Why Does Your Pressure-Treated Wood Feel Wet?

Pressure-treated wood is durable lumber for making outdoor designs, decks, and fences. These woods have been treated to resist rot or microbial infestation that can cause decay in a moist environment. Why, then, does the pressure-treated wood feel wet?

Your pressure-treated wood may feel wet because of waterborne chemicals in the wood’s pores introduced during the wood treatment for moisture resistance. So, when dispatched, the wood may feel wet and heavy.

If your pressure-treated treated wood feels wet, the good news is that you can get it dry. This article will show you how and explain the factors that affect the drying of pressure-treated wood and more, so read on!

Why Does Your Pressure-Treated Wood Feel Wet

How Do You Dry Wet Pressure-Treated Wood?

You can effectively dry your pressure-treated wood using the kiln-drying and air-drying methods. The kiln is more expensive but is faster. On the other hand, the air drying method requires more time and depends on weather and location. 

Pressure-treated wood is essential for your outdoor building project. However, wet lumber can affect the durability of your project.  

The Kiln Drying Method

The kiln drying method is fast and effective. It involves the use of a kiln – a thermal chamber that produces enough temperature that can dry, harden or preserve substances such as wood, ceramics, and clay.

You can get good kiln-dried pressure-treated wood in different ways:

  • You can buy kiln-dried pressure-treated wood, which is usually expensive.
  • You can take your pressure-treated wood to a kiln-drying service.
  • You can also get a kiln and dry your pressure wood yourself.

If you’d rather buy a kiln and handle the drying yourself, consider the RapidFire Pro-LP Kiln (available on Amazon.com) This product is versatile and can be useful beyond your wood drying needs. 

You can also use it for ceramics, glass fusing, jewelry making, and others. It uses a digital control panel and has a wide firing chamber, and it can take in an ample amount of wood.

The Air Drying Method

The air-drying method is another effective method to dry your pressure-treated wood. This won’t cost you anything, which gives it an economic advantage over the kiln drying method. However, it’s time-consuming

All you need to do is to expose your wood to direct sunlight for a while. However, in the absence of sunlight, you can also expose them to heat from your fireplace. You can also keep your wood in an enclosed room with sufficient ventilation.

To ensure that your wet pressure-treated wood is set for use, you can check the moisture level in your wood using a wood moisture meter. The recommended moisture level suitable for building purposes should be 5-12%.

Types of Moisture in Lumber

Some woods appear wet by merely looking at them; others don’t. You may have lifted some of your wood and discovered that although they don’t appear wet, they feel heavy. In any case, you’re probably wondering why your wood still feels wet or heavy after plenty of exposure to air.

There are two types of moisture in wood:

  • Free water: The free water is infused into the wood pores or penetrates through rainwater, dew, or snow. So, the free water in the wood dries up when exposed to air.
  • Bound water: Bound water traps moisture inside the cell walls of the wood. Drying requires a higher temperature, like a kiln drying method, to remove moisture from the wood. 

Should You Apply a Seal on Your Wet Pressure-Treated Wood?

Pressure-treated woods are prone to cracks and split if left unsealed. This is because, apart from the beauty it adds to your project, the seal serves as a water-repellant and prevents moisture from penetrating your pressure-treated wood.

However, the seal can ruin your work if your pressure-treated wood is wet. Instead of having a smooth surface, you’ll have rough or coarse surfaces.

Therefore, your pressure-treated wood should be allowed to dry completely before applying the sealant. You can wait two to three weeks after installing your deck to ensure it is properly dry.

If the rains fall on your deck after installation, you can wait for two to three days for drying since it is a matter of free water. However, if the wetness is due to bound water, ensure it is completely dried before applying a sealant to avoid cracks on your seal.

So, what’s responsible for the cracks in your seal? The cracks in your seal are caused by drying moisture in your pressure-treated wood. If you apply a sealant on wet wood, the wood shrinks as it dries up and causes your sealant to crack.

Factors That Affect the Speed of Air Drying Your Pressure-Treated Wood

The air drying method for drying pressure-treated wood takes time. However, the speed of drying depends on several factors, such as

  • Weather conditions: Weather can affect the speed of drying. Air-drying is faster when there’s enough sunshine. Sunshine is scarce or almost unavailable during the rainy season or winter. Although other methods are feasible, they’re not as effective as the sunlight.
  • Storage space: Having little storage space to stock your pressure-treated wood is another factor that can impede the drying process. You need an expansive storage space with enough air for effective drying.
  • Location: The location for storing your wood also affects the drying process. Storing your pressure-treated wood where air can not easily reach can also affect proper drying.

