Pin vs. Pinless Moisture Meter: Choosing the Best Tool for the Job

You’ve heard the debates about whether it’s best to use a pin moisture meter or a pinless moisture meter. The truth is, there are pros and cons to each. And some function better on certain tasks than others. For example, in a finished product like wood flooring, a pinless wood moisture meter fits best. But a pin moisture meter works better on rough and uneven material, or curved surfaces.

But whatever type of project you work on, moisture damage is the enemy. It hits your bottom line. That’s why moisture testing is a must, whether in woodworking, inspection, wood flooring, construction, etc.

Think of the right moisture testing tool as a solid insurance policy.

But how do you decide which tool is right for the job you are doing? Are they both accurate in measuring the same building materials? Are they both easy to use? And how do they both really work?

Let’s go over:

• Key differences between pin and pinless meters
• How to choose the right meter for you
• Pros and cons of pin and pinless meters
• Best type of meters for the job

Let’s start by breaking down exactly how these meters work.

Key differences between pin moisture meters and pinless moisture meters

Both types of moisture meters measure moisture content (MC) inside porous building materials. But as you can tell from the names, they work in different ways. Pin meters measure the moisture between two small pins that you press into a piece of wood. Pinless moisture meters measure MC beneath a sensor plate that you press flat against the wood. And this key difference determines when you would choose one versus the other.

It’s also important to consider the best meter for your material. You’ll find meters calibrated to wood, drywall, concrete, and more.

But for now we’re focusing on how they take moisture measurements: with two pins or a single scanning plate.

Let’s break that down a little further.

Pin moisture meters:

Pin-style or pin-type moisture meters can also be referred to as resistance meters. They take moisture readings between two metal pins (or electrodes). You push or pound the pins right into the material you want to measure. They measure the electrical resistance between the two pins. Less resistance equals more moisture.

Keep in mind that every moisture measurement you take will leave two pinholes behind. But depending on the types of projects you do, that might not matter much.

Pinless Moisture Meters:

Pinless meters are also called non-invasive meters because they measure moisture levels in the area below a scanning plate.

They take moisture measurements by sending electromagnetic waves (radio frequency) into the material. The more moisture there is, the easier the electrical current will move through that material. And this will lead to a higher moisture content reading.

How to Choose the Right Moisture Meter For You

In most cases, there won’t be a single “best moisture meter” for everyone. Both pin and pinless meters have their pros and cons, and they’re better for some projects and materials than others. That’s why many professionals, like home inspectors, keep both types on hand.

We’ll go over all that in a minute.

But here are a couple of general guidelines:

1. If you want to move fast through a large amount of smooth and flat materials, pinless meters often work best.
2. If you work on smaller projects with rough, curved, or thin materials, pin meters are usually better.

But you’ll see as we go that there’s a lot of flexibility in that.

No matter which type of meter you get, quality is king. Unless you don’t mind risking moisture damage, avoid cheap moisture meters. They’re often far off the correct MC enough that it’s almost pointless to have one.

So, how can you tell if a moisture meter is high quality?

Price is a part of it. With cheaper meters, you risk getting readings that are off by several percentage points. So it’s smart to go mid-range or higher. Otherwise, inaccuracies can defeat its very purpose.

Mid-range meters work fine for DIY or low- to mid-risk projects. And higher-end meters are best for professional construction and flooring outfits.

Price range varies between pin and pinless meters. And costs are often comparable.

But high-end, professional pinless meters can cost more because of their high-tech electronics. This technology allows pinless meters to sense deep moisture without causing damage.

But quality also includes factors like:

• A durable build
• A warranty of at least a year
• A manufacturer with a solid reputation
• External options for on-site calibration

What else should you consider? Let’s look more closely at the strengths and weaknesses of both meters.

Pros and Cons of Pin vs. Pinless Moisture Meters

Knowing the pros and cons of each meter can help you avoid getting one that doesn’t fit your needs. High-quality pin and pinless wood moisture meters are usually close in accuracy. And professionals who use both types know that quality pin and pinless meters can both read below the surface. But not everything is equal between them.

