Does Surface Moisture Skew a Delmhorst Meter Reading?
Moisture caused by exposure to rain, fog or high relative humidity is easily and accurately detected with insulated pins. If you’re using non-insulated pins, push them 1/16″ into the wood and read the meter. Then push them to their full penetration. The meter reading should increase by 1 to 2 points, just because of the greater contact. If there is no increase, or the increase is less than 1 percent, the wood is wet on the surface and the readings are unreliable. As described in the answer to the question above, readings taken with a surface meter are affected by surface moisture, making it difficult to determine if the surface moisture is a result of standing water caused by rain, or if it is representative of the moisture content throughout the board.