In the market for moisture meters? If so you’ll have a ton to choose from. Peruse the internet and you’ll be overwhelmed by all the brands and types that are available.

If you’re already sold on a certain brand, then all you’ve got to figure out is what type of moisture meter you want/need. For use with solid materials like wood and drywall (concrete is another matter/meter) then basically it comes down to two types: pin and pinless. So, what’s the difference?

Moisture Meters

Pin type (invasive) meters with permanent or detachable pin probes show diverse moisture levels at different places. The reading of % of moisture content is determined by measuring the electrical resistance between the tips of the two pins. What they don’t show is the difference in moisture levels between the surface and ½” down. To get correct readings from deeper areas, long insulated pins are used that only have the uncoated tips exposed, providing an accurate reading of moisture content at various levels of penetration.

Pinless (noninvasive) moisture meters use electro-magnetic sensing technology to measure up to ¾” beneath the surface. They operate by pressing measuring pads on the back of the meter against the surface to formulate a measurement. Meter manufacturers recommend a hand pressure of no more than 3 pounds to insure there’s good contact between the material and the meter. Also, each meter brand has a preferred way to hold it. So, refer to the manual to see the best way to use yours.

The Pros and Cons

• Pin meters are excellent (and necessary) for in-depth evaluations of moisture content. Their downside is that they leave holes that need to be repaired.
• Pin-less meters are limited as to the depth of their readings but can take measurements of large areas very quickly without leaving behind any damage. They’re also useful for detecting problem moisture buildup that may be invisible to the human eye.
• Pin-less meters need a flat, smooth surface to work properly. Rough or porous surfaces can distort the readings given by the meter and can even damage it.

Since you’re likely to need both pin and pinless meters, you may want to invest in a pin/pin-less/all-in-one moisture meter that’ll help you determine what lies beneath. That way you can use just one tool to identify problem areas and then pinpoint the exact location where moisture damage or buildup is occurring.