Let’s start with the pin moisture meter.

Pros of Pin Moisture Meters

• Localized readings—provides precise moisture readings of the area between the pins.
• Good for irregular surfaces—works on rough and debris-covered material.
• Insulate pin option—allows the meter to bypass standing surface moisture and read it at a specific depth.
• Thick coatings—pins can get through thick coatings.

Cons of Pin Moisture Meters

• Time-consuming—it takes effort to push pins into material (and to follow grain direction in wood).
• Damaging—leaves pinholes for every measurement taken.
• Pin replacement—pins often break or don’t go deep enough, especially with dense materials like hardwoods.
• Sensitive to temperature—wood that is too hot or cold can skew readings.
• Sensitive to the chemical properties of trees—requires wood species correction.

Pros of Pinless Moisture Meters

• Fast—the sensor plate makes it easy to map moisture over a large area.
• Easy to use—requires only slight pressure to get readings, not pushing or pounding in pins.
• Non-damaging—takes readings below the surface without causing surface damage.
• Dual-depth option—allows for both shallow and deep readings.
• Can measure many finished products—reads moisture through many types of thin coatings and finished surfaces.

Cons of Pinless Moisture Meters

• Surface requirements—needs a flat surface large enough for full sensor contact.
• Coating limitations—adhesives, metal, and thick coatings can skew readings
• Depth limitations—set to one or two fixed depths.
• Sensitive to specific gravity/wood density—requires calibration for wood species.

Next, let’s talk about choosing pin vs. pinless based on your primary projects.

Pin vs. Pinless: Best Moisture Meter for the Job

The projects you do will help you decide whether to get a pin moisture meter, a pinless moisture meter, or both. Pinless meters work best on large projects. And they’re better with smooth, flat, or dense materials when pin holes do matter.

Pin meters work best on rough and curved materials, or when pin holes don’t matter as much.

Now, we’ll dig deeper into what works best project by project—and why. (Keep in mind that, these are general recommendations.)

Best Moisture Meter for Large Projects

Pinless moisture meters are great for big projects, since you can measure moisture content over a large area more quickly. Pin meters still work, but it will add a lot more time and effort, as well as pinholes.

Scanning plates also allow for near-instant moisture content readings.

Pin meters will naturally take more time and effort to press the pins into the material. Pins can often break in the process and need replacement. And when measuring wood, you have to follow the grain direction for accurate readings.

But If most of your materials have uneven, rough, or curved surfaces, a pin meter may be your best choice. For example, framing lumber or plywood subfloors can sometimes have rough surfaces.

Pins work best in this case because the scanning plate of a pinless meter may not make full contact with uneven material. And this can lead to inaccurate readings. Plus, aesthetics don’t matter as much in framing lumber and subfloors, so pinholes won’t be a problem.

Best Moisture Meter for Woodworking

The best wood moisture meter for woodworking depends on a few key factors. First, whether you’re okay with your finished product having small pinholes in it. Second, whether you’re often working with curved or flat surfaces.

Pinless moisture meters need a smooth, flat, and debris-free surface for accurate moisture readings. And the piece of wood you’re measuring needs to be at least as wide as the sensor plate. For reference, average sensor plates are between 1.25 and 2.0 inches wide, and between 1.5 and 2.5 inches long.

If you often work on projects like turned table legs and decorated elements, a pin meter would work best.

Pin meters are also better if you work with very thin wood (under .25 inches). Pins can read as shallow as you want, depending on how far you press them into the wood. But pinless meters are designed to measure at .25 inches or deeper.

Keep density in mind as well. Dense woods can break pins, so pinless meters work best for hardwoods.

If you’re a luthier, we’re guessing you don’t want pin holes in a finely tuned instrument. But at the same time, pin meters work better for small or thin pieces of wood.

So, what’s the solution?

