Quick note as I'm on a remote phone connection.
I have had OSB floor give high readings due to a fungus growing on the bottom side if the OSB next to wet insulation. The wood is hard, but I can see the white chalking if something growing on it. It shows up in my 2004 T1950 post towards the end.
Mark some spots on the floor that have the high readings. Record the readings and recheck every few days. Then let air get to the bottom sides of the floor so it can dry out. As the days go by with air getting to it, the moisture keeps dropping. It took 2 weeks to go from 75% down to ~ 10% of good dry temps. See is this helps any
Yes, metal will trick the meter if you are over the top of it. But there is no metal in OSB other then screws etc that I know of. Make sure the camper frame is not under the location you are scanning.
Hope this helps and let us know how you make out.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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