Originally Posted by Steve Snider

I am a marine surveyor and the moisture meter is one of my tools that I use on every boat. The moisture meter does indicate moisture although it can also indicate a high reading due to a void in the laminate or wood in the transom. Sounding the area with a phenolic hammer will help determine if moisture is present. The ONLY real proof of high moisture is to use destructive testing to get a core sample or drill a small hole to see if water runs out. It should also be noted that bottom paint and some resins also will set off a moisture meter to read high moisture when there really is no moisture in the laminate. The moisture meter is a tool that is valuable to use around thru-hulls to determine if the thru-hull is bedded properly. The moisture meter is a tool that indicates possible moisture. Follow up testing should be used to prove the mosture meter reading.