Both. Many luthiers and woodworkers keep a pin and pinless moisture meter on hand. They might use a pin meter during the rough-wood phase. But they want a pinless meter as they get closer to finishing.

Whichever type (or types) you choose, always go for a high-quality tool if you want accurate readings. (Which is kind of the point.)

Best Moisture Meters for Wood Flooring and Subfloors

Always check moisture levels in subfloors and floor coverings. This goes for DIY folks as well. If flooring products aren’t acclimated, they can warp and fail after installation.

But measuring moisture content in subfloors is crucial, too. Excess moisture travels upward from subfloors, which can cause mold, odors, or damage to floor coverings and adhesives.

Both a pin or a pinless meter work fine on wood subfloors. But pinless meters will make life easier and faster when measuring dense and thick subfloors.

For concrete subfloors, concrete-specific moisture meters can help you locate moisture hotspots.

Best Moisture Meters for Drywall

Most professionals prefer pinless (non-invasive) moisture meters for drywall. This allows both inspectors and anyone in construction to take quick readings of large areas without leaving holes.

However, keep in mind that many pinless meters give moisture readings on a relative scale—good for locating hotspots and leaks. They might not provide true moisture content in drywall. But there are a few professional pin meters out there that will provide the moisture content of drywall.

You can get moisture meters with specific calibration for drywall. But you can also find professional, high-end wood moisture meters that include calibration for building materials like gypsum (the core material in drywall). This cuts down on how many tools you need to invest in.

Whichever tool you use, the important thing is not to skip moisture testing in drywall. Like in other porous building materials, you can end up with moisture problems. And wet drywall can cause a whole host of issues, like mold growth, compromised material, and more.

Best Moisture Meters for Inspections

As a home inspector, you need a little bit of everything—including moisture meters. Many inspectors keep both a pinless and a pin-type moisture meter on hand. They might use the pin meter for textured walls and ceilings, or cracked logs and beams. But they’ll also have a non-invasive meter to get deeper readings in finished surfaces without doing damage.

Moisture meters are also handy tools for detecting leaks. Inspectors often use a pinless meter to scan large areas to find leaks fast. But some will follow up with a pin meter to get MC on uneven surfaces or drywall.

Quick Reference List For Choosing a Meter

Even though we’ve just covered moisture meter recommendations for a few jobs and materials, this gives you a nice summary, including some materials we didn’t mention. (Remember, these are only recommendations):

• Cabinets/floor covering (smooth wood materials): Pinless wood moisture meter (shallow-depth).
• Woodworking on small, uneven, or thin (< .25-inch) surfaces: Pin wood moisture meter.
• Woodworking on flat, smooth, finished surfaces: Pinless is best, but a pin meter can work, depending on the project.
• Framing (smooth wood materials): Pinless is best, but pinless can work since pinholes shouldn’t be an issue.
• Variety of building materials: A pinless moisture meter with relative mode.
• Drywall/gypsum: A drywall-specific moisture meter. Or a pinless wood moisture meter with a relative setting for drywall.
• Concrete slab: A concrete moisture meter is best, though a pinless wood moisture meter can be calibrated for concrete to locate moisture hotspots.
• Plywood/OSB/MDF: A pinless wood moisture meter, unless the material is less than .25 inches thick.
• Stucco: A pin moisture meter due to the textured surface.
• Non-wood flooring (like linoleum or tile): A pinless moisture meter with relative mode.

Finding the moisture meter that fits you best

Now you know that choosing a pin or pinless moisture comes down to finding the right fit for the project. Pinless meters are your best friend if you move fast on big projects (if you work with smooth, flat, or finished building materials). But pin meters are your best choice if you work with rough, curved, or debris-covered materials.

And if you work on a variety of projects, you might need both. It’s the perfect solution to make sure you’re covered every step of the way.

What matters most is that you don’t skip high-quality moisture testing. Moisture damage like warping, cracks, and mold can cost you significant time and money. And those can be the most precious resources.

Your next step is to explore what’s out there.