How to Choose High-Quality Wood Using a Moisture Meter

Every woodworker wants to avoid the sinking feeling of a project ruined by wood moisture issues. We’re talking about warping, cracking, adhesive failures, and so on. And if it hasn’t happened to you, it’s only a matter of time—unless you take the proper precautions when selecting your wood.

But here’s the good news—moisture-related disasters are preventable. And it starts at the very beginning.

It’s as easy as using a high-quality wood moisture meter to select wood for your next project. With a moisture meter in hand, you can detect how much water is hiding inside your wood, so you won’t end up with wood that’s too wet or too dry.

So let’s talk about:

• Why moisture content matters when selecting wood
• How to select high-quality wood using a moisture meter
• And what type of meter works best for you

No matter what project you’re choosing your wood for, you’re on the right track to protecting your work and your reputation.

Why moisture content matters when choosing woodworking materials

Whether you’re a hobbyist or pro, it pays to understand how moisture can impact your project. Wood needs to reach equilibrium moisture content (EMC)—so it will stay within an acceptable moisture content (MC) range—before you start your project. Using wood that’s too wet or too dry can cause issues like cracked tabletops, adhesive failures, or warped wood floors.

But here’s what’s worse. These issues might not be obvious until your woodworking project or hardwood floor is in your customer’s home. Not what you want for your reputation.

Dr. Gene Wengert, a Professor at the University of Wisconsin-Madison, says,

“At least 75% of the wood manufacturing problems I review in the University’s Forestry Department are moisture related.”¹

Wood is hygroscopic. That means it absorbs or releases moisture in response to the surrounding air. If the wood is drier than the air, it’ll absorb moisture and swell. If the wood is wetter than the air, it’ll release moisture and shrink.

Wood will continue this process until it reaches EMC. That’s when the moisture content of wood matches the moisture content of the environment.

But the process can start all over again, like when you take wood into a new environment. Even old, kiln-dried, or coated wood will try to reach EMC. It’s a natural, unstoppable process.

Small fluctuations during the year are normal. That’s why drawers might stick during hot, humid summers.

But bigger fluctuations in moisture content can cause damage. And it’s hard to reverse once a project is complete.

Fresh-cut wood usually contains 40-200% moisture content. Yet it’s only acceptable to work with once it’s within about 2% of a specific MC range. These are the general guidelines:

• Wood objects for indoor use (like furniture): 6-8%
• Wood flooring: 6-9%
• Construction (like framing): 19% or under
• Outdoor projects and firewood: 19% or under

You can’t tell if wood is wet or dry simply by touching the surface. The wood at the core is often wetter because wood dries from the outside in.

So how do you know if wood has reached the moisture content you need before you leave the hardware store, lumberyard, or delivery truck? By using a wood moisture meter to go beyond the surface and get a true picture of the woods moisture content.

And that’s what we’ll talk about next!

How wood moisture meters work for choosing high-quality wood

It’s smart to take moisture meter readings on wood before you purchase it for your project. And with a handheld, pinless moisture meter, it’s quick and easy to do at the sawmill or store. That way you only take home wood that’s right for your project. Not too wet. Not too dry.

So what kind of moisture meter do you need?

There are multiple types of moisture meters used to measure moisture levels in various building materials, such as concrete, drywall, or even soil. But if you’re a woodworker, you need a wood moisture meter specifically designed to check moisture levels in wood.

A quality moisture meter gives you control at every stage of a project—when you purchase your wood, work in your workshop, or even when you’re working on a wood floor installation in your client’s home.

Now, for a quick overview of the two main types of wood moisture meters:

• Pin-type moisture meters involve sticking two insulated pins into the wood. They measure the electrical resistance of moisture between the two pins.

• Pinless moisture meters send electromagnetic waves into the wood from a sensor pad. They take readings without damaging the wood. They’re also faster to use and measure a much larger area.

Here’s how to use a moisture meter properly.

Let’s say you walk into the store with a non-damaging pinless wood moisture meter. You see a piece of wood you want, and you wonder how dry it really is.

What now?

It’s super easy—and fast. All you do is:

• Find a clean and dry wood surface
• Turn on your meter
• Input the wood species
• Make sure there’s only air behind your wood
• Take your reading on a smooth, flat surface
• Examine the moisture content reading

Pretty straightforward. But we’ll break it down in more detail—and leave you with a bonus tip.

1. Find a clean and dry wood surface

Your wood sample should be at least 2 inches wide by 2.5 inches long to allow enough surface area for measurement.

Make sure the area of wood you’re measuring is free of water droplets and debris. Surface moisture can lead to inaccurate readings. And debris can make it difficult to get the meter sensor flush with the wood (which we’ll talk about in a minute).

2. Turn on your meter

This might seem like an obvious step. Most meters have an on/off button. But, when in doubt, you can check the instruction manual to make sure. And you will definitely want to bring the instruction manual with you to help with the next step.

3. Input the species of wood

Quality wood moisture meters (both pin and pinless) come with the option for species corrections. It adjusts the meter to the specific wood type for a more accurate moisture content measurement. The more tree species programmed into the meter, the better.

This is important because different types of wood have different densities and chemical compositions. Density affects pinless meters, and chemical composition affects pin-type meters. If you don’t adjust a meter for the specific wood species you’re measuring, it can skew the MC readings for both types of moisture meters.

Most meter manuals include a list of wood species with corresponding setting numbers. If you know which type of wood you want, you can check the meter manual before you shop. If you want more species at your fingertips, bring the manual with you.

