10 Features to Look for in a Wood Moisture Meter
“At least 75% of the wood manufacturing problems I review in the University’s Forestry Department are moisture related. That’s why eliminating wood problems begins and ends with monitoring and controlling the moisture content (MC) in wood.”
So says wood expert and professor emeritus in Wood Processing, Department of Forestry, at the University of Wisconsin (Madison), Dr. Gene Wengert.
Everyone who works with wood needs a top-notch tool for monitoring the MC of wood in their inventory, whether you’re a professional woodworker or wood flooring installer, or a weekend carpenter who loves to build with wood. A high-quality moisture meter for wood is the tool that lets you track wood’s MC and confidently determine when it’s reached the MC% for its in-use location. The very best moisture meters are also the easiest to work with and provide added-value features beyond reliably returning accurate moisture measurements.
Here’s our list of the top ten most critical features you want in a top-shelf moisture meter.
Without demonstrated accuracy – what’s the point? Whether you’re installing wood flooring or building cabinets, you need to know the wood’s MC within a percentage point to ensure that there won’t be future moisture-related flooring failures. In some cases, like with firewood, being off a point or two in MC percentage won’t have enormous consequences. However, in most cases, not having accurate and thorough moisture readings of the wood’s MC can have catastrophic consequences. Even if the physical damage isn’t catastrophic, the damage to reputations can be. In this way, using a cheap, inaccurate moisture meter can be the most expensive option.
Cheaper moisture meters have a greater margin of error for specific readings. Meaning, the reading you see on the lower-end meter may be well off the wood’s actual MC. Indeed, cheaper moisture meters can’t even read MC in the low range, which is precisely the MC range where an accurate reading is most critical. Range accuracy is so important, it gets its own spot on our list of most critical moisture meter features.
We’re proud that our brand is synonymous with accuracy, a claim supported by third-party testing. When comparing Wagner meters with other leading brands, including pin meters, third-party tests demonstrate that Wagner moisture meters for wood provide the most accurate readings.
Repeatability is a marker of a meter’s reliability. It answers the question of whether the same meter will take the same reading on the same spot in quick succession. Basically – can you depend on the meter’s internal components to measure moisture accurately every time.
Think about it: Say a reading on spot A is 14%, and when you take a reading at that same spot a minute later, your meter now reads 12%. That doesn’t seem right. Take a few more readings on spot A. Are four of the readings consistent, and there’s one outlier? Not ideal, but it happens.
Are the readings all over the place? Poor repeatability indicates a meter that’s poorly designed, poorly constructed, has inferior components, or most likely – all three. Toss it. You should expect your moisture meter to return the same measurement when used on the same spot within a short period.
Working with a calibrated moisture meter is essential. The meter is nothing more than a hunk of plastic and metal if it’s not calibrated. Worthless. Worse than worthless if you use an uncalibrated moisture meter, because then you’re working with bad information.
The good news is that the top line moisture meters will rarely fall out of calibration. If you drop the meter or if it’s been physically impaired somehow, then the internal components may have been damaged as well – which can result in the meter becoming uncalibrated.
Some meters will promote their “built-in” calibration test. Two things to remember: These built-in check tests are vulnerable to the same damage that may have uncalibrated the meter. They’re just another set of internal electrical components. Second, this feature is just a test; it does not recalibrate the meter.
The only reliable way to test your meter’s calibration is with an external calibration testing tool. Many meter manufacturers also sell calibration testing tools. If your meter is uncalibrated, you’ll have to send it to the manufacturer for recalibration. The only exception to this rule is Wagner’s Orion® line of moisture meters. Every Orion moisture meter comes with an On-Demand Calibrator you can use to recalibrate that meter in under a minute.
4. Moisture Measurement Range
No hand-held meter can accurately read MC above 30%, which is the percentage at which most wood species have maxed out on the amount of bound water they can hold. This limitation doesn’t impact the quality of your end product because when the MC is high, even if already below this 30% marker, your main takeaway is often that the wood needs more time drying. When wood gets into the lower MC ranges is the time that you need to know whether the MC is in a one to two-point range around the goal MC percentage you need for that wood’s intended end-use location.
