Moisture meters are used to measure the percentage of water in a given substance. This information can be used to determine if the material is ready for use, unexpectedly wet or dry, or otherwise in need of further inspection.

Wood and paper products are very sensitive to their moisture content. Physical properties are strongly affected by moisture content and high moisture content for a period of time may progressively degrade a material.

The problems caused by varying degrees of moisture content in wood go beyond simple shrinkage in the dimensions of wood parts.

Problems with distortions in the shape of the wood, such as twisting, warping and cupping, occur because of the difference in the degree of dimensional change in wood cells.

A moisture meter gives a reading of the approximate moisture content of wood. The reading helps in determining whether the wood is suitably dry for its intended purpose.

The moisture content reading can also assist in planning a project design that will accommodate future changes in dimension caused by changes in relative humidity.

Readings on a moisture reader will generally range from 5 to 40 percent. A range of 5 to 12 percent is considered optimal. A reading of up to 17 percent is generally considered moderate moisture and acceptable.

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