You’ll press the species button and plug in the setting number from the manual.

4. Make sure there’s only air behind your piece of wood

Before you take a meter reading, make sure your piece of wood isn’t lying on metal or another piece of wood. Otherwise, it’ll skew your results.

Pin-type meters generally read as deep as the pins penetrate into the wood. And pinless meters typically measure around ¼ to ¾ inches deep. So if other material is touching the area near where you’re scanning with a pinless meter, your meter might try to read it as well.

Here’s a simple solution—hold up the part of wood you’re measuring to make sure there’s only air behind it.

5. Take your moisture readings on a smooth, flat surface

Pinless moisture meters have sensor pads on the back. You want every part of that pad in contact with your piece of wood for accurate measurements.

If the wood you need is rough (like for framing), this is where a pin-type meter comes in handy. But keep in mind that every reading you take with a pin moisture meter will damage the wood. And to measure deeper, you’ll need to change out the pins for bigger (and more damaging) pins.

For a pinless meter, press it firmly against the wood’s surface. In seconds, you’ll get a reading of the moisture content in the area beneath the sensor.

6. Examine the moisture content reading

When you take a reading, the moisture measurement will be displayed on the screen. Take note. Then do a few more readings in different spots on the same piece of wood.

If you’re getting a stack of lumber, it’s smart to test several pieces of wood within the same batch. The National Wood Flooring Association (NWFA) recommends checking 40 boards for every 1,000 square feet of wood flooring.

There’s no hard and fast rule for when to say “no” to wood at the store or delivery truck. But getting wood that’s too wet or dry will take more time to stack, dry, and acclimate. So getting it right saves you time.

Here’s an example to keep in mind:

Let’s say you’re using the wood to build an indoor object, like a table. Since the acceptable MC for that use is 6-8%, you’ll want to get wood near 7% MC. If you measure a piece of wood at 13% or higher, it’s best to walk away. You’ll wait forever for it to dry and risk it warping while it acclimates to the necessary moisture level.

Keep searching until you find wood closer to your ideal range.

Bonus tip: Monitor moisture content post-purchase

Let’s say you find wood with acceptable moisture levels (between 6-14% MC, depending on your project). So you take it to your workshop, home, or store.

Protecting your project doesn’t end there.

If the wood you buy isn’t at the ideal MC yet, it needs to acclimate before you use it. A moisture meter can let you know if it’s moving in the right direction.

If the MC of the wood is right where you want it, a moisture meter can help you confirm that it’s maintaining EMC. And if you see the MC begin to creep up or down, you make adjustments to the temperature and relative humidity in the air around it.

It’s difficult to fix moisture issues once a project is complete. That’s why moisture meters are a crucial step in preventing problems. They set you up for success right from the start.

Take it from Phill Ross, owner of Ross Custom Wood Furniture in Oregon. He used a high-quality moisture meter to catch high moisture content in a walnut coffee table before he sold it.

He says,

“If I didn’t have that new meter, I would’ve been shipping out product that wasn’t properly dried. And I probably would have been out of business.”

So how do you choose the right meter for you? We’ll walk you through a few things that can help you decide.

The best moisture meter for in-store moisture testing

As we learned earlier, some nerdy science goes into understanding moisture content. That’s why it’s handy to have a high-quality meter to crunch the numbers. But not all moisture meters are created equal.

We’ll do a quick run-down of the most important features to consider in a wood moisture meter:

1. Accuracy and reliability: You want both in a meter, or there’s no point in buying one.

 

2. Durable build: You work in rugged environments—from your workshop to the job site (not to mention your faithful truck). You need a meter that can survive in them.

 

3. Pin vs. pinless: We recommend taking a pinless wood moisture meter with you on your next wood run. They’re non-damaging, fast, and cover a larger area.

 

4. Effective measurement range: High-quality moisture meters can measure from around 6% to 30% MC (with the lower range being most crucial).

 

5. Species correction: To avoid skewed readings, both pin and pinless meters need to be calibrated for a variety of wood species.

 

6. Dual depth option: Toggling between depths gives you a more complete picture of the moisture inside a piece of wood. It’s also helpful if you work with a mix of wood depths.

 

7. Warranty and customer support: You want a meter with at least a year-long warranty—preferably even longer. And check reviews that mention customer support. You want a company you can count on to walk you through unique moisture situations. Not someone who disappears after a sale.

 

8. Price: Low-quality meters typically cost under $100. High-quality meters range between $100 and $500. A quality meter might feel like a big investment at first. But it won’t feel that way when it helps you cut down on wood waste and customer returns.

 

9. Bonus features: A few other helpful options include calibration verification (avoid the built-in kind), Bluetooth®, and temperature and relative humidity mode.

Set your project up for success

Using a wood moisture meter is crucial when selecting wood, whether it’s one piece or a truckload. It helps you prevent wood damage right from the start—which saves you time and money. And it protects your reputation. (That’s priceless.)

The right meter will be accurate, reliable, and have features that fit your needs. It’ll be quick and easy to use at the store, lumberyard, or during a lumber delivery. And it’ll help you keep an eye on your wood’s MC—even after you buy it.

Start your next project with peace of mind.

1. Wengert, Eugene Dr., “Eliminating Wood Problems—An Industry Review: 10 Ways of Eliminating Wood Problems,” Woodweb, March 18, 2000. (↑)