When you look at how low your moisture meter for wood needs to go, how you use the wood is the determining factor. For example, if you’re building furniture or installing wood flooring, you’ll want to be able to measure MC as low as 5-6%. The in-use location for the wood impacts its MC target range, even if it’s indoor flooring or furniture. Yet even a non-humid state like Arizona won’t need wood dried down to five or six points. Thus, the five to six-point range is a useful bar for low range readings to ensure that your wood hasn’t overdried, which can cause as many problems as wood being too wet.
5. Depth of Reading
Wood dries from the outside in, leaving the core with more moisture than the wood’s surface. Consequently, you need a meter that takes its MC readings at the proper depth within the wood. Most woodworking projects, including flooring, are covered by meters that can measure at either one-quarter or three-quarters of an inch below the surface. The thickness of the wood indicates the depth at which the MC measurements should be taken.
Many non-invasive moisture meters have a dual depth setting. Meaning, you program a depth setting indicating whether you want the moisture sensor to read to a quarter or three-quarters inch depth. Pin-style meters can measure at whatever depth the pins are inserted. Some pin meters let you swap out the pins so the same meter can be used to measure at different depths. For example, deeper readings require a bulky hammer-probe add on to reach the lower depths of the wood. One of the challenges with pins is making sure they reach the proper depth. Insulated pins can measure at the depth at which the pins have been inserted into the wood. But insulated pins come with other challenges, namely ensuring that the insulation hasn’t been compromised.
Pin-style meters with “uninsulated” pins measure the path of least resistance, which could be the wood’s surface. However, if there is no water or condensation on the surface, then the pin meter may instead take a reading at a lower depth, but you may not know how deep.
6. Scope of Species Settings
Each wood species and subspecies have their own distinct chemical and physical properties that impact how moisture meters calculate their MC. Pin style moisture meters are affected by the wood’s chemical properties, while pinless moisture meters are affected by the wood’s density. You cannot get an accurate moisture reading without accounting for the species of the wood being measured.
The more advanced moisture meters come with a species setting that lets you identify what species is being measured. Once you select the right species, the meter will do the necessary calculations to return an accurate moisture level for that species. A standard species range will cover the most commonly used woods. If you work with a wide variety of species, you want to get a meter with a species setting range that covers the ones you need. If that includes exotic species, then select a moisture meter with an extended species range that covers them.
A lower-end moisture meter may not have a species correction feature. Consequently, any user of these meters will have to use an adjustment table to adjust the meter readings into a more accurate moisture measurement for the specific species.
7. Data Collection and Management Capabilities
All moisture meters return a moisture reading. That’s their job. A comprehensive moisture meter goes well beyond that basic function to help you make decisions based on the woods’ MC.
Some moisture meters also read ambient relative humidity and temperature. The Orion 950, Wagner’s top-of-line wood moisture meter, uses this additional data to return more information than just the moisture level. For example, it will calculate the equilibrium moisture content and dew point for you.
Professional woodworkers and flooring installers might also look for a wood moisture meter that provides state-of-the-art data management capabilities. Both the Orion 940 and 950 can store moisture readings on the meter, as well as give an average high-low analysis. If you want to keep historical data for long-term recordkeeping on a project basis, the 950 has Bluetooth® capabilities that let you transfer data from the meter to one of its free moisture data mobile apps.
Was the meter built to last or designed to fail?
It’s an odd question to wonder whether a tool was designed to fail. Yet keep in mind that some meter manufacturers make more money selling pins over time than they do the actual meter. Pins regularly get bent, dulled, or damaged. If you’re using a pin meter, you’ll have to replace the pins regularly. Think of pin meters like razors; the manufacturer can low ball the apparatus because the money is in the replacement blades or pins.
You also want to consider the durability of the meter’s physical casing. A meter contains a lot of electronic parts that are vulnerable to dust and (yes) moisture. A cracked casing compromises the integrity of the meter’s calibration and may prevent it from working at all.
