Kiln dried firewood has been heat treated in a firewood kiln to reduce moisture content and kill insects, larvae and fungi.
Why is this important?
Invasive insects or diseases can spread when contaminated firewood is moved, potentially infesting a healthy forest.
Seasoned firewood that has been cut, stacked and allowed to dry naturally is not a proven way to eliminate these diseases or invasive insects.
In fact, studies have shown that invasive insects can survive in processed firewood for over two years and still emerge to infest a local forest.
Firewood that has been kiln dried to a core temperature of 160 degrees fahrenheit for at least 75 minutes is an acceptable way to meet the heat treatment standards.
The heat treated firewood will be free from insects and have a low moisture content that allows hot burning fires that are easy to light.
Kiln dried firewood can be used as a primary or secondary source of fuel in any kind of setting, including an open fireplace or fire pit, a campfire, or wood burning stove.
You can typically find this kind of firewood in two forms - as kindling, or as logs.
Kindling is an excellent type of wood to use when you’re first trying to start a fire.
It has a low moisture content so that it catches fire and burns quickly, helping you to get your fire going with minimal hassle.
Logs, on the other hand, can be used when building a fire to help the whole thing catch faster.
You won’t have to worry quite as much about the fire going out.
The firewood is placed in a firewood kiln where high temperatures kill any living insects, larvae or fungi.
To reach a core temperature of 160 degrees fahrenheit in the wood, the internal temperature of the kiln is typically around 180 to 200 degrees.
A standard kiln used to dry lumber is not an acceptable way to treat firewood.
Lumber is dried at a much lower temperature than firewood to prevent distortion in the wood.
These lower temperatures are not enough to reach a sufficient core temperature in the firewood.
The cost of a firewood kiln can be very expensive.
Some models can cost nearly $50,000.
Due to the high initial investment, many people who sell firewood choose not to pursue this option.
Firewood can be kiln dried at any time of the year and you can eliminate months of waiting for your wood to naturally season.
Although the initial startup cost is high, the firewood can be sold at a higher price and shipped to potential customers.
It's important to obtain the proper certifications and abide by all state and federal laws before you ship any firewood or have any firewood shipped to you.
Kiln dried firewood generally contains far less moisture than wood that has been regularly seasoned, so there’s a reduced likelihood that you’ll be buying wood that’s too damp to burn well.
Though it’s more expensive, it will likely be cheaper in the long run because you won’t be using as much wood to get the same heat output.
It also produces less smoke when it is burned.
It can burn much cleaner without as much creosote production, meaning you won’t have to have your flue or chimney cleaned as often.
Because the kiln drying process is more efficient, it will take a fraction of the time to get dried wood.
Seasoning firewood in the traditional sense can take years.
Plus, the process of kiln drying gets rid of any insects so that you can store the firewood inside your house without worrying about pests getting inside.
It also removes most diseases.
If you’re wondering whether the firewood you have purchased is kiln dried, there are a few ways to tell.
For one, if it comes in a bag, it will be labeled as such.
You can check the moisture content - generally, anything less than 10% is a good sign that the wood has been dried in a kiln.
The wood might also look weathered, even compared to seasoned logs that have been sitting outside.
Your firewood will likely be a dark brown in color, with bark that peels away or ends that are splitting.
Kiln dried wood is also quite lightweight.
In general, yes.
Kiln dried firewood can burn much longer than regularly seasoned firewood.
Kiln dried firewood has a moisture content of less than 20%.
Many people who sell kiln dried firewood use moisture meters to check levels.
While it’s always less than 20%, some kiln dried firewood can have 6% or less of moisture - much drier than you might expect, that’s for sure!
Of course, there are a few disadvantages of kiln dried firewood to note, too, though these are minimal.
For one, kiln drying can cause moisture levels to dip too low for efficient burning.
Since it burns so quickly, you may have to add wood more often.
It can also be more expensive than any other kind of firewood.
As state and federal guidelines continue to become more restrictive about moving firewood, many people are considering a firewood kiln to take their firewood business to the next level.
For those who purchase kiln dried firewood, you can expect to pay a higher price but you will be receiving premium firewood.