How to Check the Calibration of a Wood Moisture Meter
Have you noticed that your moisture meter has been showing higher or lower readings than you expect? Are you getting clearly inaccurate readings, like a dry piece of wood reading as wet? Or has your meter been dropped or struck by something heavy? Then it might be time to check its calibration.
Wood moisture meters are an important tool for wood flooring projects. Testing the moisture in wood helps you avoid costly flooring failures and maintains the quality of your work, and the type of moisture meter you use makes a difference. When it’s calibrated correctly, you can trust it to provide accurate moisture readings—a necessary ingredient for any successful flooring project.
But what is calibration, exactly? How does it work, when should you check moisture meter calibration, and what’s the recalibration process?
Let’s break it all down:
- What calibration actually is
- How to check pinless meter calibration
- How to check pin meter calibration
- Meter recommendations for your projects
Let’s start with what calibration is and why it’s a must for effective moisture testing.
What is Calibration (and Why Does It Matter?)
Calibration in a moisture meter means that moisture meter readings are tuned so that as many readings on wood are as close as the meter can provide to oven-dry testing results—the #1 benchmarking method for wood moisture measurement.
The acceptable moisture levels of wood and lumber range from 6% to 8% for interior use and 9% to 14% for exterior use.
As moisture content in the wood changes, the wood will either shrink or grow. And that can cause changes in the shape of the wood. And if you’re working with inaccurate moisture readings, this can lead to flooring failures like cupping, warping, shrinking, and even gaps.1 These kinds of failures can be costly to repair in both time and money, so using a properly calibrated meter is essential.
When you buy a moisture meter, it should already be calibrated for you. This means you can start taking moisture readings right out of the box. But we do recommend you double-check the calibration before first use by using a calibration verification reference (CVR) device.
During the life of a moisture meter, certain things can throw off the calibration. This might mean dropping it, having it bounce around in your vehicle repeatedly, or even leaving it outside where it gets rained on. That’s why it’s important to clean the meter and leave it in its case. That not only protects the hardware, but also the software inside.
So if you think your meter’s readings might be off, what kind of calibration test should you use? We’ll discuss that next.
How to Check the Calibration of Your Bessemeter Pinless Moisture Meter
Because moisture can wreak havoc on a flooring project, take care of your meter and check its calibration regularly, especially if you think you might be getting inconsistent or false readings. Please note that other meter brands have similar procedures. If you have a different brand, check their manual to learn how you can do a calibration check.
If you have another meter that’s giving different readings, you can check a piece of wood with both meters (making sure they are both set to the correct wood species) and compare the results. If the percentages differ, this may verify your suspicions that calibration is off on one of the meters, and you can call the manufacturer for next steps.
If you don’t have another calibrated meter that you can use for verification, you’ll need a CVR device, which is usually sold separately.
Once you have your CVR, follow these simple steps to test the calibration of your moisture meter:
1. Place the CVR device on its legs on a non-metallic surface.
2. Turn the moisture meter on, and then use the MATERIAL button in conjunction with the up and down buttons to set the specific gravity to .50.
a. Press ON/OFF to return to the reading mode.
3. Place the meter on the CVR, correctly “seating” the meter’s sensor pad firmly in the recessed area of the CVR.
4. Apply light downward pressure. Record the reading you receive and check it against the moisture content percentage listed on the back of the CVR.
Your CVR should include a note letting you know which moisture meters to use with that particular CVR and the range of moisture content readings that are acceptable. For example, the Bessemeter CVR includes a note on the back that says, “Your Bessemeter should read within +/- 1% MC of 17.0% for ¾ depth and 10.9% for ¼ depth.” These readings are for the D300, S300, and DS500 models only.
When checking the calibration, make sure there’s no surface moisture on the CVR or meter by wiping them both down with a cloth. And when inserting the moisture meter into the recessed area of the CVR, make sure to apply light pressure on the moisture meter to get accurate readings.
If your readings go outside the range listed on the back of the CVR, then the moisture meter will need to be recalibrated.
To do this, it has to be sent back to the manufacturer. The manufacturer will know the standards, specific procedures, and specialized equipment needed to readjust the device.
So while you can’t recalibrate your pinless moisture meter yourself, you can check to see if it needs to be serviced.
How to Check Calibration of a Pin Meter
A pin meter’s calibration check procedure requires a moisture content standard (MCS) to do an external calibration test. An MCS is a small box with contacts or clips that’s been calibrated to a known value.
- Touch the meter’s pins to the contacts or clips.
- Compare the meter reading to the MCS’s known value.2
If it’s within the specified range, your meter is calibrated. If it’s not the meter needs to be serviced.
Choosing a Reliable Moisture Meter
Having accurate, reliable, and consistent wood moisture readings is essential in any flooring project, and your flooring projects deserve one of the best moisture meters on the market.
Bessemeter has a variety of industry-leading options, and all of their moisture meters are ready to use out of the box, already calibrated.
Take care of your moisture meter, check its calibration every once in a while, and keep churning out quality work for your clients. Not only are all Bessemeter moisture meters calibrated from the start, but they also provide services to recalibrate your meter for you if it’s damaged and the calibration has been thrown off.
For consistent and accurate readings in the palm of your hand,
- “How to Avoid Common Mistakes with a Moisture Meter,” Bessemeter. (↑)
- Smith, Ron. “Calibrate Your Wood Moisture Meter—Simple Steps,” Wagner Meters (Dec. 5, 2025). (↑)