How to Prevent Costly Moisture Damage to Wooden Pallets

In a world of easy travel and transportation, we have access to products of every kind via shipping.

But the shipping process doesn’t come without its challenges, and one of them is moisture.

Moisture not only affects the pallets themselves. It can also damage the products placed on them. And that can impact your bottom line.

Even if the products were in tip-top shape when they were prepped for shipping, that won’t matter to your customers. If damaged goods are what they end up receiving, then you’re likely to receive their frustration and their demand for refunds.

So, if you’re a company that uses wooden pallets when you ship your products, here’s how to prevent these issues, especially with moisture content measurement.

You’ll learn:

• How moisture affects wooden pallets
• Why you should test their moisture content
• How to prevent moisture issues

How Moisture Affects Wooden Pallets and Products

Excess moisture in wooden pallets can become a home for mold and lead to the decay of the wood. These issues can result in problems with the strength and integrity of the pallets and affect the products themselves.

Marshall S. White, director of a pallet and container research lab at Virginia Polytechnic Institute and State University, wrote out a whole list of effects moisture can have on pallets.¹ It…

• reduces pallet strength and stiffness
• adds useless weight
• corrodes metal products
• causes odor, which contaminates products
• causes staining of products
• leads to wood shrinkage
• causes splitting and warping of pallet parts
• loosens joints
• causes mold and mildew growth

But those are not all.

Another issue is cargo sweating or container condensation.

When the walls and roof of a shipping container cool below the dew point of the air inside, water droplets form on the inside of the container. This is called container condensation, or container sweat.² It’s like your car windows fogging up when it’s cold outside and warm inside.

The condensation then causes little water droplets to run down the sides of the container, possibly damaging the pallets and the products in them.

How does this relate to pallets with extra moisture?

See, three factors are necessary for condensation to happen: (1) a source of water vapor, (2) a difference in temperature, and (3) a pathway for the water vapor to move to a cold surface.³

Wet pallets, unfortunately, are a source of moisture that can make cargo condensation possible.⁴

That’s one major reason for shipping companies to measure the moisture content of their pallets.

Why You Should Test the Moisture Content of Pallets

Moisture testing protects your products from moisture damage in shipping. It allows you to know the true moisture content of your pallets and get them to a safe level that won’t cause damage. This way, you’ll maintain product quality while saving the costs of damaged goods.

You may think, Well, why waste the time? If damage does occur, insurance will cover it.

But that’s not necessarily true.

Damage from condensation or cargo sweat is usually not an “insured peril,” so even an all-risks cargo policy may not cover it.⁵

And you’ll be left to foot the bill to replace the damaged item.

For this reason, the Timber Packaging and Pallet Confederation (TIMCON) best practice guide sets a target surface moisture content of 19%, plus or minus 3%, for dry pallets. The upper limit, 22%, is the risk threshold for mold growth.⁶

If the wooden pallets will carry metal products that could corrode, Virginia Tech’s pallet research program recommends drying them to less than 20% moisture content.⁷

So let’s take a look at the best way to check that pallets have reached these levels.

How to Prevent Moisture Issues with Wooden Pallets and Shipping Cargo

Testing wooden pallets with a moisture meter before shipping is a key step in preventing moisture damage during shipping. The goal is to make sure the pallets are at 22% moisture content or less (also check for any regulations your company needs to follow).

The best way to do this is with a pinless moisture meter that lets you scan a pallet and get moisture content results in seconds. You’ll be able to test large quantities of pallets without adding several more steps to your packing process.

Test throughout the boards of the pallet, rather than just at the ends.

Then, you can be sure you’re getting a representative picture of the moisture content.

If you can, check the pallets before purchasing them to avoid acquiring any wet ones.

Then, measure the moisture again before loading them with products. This gives you an opportunity to remove a pallet that could otherwise cause problems in the shipping container.

Also, be conscious about where you’re storing the pallets.

Keeping them outside is probably not the best idea unless you’re in a very dry climate.

Wood tends to absorb moisture from its environment. According to one source, “a standard EUR-pallet can absorb up to 20 litres of water, and a standard 40 feet container accommodates about 40 pallets. Doing the maths, you will realise there can be a huge amount of water inside the container – 800 litres of water is almost like having two full bath tubs with water!”⁸

Storing pallets in a dry environment and testing them before use helps keep that much moisture out of your shipping container.

Protect Your Products and Profits

Excess moisture in wooden pallets is not just a matter of damaging the pallets themselves. It’s a risk to the products within.

So, when you take precautions like testing moisture content and storing pallets in a dry area, you’re extending the life of the pallets as well as protecting the products.

That means protecting your investment and the profits you’ll receive from those products.

Take a look at our pinless moisture meters to find one that suits your business.

Shop Industrial Wood Moisture Meters Shop Orion Moisture Meters

1. White, Marshall, “Water in Wood Pallets: The Facts Behind the Opportunity Available in Dry Pallets,” Industrial Reporting, Inc., 1997.
2. “The Effect of Water Moisture Damage on Containerised Cargo,” International Institute of Marine Surveying, Dec. 9, 2015.
3. Ibid.
4. Ibid.
5. Ibid.
6. Dry Pallet: Process Standard for Timber Pallets, Best Practice Guide, TIMCON.
7. “Frequently Asked Questions,” Center for Unit Load Design, Virginia Tech.
8. “Container Rain: What It Is and How to Prevent Moisture Damage,” Greencarrier, Oct. 28, 2015.

Last updated on October 14th, 2026