Controlling Wood Moisture Content: A Key Factor in Woodworking Success

Getting wood to the right moisture content is an important part of woodworking that often gets overlooked.

Controlling the moisture content of wood helps prevent defects like joint failures, warped panels, and cracked finishes, which can hurt your reputation and cost you money. This article explains how to correct wood that’s too dry or too wet, how to store it, and how a wood moisture meter helps.

• Why It’s Important to Measure and Control the Moisture Content of Wood
• Keeping Wood At Its Desired Moisture Content
• When Wood Is Too Dry
• When Wood Is Too Wet
• Storing Wood
• How to Store Unseasoned Lumber
• How to Store Seasoned Lumber
• Why You Should Use a Wood Moisture Meter
• Advantages of a Pinless Wood Moisture Meter

If you’re a woodworker, you’ve probably invested in saws, planers, sanders, and various measuring tools. A quality wood moisture meter belongs on that list too. Here’s why.

Why It’s Important to Measure and Control the Moisture Content of Wood

If you build and sell high-quality wood projects, you don’t want a customer to end up with furniture or cabinetry that develops joint failures or gaps, warped panels, uneven tabletops, or cracked finishes.

It would hurt your reputation and your pocketbook, and it can happen if you don’t measure and control the moisture content of the wood. Wood scientist R. Bruce Hoadley, author of Understanding Wood, has been quoted in Fine Woodworking as saying that 90% of woodworking problems involve moisture.

That’s because wood is hygroscopic: it constantly exchanges moisture with the air around it. If the wood is drier than the surrounding conditions call for, it absorbs moisture from the air. If it’s wetter, it releases moisture into the air until it’s in balance.

When the wood is no longer releasing or absorbing moisture, it has reached its equilibrium moisture content (EMC). To put it another way, wood is always trying to reach its EMC.

Before starting any wood project such as building a cabinet or laying down wood flooring (including wood subfloors) the wood must be allowed to reach its EMC. Here’s why.

Wood changes size as its moisture content goes up and down. When wood’s moisture content increases, it expands. When its moisture content decreases, it shrinks.

If the wood hasn’t reached its EMC prior to being used in a project, it will continue to either expand or shrink after the project is complete. If this happens, moisture-related deformities could result.

So, prior to being used in any project, wood needs to reach its EMC in the environment where the wood project will be finally used. For example, if you build a project in a dry shop and it ends up somewhere humid, the wood will swell as it absorbs moisture from its new environment.

Depending on the project, that can cause glue joint failures, drawers and doors that don’t fit properly, and even warped pieces and cracked finishes.

Keeping Wood At Its Desired Moisture Content

Once the wood you’re planning on using in projects has reached its EMC, it should be monitored to make sure it doesn’t continue to gain or lose moisture. This is important because it takes time to restore wood to the correct moisture level and creating projects from wood that isn’t at the correct moisture content is a waste of time and money.

As noted above, it could even hurt your reputation. Proper handling and storage help prevent this. But what if the wood’s moisture content is already off and needs to be corrected?

When Wood Is Too Dry

Wood (including components, parts, and finished products) that’s too dry, such as under 5% moisture content, is difficult to restore to its previous quality. The best solution is to place it in a room where the temperature and relative humidity produce an EMC about 1 to 2 percentage points above the MC you want.

Use several fans to keep air moving across the surface of the wood, then wait as long as it takes for the moisture content to adjust. That might take several weeks or longer.

When Wood Is Too Wet

Wood components or parts that are too wet can often be re-dried successfully. (It’s difficult to successfully re-dry a finished project if the high moisture content is a result of poor storage conditions.)

Place the wood in a warm room where the conditions produce an EMC 1 to 2 percentage points below the MC you want. A little heat speeds up drying. The wood will need to remain in this room until the core has reached the desired moisture content.

Storing Wood

Wood’s hygroscopic properties mean that it should be stored in conditions very similar to those where it will be finally used. Failure to do this could result in moisture-related deformities.

For more on this, read our primer on acceptable moisture levels in wood.

How to Store Unseasoned Lumber

Kiln drying

Wood that has been freshly sawn has a lot of moisture in it. If you leave it in a warm, dry environment the moisture will, over time, evaporate. However, a wood-drying kiln is usually used to speed up the process. Most of the wood you see for sale has been kiln-dried.

Indoor air drying without a kiln

If you have a warm, dry space, you can season wood without a kiln.

Stack the unseasoned wood horizontally with stickers between the layers. Stickers are thin strips of dry wood, typically about 3/4 inch thick, spaced evenly (every 12 to 18 inches) so air can circulate around the boards. Line the stickers up vertically so the boards don’t end up wavy. Green wood bends easily if it isn’t supported evenly.

Is it possible to air dry lumber outdoors?

Yes, outdoor air drying is a common first step for green lumber. But in most areas, the humidity keeps air-dried lumber from reaching the low moisture content needed for indoor projects, so you’ll need to finish drying it indoors or in a kiln.

How to Store Seasoned Lumber

Wood that’s already at the desired moisture content should be stored where it will be used, or somewhere with similar conditions. You’ll need to control the humidity there so the wood stays at the right moisture content.

If you have enough space, store seasoned wood horizontally. That’s the best option for long-term storage and for very thin pieces (less than ½ inch). If you’re short on space, seasoned wood can also be stored vertically indoors.

Storing dry (seasoned) lumber horizontally indoors

If you’re going to store seasoned wood indoors horizontally, make sure it’s well supported. Placing support boards every 16-18 inches will keep the wood from bowing.

You don’t need to use stickers when you store seasoned wood indoors because the wood is already dry and does not need air circulation.

Storing dry (seasoned) lumber vertically indoors

If you don’t have room to store seasoned lumber horizontally, you can store it vertically. Just make sure the rack is raised slightly off the floor so air can flow underneath. The floor might not be as dry as it looks.

Also, make sure the vertically stored lumber is supported at both the top and the bottom to prevent bowing. Finally, small pieces of wood can be stored in a lumber cart. You’ll be able to find instructions online for how to make one.

Why You Should Use a Wood Moisture Meter

Even if you buy your kiln-dried wood from reputable suppliers, there’s still no guarantee that the wood was at the correct moisture content when it left the mill. Even if it was, it might have been stored in an environment that caused the wood’s moisture content to change. If that happened, you wouldn’t know unless you tested the wood yourself with an accurate moisture meter.

A good, reliable moisture meter is like insurance. It helps you protect your projects, your reputation, and your investment in wood.

That’s why major wood products manufacturers use handheld moisture meters, and often in-line moisture measurement systems on their production lines, every day.

A quality moisture meter is a critical tool for anyone who works with wood.

Advantages of a Pinless Wood Moisture Meter

Many professional woodworkers prefer pinless wood moisture meters for the following reasons:

• They don’t leave holes in the wood as pin meters do.
• They allow you to scan many board feet in just seconds. Compare this to the time-consuming process of taking multiple moisture readings with a pin meter.
• They usually don’t require corrections for wood temperatures above or below 70°F, as pin meters do.
• Moisture readings aren’t affected by the orientation of the grain.
• They’re easy to use. Just turn the device on and start scanning.

Wagner Meters makes a range of pinless digital wood moisture meters that fit easily on a hobbyist’s tool belt. Every model in the Orion^® line comes with a 7-year warranty, and Orion meters can be used on common softwoods and hardwoods as well as denser tropical species.

Build your wood projects the way the pros do, and avoid common moisture-related problems.

Shop Orion Moisture Meters

Last updated on October 9th, 2026