 36' Foretravel, U295, rare mid door
2001 Jeep Grand Cherokee