Pinless moisture meters only give accurate percentage moisture contents, when the readings are corrected for different wood species or for the material being measured. In addition, the measuring depth is important. Most meters are calibrated for a fixed measuring depth of ¾” deep. Dual-depth scan moisture meters are available with 2 independent sets of calibrations, one for ¼” deep and one for ¾” deep.
It should be noted that measurements generated by pinless moisture meters are an average of the entire measuring field. This works well if measuring a solid piece of wood or other uniform material at least as thick as the measuring depth.
For standard moisture meters with ¾” calibration, the floor plank should be solid and at least ¾” thick for accurate measurements in percent. However, the indicated value is only a true percent value, if the meter has been set to correct for the wood species.
These requirements are not fulfilled when measuring floor planks 5/8” thick, or when measuring floor planks composed of different materials, such as wear layer, core material and backing.
Measuring floor planks thinner than ¾”: If the floor is installed over a concrete slab, there is always a possibility that the concrete underneath the floor is included in the measurements. The indicated moisture value is then higher than the actual moisture content of the floor. If you use one of the dual-depth meters with the ¼” depth setting, you can be sure that the concrete of the subfloor underneath the floor planks is not included in the indicated moisture value.
Measuring engineered floors composed of different materials: It can be hard to find the correct setting even if the floor is ¾” thick. Using a dual-depth moisture meter on the ¼” setting, you get a valid moisture value, corrected for the wood species used in the wear (top) layer. If you have access to a well acclimate piece, then from those values, you can find a setting for the entire floor plank.
Lignomat pinless meters are ideal for measuring boards, panels and floor planks as well as scanning for moisture problems in floors, walls and ceilings. Large areas can be scanned quickly, and no effort is needed to insert pins into hard wood. No pin holes are left, which is crucial when measuring finished products and wood floors. If measuring low moisture contents is part of the scope of the moisture meter, Lignomat’s pinless moisture meters measure lower moisture contents in hardwood than pin moisture meters. There are also limitations of pinless meters that a flat surface is needed. Pinless moisture meters work on rough sawn or scrapped wood, however round and oddly shaped pieces cannot be measured accurately.