Everything You Need to Know About Moisture Meters and How They Work

If you’re a person who creates things from wood, you probably want them to stay in good shape for a long time. Wood must be treated properly so it keeps its freshness. To do that, you’ll need moisture meters. Wood is a hygroscopic material, so its longevity, physical integrity and aesthetic quality mainly depend on how you understand the wood’s moisture condition when you start working with it. It doesn’t matter if you’re laying down a floor, making furniture or constructing a building, wood moisture levels are essential.
To check the moisture you’ll need an accurate wood moisture meter. Let’s see what the most important things you need to know are.

Many industries require a suitable moisture meter to detect the moisture content in certain materials. If you’re a home and building inspector, you’ll have to rely on moisture meters to find potential problems and damages.
In the woodworking industry, people use a wood moisture meter to make sure that they are making a quality product. Moisture content is expressed in per cent (%MC). Some moisture meters have an analog scale, others read %MC digitally. The accuracy of the %MC readings, and the appropriate substrate scales, vary per meter but can also vary by brand and type.

Most moisture meters are calibrated to wood, which gives quite an accurate reading in wood moisture content. This scale ranges in the 5 to 40% range. When testing the moisture content in non-wood materials (concrete), a relative scale of 0 to 100 is used (0 is dry and 100 is saturated).
Moisture meters have visual LED indicators that show the per cent reading on the scale for dry, moderate and saturated or wet readings. Some meters also have a third scale for readings of gypsum. These scale readings range from 0.2 to 50% moisture content.

When it comes to colour indicators on moisture meters they’ll help you determine if the tested material is dry or if there is a potential problem with moisture. The green colour means dry, yellow is for moderate and red is for high.

When inspecting a building or structure materials you can use three types of moisture meters: pin-type, pinless and pin/pinless/all-in-one. All three types of moisture meters give a specialized purpose.

Pin-type moisture meters comes with two pins on the instrument. The two are used to penetrate the test surface at any preferred depth. The %MC is measured at the depth of the head of the contact pins. Pin-type meters use the principle of electrical resistance to measure the % MC; they measure the conductivity between the pins and usually read up to 12/40cm deep. The tips of the pins are quite sharp, uninsulated and go under the surface for a sub-surface reading. This method is an invasive process. You can also get a reading by touching the pins to the surface for testing.

Pinless or noninvasive moisture meters work on the principle of electrical impedance. Such meter gives a non-destructive measurement of moisture in wood and other materials like concrete and gypsum. This moisture meter may is also known as a nondestructive or a pinless moisture meter. The pinless meter scales are similar to that of pin-type meters, where the wood scale reads %MC at 5 to 30%. When it comes to the reading of nonwood materials like concrete, the scale reads %MC from 0 to 100. Pinless moisture meter reads up to a typical depth 1.9cm or 2.5cm into a subsurface. You can use them for detecting problem moisture buildup where visual indicators can’t show anything.

Pinless moisture meters are mainly used to determine moisture content on a relative scale of 0-100 in concrete subfloors. They can also be used in flooring before laying a wood floor or other flooring surface. You can also use them for identifying potential moisture buildup under vinyl flooring, behind bathroom/shower tiles, or other finished surfaces. Use them to determine if water-borne finishes are completely dry before a second application.
 

This one is the most useful moisture meter; It’s the type of moisture meter that uses both methods for measuring %MC. This type of meter uses the same scales of %MC for wood and nonwood substrates and provides you with the versatility you need for for a full inspection in determining areas where moisture is a problem.

When you buy a moisture meter for inspection of wood (and nonwood) surfaces, make sure it’s factory-calibrated (fun fact, most of them are). However, you should keep your meter in good working condition and to do that you would have to keep it in a clean and dry place. Make sure you change batteries and pins when necessary. Using the meter when the batteries are low, you may make it to go out of calibration.
Make sure both the electrodes and meter are clean; use a biodegradable cleaner to clean only the external parts. The best way to repair or re-calibrate it is to return the meter to the manufacturer or manufacturer service centre for service and re-calibration.

The simple answer is, yes, you can. Several meter readings in the key locations of the structure will indicate if the areas are in any potential danger of infestation. You can use the pin-type meters for pest control applications if you want to identify the exact point of infestation behind walls and ceilings. The meters allow you to detect moisture in places where pests can grow and live without human interaction. Although fungi and mould begin to grow in wood with a moisture content around 20%, there are insects that live comfortable in wood with only 12%MC.

We hope that we offered you enough details when it comes to wood moisture meters. Make sure you buy yours from a trusted manufacturer and use it accordingly. Using this meter will help you create things of wood that will last for a long time.