In article ,
"The Medway Handyman" writes:

So, what reading is 'normal' & what reading is 'damp'?

A reading of 20Mohms is dry. (Dry isn't necessarily normal.)
Reading also depends how far apart the probes are.
IME, you don't need to worry unless you get something less
than 1Mohm, but usually you'll get 20Mohms if dry.

--
Andrew Gabriel
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