Types of Preservatives Used for Pressure-Treated Woods

I mentioned earlier that the major reason your pressure-treated wood feels wet is the water-born treatment used for your pressure-treated wood.

The preservatives are used to determine how wet your pressure-treated wood will be and how much moisture will seep into your pressure-treated wood. There are three major types of preservatives used to protect pressure-treated woods. 

  • Oil-borne preservatives: Oil-borne preservatives have low moisture content. They don’t dissolve readily in water. Petroleum is usually introduced to get the oil-borne preservative to dissolve in water.
  • Waterborne preservatives: They have a lot of moisture. Waterborne preservatives are available in liquid, solid melt, and granular forms. They are best used on the wood used for fences because of their consistent exposure to moisture.
  • Fumigants: These are pesticides that help in the control of internal decay or in eliminating insects that are already existing in woods. Fumigants have no water resistance, so using sealant on pores will be necessary to keep them moist free.

How Long Does a Pressure-Treated Wood Last?

Pressure-treated woods can last a long time, although this varies based on climate, usage, and maintenance. On average, pressure-treated woods can last 10–40 years.

Pressure-treated wood installed outdoors will last longer than those used for indoor purposes. Sunlight and sufficient air will keep them dry and useful for much longer. However, water-protective sealants will help prevent moisture penetration for wood installed in environments with less sunlight exposure and more humidity.

Advantages and Disadvantages of Using Pressure-Treated Wood

Pressure-treated woods come with advantages and disadvantages. Let’s discuss them.

Benefits of Using Pressure-Treated Wood

Using pressure-treated wood offers many advantages

  • Moisture resistance: Using your pressure-treated woods helps to prevent undue moisture content in your deck. Moisture can attract different microorganisms and lead to mold formation. Having it on your decks will cause your wood to decompose and pose certain health risks.
  • Insect resistance: The chemicals used on your pressure-treated wood are pesticides, which keep all kinds of insects off your wood. 
  • Cost: Pressure-treated woods are very expensive compared to other types of wood, but they’re worth it in the long run.
  • Durability: Pressure-treated woods are more durable than other types of wood. And if you dry them properly before using them, you can even enjoy a more extended use for a longer period. Using preservatives is also helpful. We’ll discuss more on this later.

Disadvantages of Pressure-Treated Woods

Pressure-treated woods also come with some disadvantages.

  • Health risks: The toxic chemicals used in processing pressure-treated pose several health risks. Some of these substances escape into the air when these wood are cut or trimmed; prolonged inhalation of these substances can trigger respiratory problems.
  • Shrinking and warping: Some wood can shrink and become warped during the drying process. This would affect the aesthetic appearance of your deck. However, you can use your shrink or warp wood for bracing and blocking your deck to reduce large waste of warped and shrunken wood. You can also straighten the warped pressure-treated wood depending on the situation. [Is Straightening Warped Pressure Treated Wood Possible?]
  • Environmental hazards: The process of manufacturing pressure-treated wood is not eco-friendly. Also, rainfall washes some harmful chemicals in pressure-treated wood into the environment.
  • Cost: Pressure-treated woods are more expensive than regular woods. The cost of using them for a project may exceed many budgets.

Final Thoughts

Your pressure-treated wood feels wet due to waterborne chemicals in the wood pores. A wood moisture meter will reveal the level of moisture in the wood. To remove moisture, you can use kiln or air drying methods. Kiln-drying is more expensive but faster and more effective than air-drying.

Ensure you dry your wood properly before use. This is so because wet pressure-treated wood shrinks while drying, and this can cause cracks if you cover your wood surface with a sealant.

1 thought on “Why Does Your Pressure-Treated Wood Feel Wet?”

  1. I bought some 5/4 x6 lumber at Lowes. It was very wet. (It wasn’t any better at Home Depot but at least they explained to me that it was wet from the pressure treatment process.) After 3 months drying in my garage, it was still damp. Some pieces had warped. Other pieces had fissures that were not present at purchase. Milling the stuff was difficult. I was cutting out pieces on the bandsaw for an Adirondack chair. The center of the board was wet, the edges not so much. The blade had trouble until it got into the dry area at which point it suddenly started cutting very easy and it got my pinky finger. Cutting wet wood is hazardous.


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