A good indicator of a meter’s durability is the length of the manufacturer’s warranty. Low-end pin meters might come with 60 to 90-day warranties, while the better ones typically come with only a one or 2-year warranty.
Wagner’s products, in contrast, have an industry-leading 7-year warranty, a compelling testament to the company’s complete confidence in the durability and workmanship of its meters.
Free Download – Is a Pin or Pinless Moisture Meter Best For You?
9. Ease of Use
When it comes to assessing wood’s moisture condition, it’s crucial to take multiple meter readings. The large the piece of wood or the larger the batch, the more readings you need to take if you want a complete picture of the moisture condition. If you don’t take enough moisture readings, you may not get an accurate determination of the overall moisture condition.
So, you see where I’m going with this.
It’s human nature to look for a short cut, especially if a task or tool is unwieldy. An easy-to-use moisture meter is a meter that gets used often and used correctly.
Speed is another area where our pinless moisture meters give you a huge advantage. Let’s say you’re taking a sampling of 20 meter readings across multiple boards. How difficult is it to get those readings? How long does it take?
At Wagner Meters, we like to say you can move three times faster with our pinless meter than you could if you used a pin meter to take readings. That’s because our pinless moisture meters can scan large bundles of wood in seconds. You can also configure our wood moisture meters to sound an alarm if a reading exceeds a threshold you set. Using this alarm feature, you don’t even have to stop to check the meter. Just press it down on the spot being sampled. If no alarm, move on to the next spot.
People have stopped by our booth at trade shows to dispute our “3x faster” claim. When we ask them what they disagree with, they tell us they’re able to move 10 or 20 times faster with our non-invasive moisture meter than they could when using a pin meter – and that includes being able to measure a much larger area with their Wagner moisture meter.
Other ease-of-use features to look for is the quality of the LCD display, and how easy it is to toggle between functions on the meter. For example, the Orion meter functions work with one-button control, whether it’s to turn the meter on and off, select the species setting, set the depth, or switch the meter to relative moisture mode.
So why do we get to price last? As consumers, whatever we’re buying, we usually look at pricing first. Well, we put price last because when you’re shopping around for an essential tool like a moisture meter for wood, the smart first step is to specify what features you need in a moisture meter. A professional who’s juggling multiple batches of wood, numerous projects, and a variety of species has a different set of needs than a professional artisan who crafts bespoke furniture pieces from locally sourced timber. And the occasional hobbyist has a different set of requirements altogether.
After you write out your list of needed features and some “nice to have” features, then you’re almost ready to start looking at prices.
Since the point of the moisture meter is to provide a moisture reading, never compromise on accuracy. If you want, you can find a basic pin moisture meter for $20 or $80, you can. But you have to question the quality of their design and construction. The moisture measurements from low-end meters are typically affected by surface moisture, which skews the readings. Low-end meters, both pin and pinless, are also more likely to have their readings compromised by ambient conditions. Design and construction matter.
Professional woodworkers especially need to make sure they’re buying a technically sophisticated moisture meter that’s not vulnerable to external conditions interfering with its readings. These wood moisture meters range between $350 – $550, depending on the scope of added features included, which make them a modest investment compared to the ROI a high-quality moisture meter provides.
In addition, take a look at the total cost of ownership, both of repairs, recalibration fees, and replacement parts. Pin moisture meter owners, for example, may find that the cost of replacement pins rivals the cost of the meter itself over its lifetime.
Learn about the differences between a pin and a pinless moisture meter.
A Closing Thought
It’s a proven fact. Improper MC levels in wood can have an extremely adverse impact on the overall quality and durability of your end-product. All the more reason to have a quality moisture meter on hand.
We believe the right moisture meter for wood will be an excellent investment for you. One that can save you money and prevent many headaches in the long run and ensure the durability and quality of your finished products for years to come.
Eric is excited to fight the moisture problems that cause billions of dollars of waste in the United States and the rest of the world. It also helps that he enjoys spending his free time woodworking, and he knows his projects will be free of moisture issues.
Last updated on July 19th, 2021